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Sample records for acid receptor beta

  1. TRANSCRIPTIONAL REGULATION OF RETINOIC ACID RECEPTOR-BETA IN RETINOIC ACID-SENSITIVE AND ACID-RESISTANT P19-EMBRYOCARCINOMA CELLS

    NARCIS (Netherlands)

    KRUYT, FAE; VANDENBRINK, CE; DEFIZE, LHK; DONATH, MJ; KASTNER, P; KRUIJER, W; CHAMBON, P; VANDERSAAG, PT; Kruyt, Frank

    1991-01-01

    As in other embryocarcinoma (EC) cell lines retinoic acid (RA) rapidly induces expression of the nuclear retinoic acid receptor (RAR) beta in murine P19 EC cells, while RAR-alpha is expressed constitutively. In the RA-resistant P19 EC-derived RAC65 cells, however, there is no such induction and an a

  2. Activation of transmembrane bile acid receptor TGR5 stimulates insulin secretion in pancreatic {beta} cells

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Divya P.; Rajagopal, Senthilkumar; Mahavadi, Sunila [Department of Physiology and Biophysics, Virginia Commonwealth University School of Medicine, Richmond, VA (United States); Mirshahi, Faridoddin [Division of Gastroenterology, Hepatology and Nutrition, Department of Internal Medicine, Virginia Commonwealth University School of Medicine, Richmond, VA (United States); Grider, John R. [Department of Physiology and Biophysics, Virginia Commonwealth University School of Medicine, Richmond, VA (United States); Murthy, Karnam S., E-mail: skarnam@vcu.edu [Department of Physiology and Biophysics, Virginia Commonwealth University School of Medicine, Richmond, VA (United States); Sanyal, Arun J., E-mail: asanyal@mcvh-vcu.edu [Division of Gastroenterology, Hepatology and Nutrition, Department of Internal Medicine, Virginia Commonwealth University School of Medicine, Richmond, VA (United States)

    2012-10-26

    Highlights: Black-Right-Pointing-Pointer G protein coupled receptor TGR5 is expressed in mouse and human islets. Black-Right-Pointing-Pointer TGR5 is coupled to activation of Gs and Ca{sup 2+} release via cAMP/Epac/PLC-{epsilon} pathway. Black-Right-Pointing-Pointer Activation of TGR5 by bile salts and selective ligands causes insulin secretion. Black-Right-Pointing-Pointer TGR5 could be a potential therapeutic target to treat diabetes. -- Abstract: Bile acids act as signaling molecules and stimulate the G protein coupled receptor, TGR5, in addition to nuclear farnesoid X receptor to regulate lipid, glucose and energy metabolism. Bile acid induced activation of TGR5 in the enteroendocrine cells promotes glucagon like peptide-1 (GLP-1) release, which has insulinotropic effect in the pancreatic {beta} cells. In the present study, we have identified the expression of TGR5 in pancreatic {beta} cell line MIN6 and also in mouse and human pancreatic islets. TGR5 selective ligands, oleanolic acid (OA) and INT-777 selectively activated G{alpha}{sub s} and caused an increase in intracellular cAMP and Ca{sup 2+}. OA and INT-777 also increased phosphoinositide (PI) hydrolysis and the increase was blocked by NF449 (a selective G{alpha}{sub s} inhibitor) or (U73122) (PI hydrolysis inhibitor). OA, INT-777 and lithocholic acid increased insulin release in MIN6 and human islets and the increase was inhibited by treatment with NF449, (U73122) or BAPTA-AM (chelator of calcium), but not with myristoylated PKI (PKA inhibitor), suggesting that the release is dependent on G{sub s}/cAMP/Ca{sup 2+} pathway. 8-pCPT-2 Prime -O-Me-cAMP, a cAMP analog, which activates Epac, but not PKA also stimulated PI hydrolysis. In conclusion, our study demonstrates that the TGR5 expressed in the pancreatic {beta} cells regulates insulin secretion and highlights the importance of ongoing therapeutic strategies targeting TGR5 in the control of glucose homeostasis.

  3. Retinoic acid receptor beta2 promotes functional regeneration of sensory axons in the spinal cord.

    Science.gov (United States)

    Wong, Liang-Fong; Yip, Ping K; Battaglia, Anna; Grist, John; Corcoran, Jonathan; Maden, Malcolm; Azzouz, Mimoun; Kingsman, Susan M; Kingsman, Alan J; Mazarakis, Nicholas D; McMahon, Stephen B

    2006-02-01

    The embryonic CNS readily undergoes regeneration, unlike the adult CNS, which has limited axonal repair after injury. Here we tested the hypothesis that retinoic acid receptor beta2 (RARbeta2), critical in development for neuronal growth, may enable adult neurons to grow in an inhibitory environment. Overexpression of RARbeta2 in adult rat dorsal root ganglion cultures increased intracellular levels of cyclic AMP and stimulated neurite outgrowth. Stable RARbeta2 expression in DRG neurons in vitro and in vivo enabled their axons to regenerate across the inhibitory dorsal root entry zone and project into the gray matter of the spinal cord. The regenerated neurons enhanced second-order neuronal activity in the spinal cord, and RARbeta2-treated rats showed highly significant improvement in sensorimotor tasks. These findings show that RARbeta2 induces axonal regeneration programs within injured neurons and may thus offer new therapeutic opportunities for CNS regeneration. PMID:16388307

  4. Recessive and dominant mutations in retinoic acid receptor beta in cases with microphthalmia and diaphragmatic hernia.

    Science.gov (United States)

    Srour, Myriam; Chitayat, David; Caron, Véronique; Chassaing, Nicolas; Bitoun, Pierre; Patry, Lysanne; Cordier, Marie-Pierre; Capo-Chichi, José-Mario; Francannet, Christine; Calvas, Patrick; Ragge, Nicola; Dobrzeniecka, Sylvia; Hamdan, Fadi F; Rouleau, Guy A; Tremblay, André; Michaud, Jacques L

    2013-10-01

    Anophthalmia and/or microphthalmia, pulmonary hypoplasia, diaphragmatic hernia, and cardiac defects are the main features of PDAC syndrome. Recessive mutations in STRA6, encoding a membrane receptor for the retinol-binding protein, have been identified in some cases with PDAC syndrome, although many cases have remained unexplained. Using whole-exome sequencing, we found that two PDAC-syndrome-affected siblings, but not their unaffected sibling, were compound heterozygous for nonsense (c.355C>T [p.Arg119(∗)]) and frameshift (c.1201_1202insCT [p.Ile403Serfs(∗)15]) mutations in retinoic acid receptor beta (RARB). Transfection studies showed that p.Arg119(∗) and p.Ile403Serfs(∗)15 altered RARB had no transcriptional activity in response to ligands, confirming that the mutations induced a loss of function. We then sequenced RARB in 15 subjects with anophthalmia and/or microphthalmia and at least one other feature of PDAC syndrome. Surprisingly, three unrelated subjects with microphthalmia and diaphragmatic hernia showed de novo missense mutations affecting the same codon; two of the subjects had the c.1159C>T (Arg387Cys) mutation, whereas the other one carried the c.1159C>A (p.Arg387Ser) mutation. We found that compared to the wild-type receptor, p.Arg387Ser and p.Arg387Cys altered RARB induced a 2- to 3-fold increase in transcriptional activity in response to retinoic acid ligands, suggesting a gain-of-function mechanism. Our study thus suggests that both recessive and dominant mutations in RARB cause anophthalmia and/or microphthalmia and diaphragmatic hernia, providing further evidence of the crucial role of the retinoic acid pathway during eye development and organogenesis.

  5. Retinoic acid receptor beta2 and neurite outgrowth in the adult mouse spinal cord in vitro.

    Science.gov (United States)

    Corcoran, Jonathan; So, Po-Lin; Barber, Robert D; Vincent, Karen J; Mazarakis, Nicholas D; Mitrophanous, Kyriacos A; Kingsman, Susan M; Maden, Malcolm

    2002-10-01

    Retinoic acid, acting through the nuclear retinoic acid receptor beta2 (RARbeta2), stimulates neurite outgrowth from peripheral nervous system tissue that has the capacity to regenerate neurites, namely, embryonic and adult dorsal root ganglia. Similarly, in central nervous system tissue that can regenerate, namely, embryonic mouse spinal cord, retinoic acid also stimulates neurite outgrowth and RARbeta2 is upregulated. By contrast, in the adult mouse spinal cord, which cannot regenerate, no such upregulation of RARbeta2 by retinoic acid is observed and no neurites are extended in vitro. To test our hypothesis that the upregulation of RARbeta2 is crucial to neurite regeneration, we have transduced adult mouse or rat spinal cord in vitro with a minimal equine infectious anaemia virus vector expressing RARbeta2. After transduction, prolific neurite outgrowth occurs. Outgrowth does not occur when the cord is transduced with a different isoform of RARbeta nor does it occur following treatment with nerve growth factor. These data demonstrate that RARbeta2 is involved in neurite outgrowth, at least in vitro, and that this gene may in the future be of some therapeutic use. PMID:12235288

  6. Functional modulation of cerebral gamma-aminobutyric acidA receptor/benzodiazepine receptor/chloride ion channel complex with ethyl beta-carboline-3-carboxylate: Presence of independent binding site for ethyl beta-carboline-3-carboxylate

    Energy Technology Data Exchange (ETDEWEB)

    Taguchi, J.; Kuriyama, K. (Kyoto Prefectural Univ. of Medicine (Japan))

    1990-05-01

    Effect of ethyl beta-carboline-3-carboxylate (beta-CCE) on the function of gamma-aminobutyric acid (GABA)A receptor/benzodiazepine receptor/chloride ion channel complex was studied. Beta-CCE noncompetitively and competitively inhibited (3H)flunitrazepam binding to benzodiazepine receptor, but not (3H)muscimol binding to GABAA receptor as well as t-(3H)butylbicycloorthobenzoate (( 3H) TBOB) binding to chloride ion channel, in particulate fraction of the mouse brain. Ro15-1788 also inhibited competitively (3H) flunitrazepam binding. On the other hand, the binding of beta-(3H)CCE was inhibited noncompetitively and competitively by clonazepam and competitively by Ro15-1788. In agreement with these results, benzodiazepines-stimulated (3H)muscimol binding was antagonized by beta-CCE and Ro15-1788. Gel column chromatography for the solubilized fraction from cerebral particulate fraction by 0.2% sodium deoxycholate (DOC-Na) in the presence of 1 M KCl indicated that beta-(3H)CCE binding site was eluted in the same fraction (molecular weight, 250,000) as the binding sites for (3H)flunitrazepam, (3H)muscimol and (3H)TBOB. GABA-stimulated 36Cl- influx into membrane vesicles prepared from the bovine cerebral cortex was stimulated and attenuated by flunitrazepam and beta-CCE, respectively. These effects of flunitrazepam and beta-CCE on the GABA-stimulated 36Cl- influx were antagonized by Ro15-1788. The present results suggest that the binding site for beta-CCE, which resides on GABAA receptor/benzodiazepine receptor/chloride ion channel complex, may be different from that for benzodiazepine. Possible roles of beta-CCE binding site in the allosteric inhibitions on benzodiazepine binding site as well as on the functional coupling between chloride ion channel and GABAA receptor are also suggested.

  7. Functional modulation of cerebral gamma-aminobutyric acidA receptor/benzodiazepine receptor/chloride ion channel complex with ethyl beta-carboline-3-carboxylate: Presence of independent binding site for ethyl beta-carboline-3-carboxylate

    International Nuclear Information System (INIS)

    Effect of ethyl beta-carboline-3-carboxylate (beta-CCE) on the function of gamma-aminobutyric acid (GABA)A receptor/benzodiazepine receptor/chloride ion channel complex was studied. Beta-CCE noncompetitively and competitively inhibited [3H]flunitrazepam binding to benzodiazepine receptor, but not [3H]muscimol binding to GABAA receptor as well as t-[3H]butylbicycloorthobenzoate [( 3H] TBOB) binding to chloride ion channel, in particulate fraction of the mouse brain. Ro15-1788 also inhibited competitively [3H] flunitrazepam binding. On the other hand, the binding of beta-[3H]CCE was inhibited noncompetitively and competitively by clonazepam and competitively by Ro15-1788. In agreement with these results, benzodiazepines-stimulated [3H]muscimol binding was antagonized by beta-CCE and Ro15-1788. Gel column chromatography for the solubilized fraction from cerebral particulate fraction by 0.2% sodium deoxycholate (DOC-Na) in the presence of 1 M KCl indicated that beta-[3H]CCE binding site was eluted in the same fraction (molecular weight, 250,000) as the binding sites for [3H]flunitrazepam, [3H]muscimol and [3H]TBOB. GABA-stimulated 36Cl- influx into membrane vesicles prepared from the bovine cerebral cortex was stimulated and attenuated by flunitrazepam and beta-CCE, respectively. These effects of flunitrazepam and beta-CCE on the GABA-stimulated 36Cl- influx were antagonized by Ro15-1788. The present results suggest that the binding site for beta-CCE, which resides on GABAA receptor/benzodiazepine receptor/chloride ion channel complex, may be different from that for benzodiazepine. Possible roles of beta-CCE binding site in the allosteric inhibitions on benzodiazepine binding site as well as on the functional coupling between chloride ion channel and GABAA receptor are also suggested

  8. Identification of three adjacent amino acids of interleukin-2 receptor beta chain which control the affinity and the specificity of the interaction with interleukin-2.

    OpenAIRE

    Imler, J L; Miyajima, A; Zurawski, G

    1992-01-01

    The beta chain of the interleukin-2 (IL-2) receptor (IL-2R beta) and the interleukin-3 (IL-3) binding protein AIC2A are members of the family of cytokine receptors, which also includes the receptors for growth hormone (GHR) and prolactin. A four amino acid sequence of AIC2A has recently been shown to be critical for IL-3 binding. We analyze here the function of the analogous sequence of human IL-2R beta and identify three amino acids, Ser132, His133 and Tyr134, which play a critical role in I...

  9. Arginine of retinoic acid receptor beta which coordinates with the carboxyl group of retinoic acid functions independent of the amino acid residues responsible for retinoic acid receptor subtype ligand specificity.

    Science.gov (United States)

    Zhang, Zeng Ping; Hutcheson, Juliet M; Poynton, Helen C; Gabriel, Jerome L; Soprano, Kenneth J; Soprano, Dianne Robert

    2003-01-15

    The biological actions of retinoic acid (RA) are mediated by retinoic acid receptors (RARalpha, RARbeta, and RARgamma) and retinoid X receptors (RXRalpha, RXRbeta, and RXRgamma). Consistent with the X-ray crystal structures of RARalpha and RARgamma, site-directed mutagenesis studies have demonstrated the importance of a conserved Arg residue (alphaArg(276), betaArg(269), and gammaArg(278)) for coordination with the carboxyl group of RA. However, mutation of Arg(269) to Ala in RARbeta causes only a 3- to 6-fold increase in the K(d) for RA and EC(50) in RA-dependent transcriptional transactivation assays while the homologous mutation in either RARalpha or RARgamma causes a 110-fold and a 45-fold increase in EC(50) value, respectively. To further investigate the nature of this difference, we prepared mutant RARs to determine the effect of conversion of betaR269A to a mutant which mimics either RARalpha ligand selectivity (betaA225S/R269A) or RARgamma ligand selectivity (betaI263M/R269A/V338A). Our results demonstrate that in RARbeta mutants that acquire either RARalpha or RARgamma ligand specificity the Arg(269) position responsible for coordination with the carboxyl group of retinoids continued to function like that of RARbeta. Furthermore, three mutant receptors (betaA225S/R269A, betaA225S/F279, and alphaF286A) were found to have a greater than wild-type affinity for the RARalpha-selective ligand Am580. Finally, a homology-based computer model of the ligand binding domain (LBD) of RARbeta and the X-ray crystal structures of the LBD of both RARalpha and RARgamma are used to describe potential mechanisms responsible for the increased affinity of some mutants for Am580 and for the difference in the effect of mutation of Arg(269) in RARbeta compared to its homologous Arg in RARalpha and RARgamma.

  10. Axial (HNF3beta) and retinoic acid receptors are regulators of the zebrafish sonic hedgehog promoter.

    OpenAIRE

    Chang, B E; Blader, P.; Fischer, N.; Ingham, P W; Strähle, U.

    1997-01-01

    The signalling molecule Sonic hedgehog is involved in a multitude of distinct patterning processes during vertebrate embryogenesis. In the nascent body axis of the zebrafish embryo, sonic hedgehog is co-expressed with axial (HNF3beta in mammals), a transcription regulator of the winged helix family. We show here that misexpression of axial leads to ectopic activation of sonic hedgehog expression in the zebrafish, suggesting that axial is a regulator of sonic hedgehog transcription. The sonic ...

  11. All-trans retinoic acid modulates mitogen-activated protein kinase pathway activation in human scleral fibroblasts through retinoic acid receptor beta

    Science.gov (United States)

    Huo, Lijun; Cui, Dongmei; Yang, Xiao; Gao, Zhenya; Trier, Klaus

    2013-01-01

    Purpose All-trans retinoic acid (ATRA) is known to inhibit the proliferation of human scleral fibroblasts (HSFs) and to modulate the scleral intercellular matrix composition, and may therefore serve as a mediator for controlling eye growth. Cell proliferation is regulated by the mitogen-activated protein kinase (MAPK) pathway. The aim of the current study was to investigate whether changed activation of the MAPK pathway could be involved in the response of HSFs exposed to ATRA. Methods HSFs were cultured in Dulbecco Modified Eagle's Medium/F12 (DMEM/F12) and exposed to 1 μmol/l ATRA for 10 min, 30 min, 1 h, 8 h, or 24 h. The activation of extracellular signal-regulated kinase (ERK 1/2), p38, and c-Jun N-terminal kinase (JNK) in HSFs was assessed with western blot analysis and immunocytofluorescence. Results After exposure to ATRA for 24 h, the HSFs appeared shrunken and thinner than the control cells. The intercellular spaces were wider, and the HSFs appeared less numerous than in the control culture. Western blot showed decreased activation of ERK 1/2 in the HSFs from 30 min (p=0.01) to 24 h (p<0.01) after the start of exposure to ATRA, and increased activation of the JNK protein from 10 to 30 min (p<0.01) after the start of exposure to ATRA. Indirect immunofluorescence confirmed changes in activation of ERK 1/2 and JNK in HSFs exposed to ATRA. No change in activation of p38 in HSFs was observed after exposure to ATRA. Pretreatment of the HSFs with LE135, an antagonist of retinoic acid receptor beta (RARβ), abolished the ATRA-induced changes inactivation of ERK 1/2 and JNK. Conclusions ATRA inhibits HSF proliferation by a mechanism associated with modulation of ERK 1/2 and JNK activation and depends on stimulation of retinoic acid receptor beta. PMID:23946634

  12. Stoichiometry of expressed alpha(4)beta(2)delta gamma-aminobutyric acid type A receptors depends on the ratio of subunit cDNA transfected.

    Science.gov (United States)

    Wagoner, Kelly R; Czajkowski, Cynthia

    2010-05-01

    The gamma-aminobutyric acid type A receptor (GABA(A)R) is the target of many depressants, including benzodiazepines, anesthetics, and alcohol. Although the highly prevalent alphabetagamma GABA(A)R subtype mediates the majority of fast synaptic inhibition in the brain, receptors containing delta subunits also play a key role, mediating tonic inhibition and the actions of endogenous neurosteroids and alcohol. However, the fundamental properties of delta-containing GABA(A)Rs, such as subunit stoichiometry, are not well established. To determine subunit stoichiometry of expressed delta-containing GABA(A)Rs, we inserted the alpha-bungarotoxin binding site tag in the alpha(4), beta(2), and delta subunit N termini. An enhanced green fluorescent protein tag was also inserted into the beta(2) subunit to shift its molecular weight, allowing us to separate subunits using SDS-PAGE. Tagged alpha(4)beta(2)delta GABA(A)Rs were expressed in HEK293T cells using various ratios of subunit cDNA, and receptor subunit stoichiometry was determined by quantitating fluorescent alpha-bungarotoxin bound to each subunit on Western blots of surface immunopurified tagged GABA(A)Rs. The results demonstrate that the subunit stoichiometry of alpha(4)beta(2)delta GABA(A)Rs is regulated by the ratio of subunit cDNAs transfected. Increasing the ratio of delta subunit cDNA transfected increased delta subunit incorporation into surface receptors with a concomitant decrease in beta(2) subunit incorporation. Because receptor subunit stoichiometry can directly influence GABA(A)R pharmacological and functional properties, considering how the transfection protocols used affect subunit stoichiometry is essential when studying heterologously expressed alpha(4)beta(2)delta GABA(A)Rs. Successful bungarotoxin binding site tagging of GABA(A)R subunits is a novel tool with which to accurately quantitate subunit stoichiometry and will be useful for monitoring GABA(A)R trafficking in live cells.

  13. Triiodothyronine receptor beta-2 messenger ribonucleic acid expression by somatotropes and thyrotropes: effect of propylthiouracil-induced hypothyroidism in rats.

    Science.gov (United States)

    Childs, G V; Taub, K; Jones, K E; Chin, W W

    1991-11-01

    mRNA for a thyroid hormone receptor isoform that is unique to the pituitary gland (TR beta-2) is down-regulated by T3. Increases in the expression of this mRNA are seen in rats rendered hypothyroid by treatment with propylthiouracil (PTU). This study used dual labeling to determine which pituitary cells expressed TR beta-2 mRNA in normal and PTU-treated rats. In situ hybridization protocols localized the mRNA (with biotinylated complementary oligonucleotide probes detected by avidin-biotin-peroxidase), and immunoperoxidase protocols identified the pituitary hormone proteins. In dispersed pituitary cells, 20 +/- 2% (average +/- SD) of cells from normal rats and 30 +/- 3% of cells from PTU-treated rats were labeled for TR beta-2 mRNA. PTU caused increases in the area of the labeled cells (from 114 +/- 11 to 225 +/- 7 microns 2), the area of the label per cell (from 27 +/- 3 to 71 +/- 11 microns 2), and label density. PTU produced increases in the percentage of TSH cells from 8 +/- 1% to 19 +/- 2%, decreases in the percentage of GH cells from 27 +/- 3% to 11 +/- 2%, and no change in other cell types. After dual labeling, 73% of cells that expressed TR beta-2 mRNA stored either TSH (35 +/- 8) or GH (38 +/- 6). Less than 10% stored other hormones. When each cell type was analyzed, 56 +/- 3% of TSH cells and 43 +/- 4% of GH cells expressed TR beta-2 mRNA. When these percentages were multiplied by the percentages of each cell type in the overall population, TSH and GH cells with TR beta-2 mRNA represented 6.8 +/- 1% and 11.6 +/- 1% of the pituitary cells, respectively. Less than 1% of all pituitary cells expressed TR beta-2 and ACTH (0.9 +/- 0.06), LH (0.8 +/- 0.1), FSH (0.8 +/- 0.1), and PRL (0.9 +/- 0.04). PTU treatment increased the percentage of TSH cells with TR beta-2 mRNA to 72 +/- 4% and decreased the percentage of GH cells with TR beta-2 mRNA to 30 +/- 3%. However, some enlarged putative TSH cells could not be identified by immunolabel because the storage levels

  14. Ryanodine receptor type I and nicotinic acid adenine dinucleotide phosphate receptors mediate Ca2+ release from insulin-containing vesicles in living pancreatic beta-cells (MIN6).

    Science.gov (United States)

    Mitchell, Kathryn J; Lai, F Anthony; Rutter, Guy A

    2003-03-28

    We have demonstrated recently (Mitchell, K. J., Pinton, P., Varadi, A., Tacchetti, C., Ainscow, E. K., Pozzan, T., Rizzuto, R., and Rutter, G. A. (2001) J. Cell Biol. 155, 41-51) that ryanodine receptors (RyR) are present on insulin-containing secretory vesicles. Here we show that pancreatic islets and derived beta-cell lines express type I and II, but not type III, RyRs. Purified by subcellular fractionation and membrane immuno-isolation, dense core secretory vesicles were found to possess a similar level of type I RyR immunoreactivity as Golgi/endoplasmic reticulum (ER) membranes but substantially less RyR II than the latter. Monitored in cells expressing appropriately targeted aequorins, dantrolene, an inhibitor of RyR I channels, elevated free Ca(2+) concentrations in the secretory vesicle compartment from 40.1 +/- 6.7 to 90.4 +/- 14.8 microm (n = 4, p < 0.01), while having no effect on ER Ca(2+) concentrations. Furthermore, nicotinic acid adenine dinucleotide phosphate (NAADP), a novel Ca(2+)-mobilizing agent, decreased dense core secretory vesicle but not ER free Ca(2+) concentrations in permeabilized MIN6 beta-cells, and flash photolysis of caged NAADP released Ca(2+) from a thapsigargin-insensitive Ca(2+) store in single MIN6 cells. Because dantrolene strongly inhibited glucose-stimulated insulin secretion (from 3.07 +/- 0.51-fold stimulation to no significant glucose effect; n = 3, p < 0.01), we conclude that RyR I-mediated Ca(2+)-induced Ca(2+) release from secretory vesicles, possibly potentiated by NAADP, is essential for the activation of insulin secretion.

  15. Prognostic Value of Promoter Hypermethylation of Retinoic Acid Receptor Beta (RARB) and CDKN2 (p16/MTS1) in Prostate Cancer

    Institute of Scientific and Technical Information of China (English)

    Ameri A; Alidoosti A; Hosseini Y; Parvin M; Emranpour MH; Taslimi F; Salehi E; Fadavi P

    2011-01-01

    Objective:The molecular mechanism of prostate cancer is poorly understood.The aim of the study was to investigate the prevalence and prognostic value of promoter hypermethylation of retinoic acid receptor beta (RARB) and p16 among benign prostatic hyperplasia (BPH) and prostate cancer patients.Methods:In this case-control study,63 patients were included in three groups; 21 with BPH as the control group,21 with prostate cancer and good prognostic factors (based on prostate-specific antigen,Gleason score and stage) as good prognosis group,and 21 with prostate cancer and poor prognostic features as poor prognosis group.The prostate biopsy specimen of each individual was examined for hypermethylation of RARB and p16 promoters by methylation specific PCR (MSPCR).Results:Seven (33.3%) patients with good prognosis and 15 (71.4%) patients with poor prognosis were positive for RARB methylation,which were significantly higher than controls (P <0.0001).p16 promoter methylation was shown in 19.0% and 47.6% patients with good and poor prognosis,respectively.The RARB and p16 promoter methylation in the poor prognosis group was significantly higher than that in the good prognosis group (P -0.02 for RARB and P<0.0001 for p16).Conclusion:Hypermethylation of RARB and p16 promoters may predict prognosis in prostate cancer.

  16. The Expression of Bone Morphogenetic Protein 2 and Matrix Metalloproteinase 2 through Retinoic Acid Receptor Beta Induced by All-Trans Retinoic Acid in Cultured ARPE-19 Cells.

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    Zhenya Gao

    Full Text Available All-trans retinoic acid (ATRA plays an important role in ocular development. Previous studies found that retinoic acid could influence the metabolism of scleral remodeling by promoting retinal pigment epithelium (RPE cells to secrete secondary signaling factors. The purpose of this study was to investigate whether retinoic acid affected secretion of bone morphogenetic protein 2 (BMP-2 and matrix metalloproteinase 2 (MMP-2 and to explore the signaling pathway of retinoic acid in cultured acute retinal pigment epithelial 19 (ARPE-19 cells.The effects of ATRA (concentrations from 10-9 to 10-5 mol/l on the expression of retinoic acid receptors (RARs in ARPE-19 cells were examined at the mRNA and protein levels using reverse transcription-polymerase chain reaction (RT-PCR and western blot assay, respectively. The effects of treating ARPE-19 cells with ATRA concentrations ranging from 10-9 to 10-5 mol/l for 24 h and 48 h or with 10-6mol/l ATRA at different times ranging from 6h to 72h were assessed using real-time quantitative PCR (qPCR and enzyme-linked immunosorbent assay (ELISA. The contribution of RARβ-induced activation of ARPE-19 cells was confirmed using LE135, an antagonist of RARβ.RARβ mRNA levels significantly increased in the ARPE-19 cells treated with ATRA for 24h and 48h. These increases in RARβ mRNA levels were dose dependent (at concentrations of 10-9 to 10-5 mol/l with a maximum effect observed at 10-6 mol/l. There were no significant changes in the mRNA levels of RARα and RARγ. Western blot assay revealed that RARβ protein levels were increased significantly in a time-dependent manner in ARPE-19 cells treated with 10-6 mol/l ATRA from 12 h to 72 h, with a marked increase observed at 24 h and 48 h. The upregulation of RARβ and the ATRA-induced secretion in ARPE-19 cells could be inhibited by the RARβ antagonist LE135.ATRA induced upregulation of RARβ in ARPE-19 cells and stimulated these cells to secrete BMP-2 and MMP-2.

  17. The Expression of Bone Morphogenetic Protein 2 and Matrix Metalloproteinase 2 through Retinoic Acid Receptor Beta Induced by All-Trans Retinoic Acid in Cultured ARPE-19 Cells

    Science.gov (United States)

    Gao, Zhenya; Huo, Lijun; Cui, Dongmei; Yang, Xiao; Zeng, Junwen

    2016-01-01

    Purpose All-trans retinoic acid (ATRA) plays an important role in ocular development. Previous studies found that retinoic acid could influence the metabolism of scleral remodeling by promoting retinal pigment epithelium (RPE) cells to secrete secondary signaling factors. The purpose of this study was to investigate whether retinoic acid affected secretion of bone morphogenetic protein 2 (BMP-2) and matrix metalloproteinase 2 (MMP-2) and to explore the signaling pathway of retinoic acid in cultured acute retinal pigment epithelial 19 (ARPE-19) cells. Methods The effects of ATRA (concentrations from 10−9 to 10−5 mol/l) on the expression of retinoic acid receptors (RARs) in ARPE-19 cells were examined at the mRNA and protein levels using reverse transcription-polymerase chain reaction (RT-PCR) and western blot assay, respectively. The effects of treating ARPE-19 cells with ATRA concentrations ranging from 10−9 to 10−5 mol/l for 24 h and 48 h or with 10-6mol/l ATRA at different times ranging from 6h to 72h were assessed using real-time quantitative PCR (qPCR) and enzyme-linked immunosorbent assay (ELISA). The contribution of RARβ-induced activation of ARPE-19 cells was confirmed using LE135, an antagonist of RARβ. Results RARβ mRNA levels significantly increased in the ARPE-19 cells treated with ATRA for 24h and 48h. These increases in RARβ mRNA levels were dose dependent (at concentrations of 10−9 to 10−5 mol/l) with a maximum effect observed at 10−6 mol/l. There were no significant changes in the mRNA levels of RARα and RARγ. Western blot assay revealed that RARβ protein levels were increased significantly in a time-dependent manner in ARPE-19 cells treated with 10−6 mol/l ATRA from 12 h to 72 h, with a marked increase observed at 24 h and 48 h. The upregulation of RARβ and the ATRA-induced secretion in ARPE-19 cells could be inhibited by the RARβ antagonist LE135. Conclusion ATRA induced upregulation of RARβ in ARPE-19 cells and stimulated

  18. The Expression of Bone Morphogenetic Protein 2 and Matrix Metalloproteinase 2 through Retinoic Acid Receptor Beta Induced by All-Trans Retinoic Acid in Cultured ARPE-19 Cells

    OpenAIRE

    Zhenya Gao; Lijun Huo; Dongmei Cui; Xiao Yang; Junwen Zeng

    2016-01-01

    Purpose All-trans retinoic acid (ATRA) plays an important role in ocular development. Previous studies found that retinoic acid could influence the metabolism of scleral remodeling by promoting retinal pigment epithelium (RPE) cells to secrete secondary signaling factors. The purpose of this study was to investigate whether retinoic acid affected secretion of bone morphogenetic protein 2 (BMP-2) and matrix metalloproteinase 2 (MMP-2) and to explore the signaling pathway of retinoic acid in cu...

  19. Ursolic acid, an antagonist for transforming growth factor (TGF)-beta1.

    Science.gov (United States)

    Murakami, Shigeru; Takashima, Hajime; Sato-Watanabe, Mariko; Chonan, Sumi; Yamamoto, Koji; Saitoh, Masako; Saito, Shiuji; Yoshimura, Hiromitsu; Sugawara, Koko; Yang, Junshan; Gao, Nannan; Zhang, Xinggao

    2004-05-21

    Transforming growth factor-beta (TGF-beta), a multifunctional cytokine which is involved in extracellular matrix modulation, has a major role in the pathogenesis and progression of fibrotic diseases. We now report the effects of ursolic acid on TGF-beta1 receptor binding and TGF-beta1-induced cellular functions in vitro. Ursolic acid inhibited [(125)I]-TGF-beta1 receptor binding to Balb/c 3T3 mouse fibroblasts with an IC(50) value of 6.9+/-0.8 microM. Ursolic acid dose-dependently recovered reduced proliferation of Minc Mv1Lu cells in the presence of 5 nM of TGF-beta1 and attenuated TGF-beta1-induced collagen synthesis and production in human fibroblasts. Molecular dynamics simulations suggest that ursolic acid may interact with the hydrophobic region of the dimeric interface and thereby inhibit the binding of TGF-beta1 to its receptor. All these findings taken together show that ursolic acid functions as an antagonist for TGF-beta1. This is the first report to show that a small molecule can inhibit TGF-beta1 receptor binding and influence functions of TGF-beta1.

  20. Evolution of T cell receptor genes. Extensive diversity of V beta families in the Mexican axolotl.

    Science.gov (United States)

    Fellah, J S; Kerfourn, F; Charlemagne, J

    1994-11-15

    We have cloned 36 different rearranged variable regions (V beta) genes encoding the beta-chain of the T cell receptor in an amphibian species, Ambystoma mexicanum (the Mexican axolotl). Eleven different V beta segments were identified, which can be classified into 9 families on the basis of a minimum of 75% nucleotide identity. All the cloned V beta segments have the canonical features of known mammalian and avian V beta, including conserved residues Cys23, Trp34, Arg69, Tyr90, and Cys92. There seems to be a greater genetic distance between the axolotl V beta families than between the different V beta families of any mammalian species examined to date: most of the axolotl V beta s have fewer than 35% identical nucleotides and the less related families (V beta 4 and V beta 8) have no more than 23.2% identity (13.5% at the amino acid level). Despite their great mutual divergence, several axolotl V beta are sequence-related to some mammalian V beta genes, like the human V beta 13 and V beta 20 segments and their murine V beta 8 and V beta 14 homologues. However, the axolotl V beta 8 and V beta 9 families are not significantly related to any other V beta sequence at the nucleotide level and show limited amino acid similarity to mammalian V alpha, V kappa III, or VH sequences. The detection of nine V beta families among 35 randomly cloned V beta segments suggests that the V beta gene repertoire in the axolotl is probably larger than presently estimated. PMID:7963525

  1. Conserved structure of amphibian T-cell antigen receptor beta chain.

    Science.gov (United States)

    Fellah, J S; Kerfourn, F; Guillet, F; Charlemagne, J

    1993-07-15

    All jawed vertebrates possess well-differentiated thymuses and elicit T-cell-like cell-mediated responses; however, no surface T-cell receptor (TCR) molecules or TCR genes have been identified in ectothermic vertebrate species. Here we describe cDNA clones from an amphibian species, Ambystoma mexicanum (the Mexican axolotl), that have sequences highly homologous to the avian and mammalian TCR beta chains. The cloned amphibian beta chain variable region (V beta) shares most of the structural characteristics with the more evolved vertebrate V beta and presents approximately 56% amino acid identities with the murine V beta 14 and human V beta 18 families. The two different cloned axolotl beta chain joining regions (J beta) were found to have conserved all the invariant mammalian J beta residues, and in addition, the presence of a conserved glycine at the V beta-J beta junction suggests the existence of diversity elements. The extracellular domains of the two axolotl beta chain constant region isotypes C beta 1 and C beta 2 show an impressively high degree of identity, thus suggesting that a very efficient mechanism of gene correction has been in operation to preserve this structure at least from the early tetrapod evolution. The transmembrane axolotl C beta domains have been less well conserved when compared to the mammalian C beta but they do maintain the lysine residue that is thought to be involved in the charged interaction between the TCR alpha beta heterodimer and the CD3 complex. PMID:8341702

  2. Role of human GABA(A) receptor beta3 subunit in insecticide toxicity.

    Science.gov (United States)

    Ratra, G S; Kamita, S G; Casida, J E

    2001-05-01

    The gamma-aminobutyric acid type A (GABA(A)) receptor is the target for the major insecticides alpha-endosulfan, lindane, and fipronil and for many analogs. Their action as chloride channel blockers is directly measured by binding studies with [(3)H]ethynylbicycloorthobenzoate ([(3)H]EBOB). This study tests the hypothesis that GABA(A) receptor subunit composition determines the sensitivity and selectivity of insecticide toxicity. Human receptor subtypes were expressed individually (alpha1, alpha6, beta1, beta3, and gamma2) and in combination in insect Sf9 cells. Binding parameters were similar for [(3)H]EBOB in the beta3 homooligomer, alpha1beta3gamma2 heterooligomer, and native brain membranes, but toxicological profiles were very different. Surprisingly, alpha-endosulfan, lindane, and fipronil were all remarkably potent on the recombinant beta3 homooligomeric receptor (IC50 values of 0.5-2.4 nM), whereas they were similar in potency on the alpha1beta3gamma2 subtype (IC50 values of 16-33 nM) and highly selective on the native receptor (IC50 values of 7.3, 306, and 2470 nM, respectively). The selectivity order for 29 insecticides and convulsants as IC50 ratios for native/beta3 or alpha1beta3gamma2/beta3 was as follows: fipronil > lindane > 19 other insecticides including alpha-endosulfan and picrotoxinin > 4 trioxabicyclooctanes and dithianes (almost nonselective) > tetramethylenedisulfotetramine, 4-chlorophenylsilatrane, or alpha-thujone. Specificity between mammals and insects at the target site (fipronil > lindane > alpha-endosulfan) paralleled that for toxicity. Potency at the native receptor is more predictive for inhibition of GABA-stimulated chloride uptake than that at the beta3 or alpha1beta3gamma2 receptors. Therefore, the beta3 subunit contains the insecticide target and other subunits differentially modulate the binding to confer compound-dependent specificity and selective toxicity.

  3. Phenotypic consequences of deletion of the {gamma}{sub 3}, {alpha}{sub 5}, or {beta}{sub 3} subunit of the type A {gamma}-aminobutyric acid receptor in mice

    Energy Technology Data Exchange (ETDEWEB)

    Culia, C.T.; Stubbs, L.J.; Montgomery, C.S.; Russell, L.B.; Rinchik, E.M. [Oak Ridge National Lab., TN (United States)

    1994-03-29

    Three genes (Gabrg3, Gabra5, and Gabrb3) encoding the {gamma}{sub 3}, {alpha}{sub 5}, and {beta}{sub 3} subunits of the type A {gamma}-aminobutyric acid receptor, respectively, are known to map near the pink-eyed dilution (p) locus in mouse chromosome 7. This region shares homology with a segment of human chromosome 15 that is implicated in Angelman syndrome, an inherited neurobehavioral disorder. By mapping Gabrg3-Gabra5-Gabrb3-telomere. Like Gabrb3, neither the Gabra5 nor Gabrg3 gene is functionally imprinted in adult mouse brain. Mice deleted for all three subunits die at birth with a cleft palate, although there are rare survivors ({approximately} 5%) that do not have a cleft palate but do exhibit a neurological abnormality characterized by tremor, jerky gait, and runtiness. The authors have previously suggested that deficiency of the {beta}{sub 3} subunit may be responsible for the clefting defect. Most notably, however, in this report they describe mice carrying two overlapping, complementing p deletions that fail to express the {gamma}{sub 3} transcript, as well as mice from another line that express neither the {gamma}{sub 3} nor {alpha}{sub 5} transcripts. Surprisingly, mice from both of these lines are phenotypically normal and do not exhibit any of the neurological symptoms characteristic of the rare survivors that are deleted for all three ({gamma}{sub 3}, {alpha}{sub 5}, and {beta}{sub 3}) subunits. These mice therefore provide a whole-organism type A {gamma}-aminobutyric-acid receptor background that is devoid of any receptor subtypes that normally contain the {gamma}{sub 3} and/or {alpha}{sub 5} subunits. The absence of an overt neurological phenotype in mice lacking the {gamma}{sub 3} and/or {alpha}{sub 5} subunits also suggests that mutations in these genes are unlikely to provide useful animal models for Angelman syndrome in humans.

  4. All-trans retinoic acid modulates mitogen-activated protein kinase pathway activation in human scleral fibroblasts through retinoic acid receptor beta

    OpenAIRE

    Huo, Lijun; Cui, Dongmei; Yang, Xiao; Gao, Zhenya; Trier, Klaus; Zeng, Junwen

    2013-01-01

    Purpose All-trans retinoic acid (ATRA) is known to inhibit the proliferation of human scleral fibroblasts (HSFs) and to modulate the scleral intercellular matrix composition, and may therefore serve as a mediator for controlling eye growth. Cell proliferation is regulated by the mitogen-activated protein kinase (MAPK) pathway. The aim of the current study was to investigate whether changed activation of the MAPK pathway could be involved in the response of HSFs exposed to ATRA. Methods HSFs w...

  5. [Beta-3 adrenergic receptor--structure and role in obesity and metabolic disorders].

    Science.gov (United States)

    Wiejak, J; Wyroba, E

    1999-01-01

    Structure and essential motifs of beta 3-adrenergic receptor (known previously as atypical beta-AR), which plays a central role in regulation of lipid metabolism have been described. Obesity results from an imbalance between caloric intake and energy expenditure. The consequence of catecholamine activation of beta 3-AR is increased mobilization of fatty acids from triglyceride stores (lipolysis) in brown and white adipose tissue as well as increased fatty acid beta-oxidation and heat-production via UCP-1 (thermogenesis) in brown adipose tissue. A pharmacokinetic effects of beta 3-agonists and putative involvement of Trp/Arg mutation in beta 3-AR gene in obesity and another metabolic disorders have been discussed.

  6. Vasodilatory mechanisms of beta receptor blockade.

    OpenAIRE

    Rath, Géraldine; Balligand, Jean-Luc; Dessy, Chantal

    2012-01-01

    Beta-blockers are widely prescribed for the treatment of a variety of cardiovascular pathologies. Compared to traditional beta-adrenergic antagonists, beta-blockers of the new generation exhibit ancillary properties such as vasodilation through different mechanisms. This translates into a more favorable hemodynamic profile. The relative affinities of beta-adrenoreceptor antagonists towards the three beta-adrenoreceptor isotypes matter for predicting their functional impact on vasomotor contro...

  7. [Characterization of cDNA of T-cell receptor beta chain in rainbow trout].

    Science.gov (United States)

    Partula, S; Fellah, J S; de Guerra, A; Charlemagne, J

    1994-08-01

    Using a two-step PCR strategy, we have cloned several cDNA segments encoding the T-cell receptor beta chain in a Teleost fish, the rainbow trout (Oncorhynchus mykiss). The nine clones analyzed encode identical N-terminal-truncated V beta regions which present limited sequence similarities with several mammalian TcR V beta chains, from residue Tyr-35 to residue Ser-95. These V beta regions are followed by V beta-D beta-J beta-like regions which are different in all the sequenced clones, and by identical C beta regions. The trout C beta domain (156 amino acids) is most related to the chicken and to amphibian (axolotl) C beta domains but no cysteine residue appears in the hinge region. Like in other vertebrate C beta s, the TM region carries a positively charged lysine residue (Lys-271). The intracytoplasmic domain is virtually absent. The possibility to analyze the structure, expression and diversity of a T-cell receptor chain in a Teleost fish model will be important for our future understanding of the evolution of specific immune recognition in vertebrates. PMID:7882160

  8. Linoleic acid stimulates [Ca2+]i increase in rat pancreatic beta-cells through both membrane receptor- and intracellular metabolite-mediated pathways.

    Directory of Open Access Journals (Sweden)

    Yufeng Zhao

    Full Text Available The role of the free fatty acid (FFA receptor and the intracellular metabolites of linoleic acid (LA in LA-stimulated increase in cytosolic free calcium concentration ([Ca(2+]i was investigated. [Ca(2+]i was measured using Fura-2 as indicator in rat pancreatic β-cells in primary culture. LA (20 µM for 2 min stimulated a transient peak increase followed by a minor plateau increase in [Ca(2+]i. Elongation of LA stimulation up to 10 min induced a strong and long-lasting elevation in [Ca(2+]i. Activation of FFA receptors by the non-metabolic agonist GW9508 (40 µM for 10 min resulted in an increase in [Ca(2+]i similar to that of 2-min LA treatment. Inhibition of acyl-CoA synthetases by Triacsin C suppressed the strong and long-lasting increase in [Ca(2+]i. The increase in [Ca(2+]i induced by 2 min LA or GW9508 were fully eliminated by exhaustion of endoplasmic reticulum (ER Ca(2+ stores or by inhibition of phospholipase C (PLC. Removal of extracellular Ca(2+ did not influence the transient peak increase in [Ca(2+]i stimulated by 2 min LA or GW9508. The strong and long-lasting increase in [Ca(2+]i induced by 10 min LA was only partially suppressed by extracellular Ca(2+ removal or thapsigargin pretreatment, whereas remaining elevation in [Ca(2+]i was eliminated after exhaustion of mitochondrial Ca(2+ using triphenyltin. In conclusion, LA stimulates Ca(2+ release from ER through activation of the FFA receptor coupled to PLC and mobilizes mitochondrial Ca(2+ by intracellular metabolites in β-cells.

  9. Dynamin-association with agonist-mediated sequestration of beta-adrenergic receptor in single-cell eukaryote Paramecium.

    Science.gov (United States)

    Wiejak, Jolanta; Surmacz, Liliana; Wyroba, Elzbieta

    2004-04-01

    Evidence that dynamin is associated with the sequestration of the Paramecium beta(2)-adrenergic receptor (betaAR) immunoanalogue is presented. We previously reported a dramatic change in the distribution of betaAR analogue in the subcellular fractions upon isoproterenol treatment: it is redistributed from the membraneous to the cytosolic fraction, as revealed by quantitative image analysis of western blots. Here we confirm and extend this observation by laser scanning confocal and immunogold electron microscopy. In the presence of isoproterenol (10 micro mol l(-1)) betaAR translocated from the cell surface into dynamin-positive vesicles in the cytoplasmic compartment, as observed by dual fluorochrome immunolabeling in a series of the confocal optical sections. Colocalization of betaAR and dynamin in the tiny endocytic vesicles was detected by further electron microscopic studies. Generally receptor sequestration follows its desensitization, which is initiated by receptor phosphorylation by G-protein-coupled receptor kinase. We cloned and sequenced the gene fragment of 407 nucleotides homologous to the beta-adrenergic receptor kinase (betaARK): its deduced amino acid sequence shows 51.6% homology in 126 amino acids that overlap with the human betaARK2 (GRK3), and may participate in Paramecium betaAR desensitization. These results suggest that the molecular machinery for the desensitization/sequestration of the receptor immunorelated to vertebrate betaAR exists in unicellular PARAMECIUM:

  10. Monitoring of beta-receptor sensitivity in cardiac surgery

    DEFF Research Database (Denmark)

    Yndgaard, S; Lippert, F K; Bigler, Dennis Richard;

    1999-01-01

    To determine the repeatability of the hemodynamic response to repeated isoproterenol challenge doses to validate the standardized isoproterenol sensitivity test as an index of cardiovascular beta-receptor function....

  11. High-resolution mapping of the [gamma]-aminobutyric acid receptor subunit [beta]3 and [alpha]5 gene cluster on chromosome 15q11-q13, and localization of breakpoints in two Angelman syndrome patients

    Energy Technology Data Exchange (ETDEWEB)

    Sinnett, D.; Wagstaff, J.; Woolf, E. (Children' s Hospital, Boston, MA (United States) Harvard Medical School, Boston, MA (United States)); Glatt, K. (Children' s Hospital, Boston, MA (United States)); Kirkness, E.J. (National Inst. of Alcohol Abuse and Alcoholism, Rockville, MD (United States))Lalande, M. (Children' s Hospital, Boston, MA (United States) Harvard Medical School, Boston, MA (United States) Howard Hughes Medical Inst., Boston, MA (United States))

    1993-06-01

    The [gamma]-aminobutyric acid (GABA[sub A]) receptors are a family of ligand-gated chloride channels constituting the major inhibitory neurotransmitter receptors in the nervous system. In order to determine the genomic organization of the GABA[sub A] receptor [beta]3 subunit gene (GABRB3) and [alpha]5 subunit gene (GABRA5) in chromosome 15q11-q13, the authors have constructed a high-resolution physical map using the combined techniques of field-inversion gel electrophoresis and phage genomic library screening. This map, which covers nearly 1.0 Mb, shows that GABRB3 and GABRA5 are separated by less than 100 kb and are arranged in a head-to-head configuration. GABRB3 encompasses approximately 250 kb, while GABRA5 is contained within 70 kb. This difference in size is due in large part to an intron of 150 kb within GABRB3. The authors have also identified seven putative CpG islands within a 600-kb interval. Chromosomal rearrangement breakpoints -- in one Angelman syndrome (AS) patient with an unbalanced translocation and in another patient with a submicroscopic deletion -- are located within the large GABRB3 intron. These findings will facilitate chromosomal walking strategies for cloning the regions disrupted by the DNA rearrangements in these AS patients and will be valuable for mapping new genes to the AS chromosomal region. 64 refs., 6 figs., 2 tabs.

  12. GPCR engineering yields high-resolution structural insights into beta2-adrenergic receptor function

    DEFF Research Database (Denmark)

    Rosenbaum, Daniel M; Cherezov, Vadim; Hanson, Michael A;

    2007-01-01

    of the reported high-resolution structure of beta2AR-T4L provides insights into inverse-agonist binding and the structural changes required to accommodate catecholamine agonists. Amino acids known to regulate receptor function are linked through packing interactions and a network of hydrogen bonds, suggesting...

  13. Regulating Chondrogenesis of Human Mesenchymal Stromal Cells with a Retinoic Acid Receptor-Beta Inhibitor: Differential Sensitivity of Chondral Versus Osteochondral Development

    Directory of Open Access Journals (Sweden)

    Solvig Diederichs

    2014-05-01

    Full Text Available Aim: Main objective was to investigate whether the synthetic retinoic acid receptor (RAR-β antagonist LE135 is able to drive in vitro chondrogenesis of human mesenchymal stromal cells (MSCs or improve differentiation by suppressing hypertrophic chondrocyte development. Methods: Chondrogenesis of human bone marrow and adipose tissue-derived MSCs was induced in micromass pellet culture for six weeks. Effects of LE135 alone and in combinatorial treatment with TGF-β on deposition of cartilaginous matrix including collagen type II and glycosaminoglycans, on deposition of non-hyaline cartilage collagens type I and X, and on hypertrophy markers including alkaline phosphatase (ALP, indian hedghehog (IHH and matrix metalloproteinase (MMP-13 were assessed. Results: LE135 was no inducer of chondrogenesis and failed to stimulate deposition of collagen type II and glycosaminoglycans. Moreover, addition of LE135 to TGF-β-treated pellets inhibited cartilaginous matrix deposition and gene expression of COL2A1. In contrast, non-hyaline cartilage collagens were less sensitive to LE135 and hypertrophy markers remained unaffected. Conclusion: This demonstrates a differential sensitivity of chondral versus endochondral differentiation pathways to RARβ signaling; however, opposite to the desired direction. The relevance of trans-activating versus trans-repressing RAR signaling, including effects on activator protein (AP-1 is discussed and implications for overcoming current limits of hMSC chondrogenesis are considered.

  14. Homology modeling of human alpha 1 beta 2 gamma 2 and house fly beta 3 GABA receptor channels and Surflex-docking of fipronil.

    Science.gov (United States)

    Cheng, Jin; Ju, Xiu-Lian; Chen, Xiang-Yang; Liu, Gen-Yan

    2009-09-01

    To further explore the mechanism of selective binding of the representative gamma-aminobutyric acid receptors (GABARs) noncompetitive antagonist (NCA) fipronil to insect over mammalian GABARs, three-dimensional models of human alpha 1 beta 2 gamma 2 and house fly beta 3 GABAR were generated by homology modeling, using the cryo-electron microscopy structure of the nicotinic acetylcholine receptor (nAChR) of Torpedo marmorata as a template. Fipronil was docked into the putative binding site of the human alpha 1 beta 2 gamma 2 and house fly beta 3 receptors by Surflex-docking, and the calculated docking energies are in agreement with experimental results. The GABA receptor antagonist fipronil exhibited higher potency with house fly beta 3 GABAR than with human alpha 1 beta 2 gamma 2 GABAR. Furthermore, analyses of Surflex-docking suggest that the H-bond interaction of fipronil with Ala2 and Thr6 in the second transmembrane segment (TM2) of these GABARs plays a relatively important role in ligand selective binding. The different subunit assemblies of human alpha 1 beta 2 gamma 2 and house fly beta 3 GABARs may result in differential selectivity for fipronil.

  15. Changes of lymphocyte beta-adrenergic receptors after surgical stress.

    Science.gov (United States)

    Eandi, M; Buraglio, M; Arduino, C; Viano, I; Sansalvadore, G; Arbinolo, M A

    1984-01-01

    In this study the authors' purpose was to observe the effects of surgical stress on the number of lymphocyte beta-adrenergic receptors in hypertensive and normotensive subjects. It was noticed that after surgery a significant reduction occurred in the number of binding sites of lymphocytes of both hypertensive and normotensive subjects. The time course of recovery to the pre-operative values of binding sites varied between the two groups, being slower in normotensive than in hypertensive patients. This might suggest a different pattern of regulation of the beta-adrenergic receptor between hypertensive and normotensive subjects.

  16. The pharmacology of spontaneously open alpha 1 beta 3 epsilon GABA A receptor-ionophores.

    Science.gov (United States)

    Maksay, Gábor; Thompson, Sally A; Wafford, Keith A

    2003-06-01

    Human alpha(1)beta(3) epsilon GABA(A) receptors were expressed in Xenopus oocytes and examined using the conventional two-electrode voltage-clamp technique and compared to alpha(1)beta(3)gamma(2) receptors. The effects of several GABA(A) agonists were studied, and the allosteric modulation of the channel by a number of GABAergic modulators investigated. The presence of the epsilon subunit increased the potency and efficacy of direct activation by partial GABA(A) agonists (piperidine-4-sulphonic acid and thio-4-PIOL), pentobarbital and neuro-steroids. Direct activation by 3-hydroxylated neurosteroids was restricted to 3alpha epimers, while chirality at C5 was indifferent. The 3beta-sulfate esters of pregnenolone and dehydroepiandrosterone inhibited the spontaneous currents with efficacies higher, while bicuculline methiodide and SR 95531 did so lower than picrotoxin and TBPS. Furosemide, fipronil, triphenylcyanoborate and Zn(2+) blocked the spontaneous currents of alpha(1)beta(3) epsilon receptors with different efficacies. Flunitrazepam and 4'-chlorodiazepam inhibited the spontaneous currents with micromolar potencies. In conclusion, spontaneously active alpha(1)beta(3) epsilon GABA(A) receptors can be potentiated and blocked by GABAergic agents within a broad range of efficacy.

  17. The role of Estrogen Receptor Beta in Prostate Cancer.

    OpenAIRE

    Christoforou, Paraskevi; Christopoulos, Panagiotis F; Koutsilieris, Michael

    2014-01-01

    Although androgen receptor (AR) signaling is the main molecular tool regulating growth and function of prostate gland, estrogen receptor beta (ERβ) is involved contributive in the differentiation of prostatic epithelial cells and numerous antiproliferative actions on prostate cancer cells. However, ERβ splice variants have been associated with prostate cancer initiation and progression mechanisms. Nowadays, ERß is a promising target as an anticancer therapy and prevention for prostate cancer....

  18. Estrogen receptor beta treats Alzheimer's disease

    Institute of Scientific and Technical Information of China (English)

    Zhu Tian; Jia Fan; Yang Zhao; Sheng Bi; Lihui Si; Qun Liu

    2013-01-01

    In vitro studies have shown that estrogen receptor β can attenuate the cytotoxic effect of amyloid β protein on PC12 cells through the Akt pathway without estrogen stimulation. In this study, we aimed to observe the effect of estrogen receptor β in Alzheimer's disease rat models established by intraventricular injection of amyloid β protein. Estrogen receptor β lentiviral particles delivered via intraventricular injection increased Akt content in the hippocampus, decreased interleukin-1β mRNA, tumor necrosis factor α mRNA and amyloid β protein levels in the hippocampus, and improved the learning and memory capacities in Alzheimer's disease rats. Estrogen receptor β short hairpin RNA lentiviral particles delivered via intraventricular injection had none of the above impacts on Alzheimer's disease rats. These experimental findings indicate that estrogen receptor β, independent from estrogen, can reduce inflammatory reactions and amyloid β deposition in the hippocampus of Alzheimer's disease rats, and improve learning and memory capacities. This effect may be mediated through activation of the Akt pathway.

  19. The human [gamma]-aminobutyric acid receptor subunit [beta]3 and [alpha]5 gene cluster in chromosome 15q11-q13 is rich in highly polymorphic (CA)[sub n] repeats

    Energy Technology Data Exchange (ETDEWEB)

    Glatt, K.; Lalande, M. (Howard Hughes Medical Institute, Boston, MA (United States)); Sinnett, D. (Harvard Medical School, Boston, MA (United States))

    1994-01-01

    The [gamma]-aminobutyric acid (GABA[sub A]) receptor [beta]33 (GABRB3) and [alpha]5 (GABRA5) subunit genes have been localized to the Angelman and Prader-Willi syndrome region of chromosome 15q11-q13. GABRB3, which encompasses 250 kb, is located 100 kb proximal of GABRA5, with the two genes arranged in head-to-head transcriptional orientation. In screening 135 kb of cloned DNA within a 260-kb interval extending from within GABRB3 to the 5[prime] end of GABRA5, 10 new (CA), repeats have been identified. Five of these have been analyzed in detail and found to be highly polymorphic, with the polymorphism information content (PIC) ranging from 0.7 to 0.85 and with heterozygosities of 67 to 94%. In the clones from GABRB3/GABRA5 region, therefore, the frequency of (CA)[sub n] with PICs [ge] 0.7 is 1 per 27 kb. Previous estimates of the density of (CA)[sub n] with PICs [ge] 0.7 in the human genome have been approximately 10-fold lower. The GABRB3/GABRA5 region appears, therefore, to be enriched for highly informative (CA)[sub n]. This set of closely spaced, short tandem repeat polymorphisms will be useful in the molecular analyses of Prader-Willi and Angelman syndromes and in high-resolution studies of genetic recombination within this region. 21 refs., 2 figs., 1 tab.

  20. Receptor-mediated delivery of all-trans-retinoic acid (ATRA) to hepatocytes from ATRA-loaded poly(N-p-vinylbenzyl-4-o-{beta}-D-galactopyranosyl-D-gluconamide) nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Seog-Jin [School of Agricultural Biotechnology, Seoul National University, Seoul 151-742 (Korea, Republic of) ; Moon, Hyun-Seuk [School of Agricultural Biotechnology, Seoul National University, Seoul 151-742 (Korea, Republic of) ; Guo, Ding-Ding [School of Agricultural Biotechnology, Seoul National University, Seoul 151-742 (Korea, Republic of) ; Kim, Sang-Heon [Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of) ; Akaike, Toshihiro [Department of Biomolecular Engineering, Tokyo Institute of Technology, Yokohama 226-8501 (Japan); Cho, Chong-Su [School of Agricultural Biotechnology, Seoul National University, Seoul 151-742 (Korea, Republic of) ]. E-mail: chocs@plaza.snu.ac.kr

    2006-01-15

    All-trans-retinoic acid (ATRA) plays a role in regulating CYP26 gene expression in hepatocytes. Poly(N-p-vinylbenzyl-4-o-{beta}-D-galactopyranosyl-D-gluconamide) (PVLA) nanoparticles have been used as hepatocyte-specific targeting candidates. The objective of this study was to investigate receptor-mediated delivery of ATRA using PVLA nanoparticles. ATRA-loaded PVLA nanoparticles were confirmed by {sup 1}H-nuclear magnetic resonance ({sup 1}H-NMR) and powder X-ray diffraction (XRD). In the {sup 1}H-NMR study, the proton signals of ATRA disappeared in the spectrum of ATRA-loaded PVLA nanoparticles in D{sub 2}O, whereas in dimethylsulfoxide-d{sub 6}, the spectrum seemed like an addition of the respective spectrum of each of the pure components. The crystalline peaks of ATRA disappeared in the XRD pattern of ATRA-loaded PVLA nanoparticles after ATRA was loaded into PVLA nanoparticles. In the measurement of size distribution, diameter of PVLA and ATRA-loaded PVLA nanoparticles in aqueous solution was 6.9 and 61.2 nm in number average, respectively. Flow cytometric analysis showed that the internalization of FITC-PVLA nanoparticles by hepatocytes in the absence of a competitive inhibitor was larger than preincubated with galactose. In reverse transcription-polymerase chain reaction (RT-PCR) analysis, ATRA-loaded PVLA nanoparticles induced CYP26A1 gene in hepatocytes in the absence of a competitive inhibitor but not preincubated with galactose. The results indicate that the ATRA-loaded PVLA nanoparticle can induce CYP26A1 gene in aqueous phase by an asialoglycoprotein receptor (ASGPR)-mediated delivery system.

  1. DMPD: TGF-beta signaling from receptors to the nucleus. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 10611754 TGF-beta signaling from receptors to the nucleus. Roberts AB. Microbes Inf...leus. PubmedID 10611754 Title TGF-beta signaling from receptors to the nucleus. Authors Roberts AB. Publicat

  2. The disintegrin and metalloproteinase ADAM12 contributes to TGF-beta signaling through interaction with the type II receptor

    DEFF Research Database (Denmark)

    Atfi, Azeddine; Dumont, Emmanuelle; Colland, Frédéric;

    2007-01-01

    Transforming growth factor-beta (TGF-beta) regulates a wide variety of biological processes through two types of Ser/Thr transmembrane receptors: the TGF-beta type I receptor and the TGF-beta type II receptor (TbetaRII). Upon ligand binding, TGF-beta type I receptor activated by TbetaRII propagat...

  3. Excitatory amino acid receptor antagonists

    DEFF Research Database (Denmark)

    Johansen, T N; Frydenvang, Karla Andrea; Ebert, B;

    1997-01-01

    We have previously shown that (RS)-2-amino-2-(5-tert-butyl-3-hydroxyisoxazol-4-yl)acetic acid (ATAA) is an antagonist at N-methyl-D-aspartic acid (NMDA) and (RS)-2-amino-3-(3-hydroxy-5-methylisoxazol-4-yl)propionic acid (AMPA) receptors. We have now resolved ATAA via diastereomeric salt formation......)-phenylethylamine salt of N-BOC-(R)-ATAA. Like ATAA, neither (R)- nor (S)-ATAA significantly affected (IC50 > 100 microM) the receptor binding of tritiated AMPA, kainic acid, or (RS)-3-(2-carboxypiperazin-4-yl)propyl-1-phosphonic acid, the latter being a competitive NMDA antagonist. Electrophysiological experiments......, using the rat cortical wedge preparation, showed the NMDA antagonist effect as well as the AMPA antagonist effect of ATAA to reside exclusively in the (R)-enantiomer (Ki = 75 +/- 5 microM and 57 +/- 1 microM, respectively). Neither (R)- nor (S)-ATAA significantly reduced kainic acid-induced excitation...

  4. Biological significance of glucocorticoid receptor beta

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Alternative splicing of the human glucocorticoid receptor (hGR) primary transcript produces two receptor isoforms, termed hGRα and hGRβ. hGRα is a ligand-activated transcription factor which, in the hormone-bound state, modulates the expression of glucocorticoid-responsive genes by binding to specific glucocorticoid response element (GRE) DNA sequences. In contrast, hGRβ dose not bind glucocorticoids and is transcriptionally inactive. We demonstrate here that hGRβ inhibits the hormone-induced, hGRα-mediated stimulations of gene expression, including glucocorticoid-responsive reporter gene (cat) and endogenous p21 gene. We also demonstrate that hGRβ can inhibit hGRα-mediated regulation of proliferation and differentiation of a human osteosarcoma cell line (HOS-8603). Our studies on the expression of hGR mRNA in nephrotic syndrome patients indicate that the hGRα/hGRβ mRNA ratio in peripheral white blood cell of hormone-resistant patients is lower than that of hormone-sensitive patients and health volunteers. These results indicate that hGRβ may be a physiologically and pathophysiologically relevant endogenous inhibitor of hGRα

  5. Characterization of glucagon-like peptide-1 receptor beta-arrestin 2 interaction: a high-affinity receptor phenotype

    DEFF Research Database (Denmark)

    Jorgensen, Rasmus; Martini, Lene; Schwartz, Thue W;

    2005-01-01

    To dissect the interaction between beta-arrestin ((beta)arr) and family B G protein-coupled receptors, we constructed fusion proteins between the glucagon-like peptide 1 receptor and (beta)arr2. The fusion constructs had an increase in apparent affinity selectively for glucagon, suggesting that (...

  6. [Changes of circulation, blood gases, acid-base-and metabolism during neurolept-analgesia with and without beta-receptor blockers in electro coagulation of Gasser's ganglion (author's transl)].

    Science.gov (United States)

    Knitza, R; Olbermann, M; Fischer, F; Bässler, K H

    1978-05-01

    The cardiovascular, blood gas, acid-base and metabolic changes occurring during operative stress were studied in 10 elderly, metabolically healthy patients, suffering from idiopathic trigeminal neuralgia, who underwent electrocoagulation of the gasserian ganglion under neuroleptanalgesia. In a group of 12 patients undergoing the same operative procedure and anesthesthetic management, we investigated the effects of administration of a beta blocking agent on these parameters. Intraoperative rises of blood pressure and tachycardia were prevented by intravenous administration of 0.4 mg Pindolol (Visken), whereas increases in the blood glucose levels at the end of the operation were the same. The increase of glycerol, free fatty acids and ketone bodies was markedly reduced after pretreatment with the beta blocker compared with the controlgroup. In the patients without beta blocker treatment pH and standard bicarbonate at the end of the operation were lower as the result of the stimulation of ketogenesis. PMID:27127

  7. Antithrombotic effects of beta2-adrenergic receptor blockade on top of beta1-receptor blockade in patients with acute coronary syndrome or heart failure : a systematic review

    NARCIS (Netherlands)

    De Peuter, O.R.; Lussana, F.; Peters, R.J.; Büller, H.R.; Kamphuisen, P.W.

    2009-01-01

    Background: Non-selective beta1 + 2 blockers may have specific antithrombotic effects not present in eta1-blockers, due to a eta2-specific effect on sympathetic activity. Our aim was to assess the influence of eta2-receptor suppression on top of selective beta1-receptor blockade on the occurrence of

  8. Expression of transforming growth factor beta (TGF beta) receptors and expression of TGF beta 1, TGF beta 2 and TGF beta 3 in human small cell lung cancer cell lines

    DEFF Research Database (Denmark)

    Damstrup, L; Rygaard, K; Spang-Thomsen, M;

    1993-01-01

    A panel of 21 small cell lung cancer cell (SCLC) lines were examined for the presence of Transforming growth factor beta receptors (TGF beta-r) and the expression of TGF beta mRNAs. By the radioreceptor assay we found high affinity receptors to be expressed in six cell lines. scatchard analysis...... of the binding data demonstrated that the cells bound between 4.5 and 27.5 fmol mg-1 protein with a KD ranging from 16 to 40 pM. TGF beta 1 binding to the receptors was confirmed by cross-linking TGF beta 1 to the TGF beta-r. Three classes of TGF beta-r were demonstrated, type I and type II receptors with M......(r) = 65,000 and 90,000 and the betaglycan (type III) with M(r) = 280,000. Northern blotting showed expression of TGF beta 1 mRNA in ten, TGF beta 2 mRNA in two and TGF beta 3 mRNA in seven cell lines. Our results provide, for the first time, evidence that a large proportion of a broad panel of SCLC cell...

  9. Ellagic acid promotes A{beta}42 fibrillization and inhibits A{beta}42-induced neurotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Ying [Department of Histology and Embryology, College of Basic Medical Science, China Medical University, Shenyang 110001 (China); Tsinghua University School of Medicine, Haidian District, Beijing 100084 (China); Yang, Shi-gao; Du, Xue-ting; Zhang, Xi; Sun, Xiao-xia; Zhao, Min [Tsinghua University School of Medicine, Haidian District, Beijing 100084 (China); Sun, Gui-yuan, E-mail: sungy2004@sohu.com [Department of Histology and Embryology, College of Basic Medical Science, China Medical University, Shenyang 110001 (China); Liu, Rui-tian, E-mail: rtliu@tsinghua.edu.cn [Tsinghua University School of Medicine, Haidian District, Beijing 100084 (China)

    2009-12-25

    Smaller, soluble oligomers of {beta}-amyloid (A{beta}) play a critical role in the pathogenesis of Alzheimer's disease (AD). Selective inhibition of A{beta} oligomer formation provides an optimum target for AD therapy. Some polyphenols have potent anti-amyloidogenic activities and protect against A{beta} neurotoxicity. Here, we tested the effects of ellagic acid (EA), a polyphenolic compound, on A{beta}42 aggregation and neurotoxicity in vitro. EA promoted A{beta} fibril formation and significant oligomer loss, contrary to previous results that polyphenols inhibited A{beta} aggregation. The results of transmission electron microscopy (TEM) and Western blot displayed more fibrils in A{beta}42 samples co-incubated with EA in earlier phases of aggregation. Consistent with the hypothesis that plaque formation may represent a protective mechanism in which the body sequesters toxic A{beta} aggregates to render them harmless, our MTT results showed that EA could significantly reduce A{beta}42-induced neurotoxicity toward SH-SY5Y cells. Taken together, our results suggest that EA, an active ingredient in many fruits and nuts, may have therapeutic potential in AD.

  10. Development and validation of fluorescent receptor assays based on the human recombinant estrogen receptor subtypes alpha and beta

    NARCIS (Netherlands)

    de boer, T; Otjens, D; Muntendam, A; Meulman, E; van Oostijen, M; Ensing, K

    2004-01-01

    This article describes the development and validation of two fluorescent receptor assays for the hRec-estrogen receptor subtypes alpha and beta. As a labelled ligand an autofluorescent phyto-estrogen (coumestrol) has been used. The estrogen receptor (ER) belongs to the nuclear receptor family, a cla

  11. Subtype selective kainic acid receptor agonists

    DEFF Research Database (Denmark)

    Bunch, Lennart; Krogsgaard-Larsen, Povl

    2009-01-01

    (S)-Glutamic acid (Glu) is the major excitatory neurotransmitter in the mammalian central nervous system, activating the plethora of glutamate receptors (GluRs). In broad lines, the GluRs are divided into two major classes: the ionotropic Glu receptors (iGluRs) and the metabotropic Glu receptors ...

  12. Expression of retinoic acid receptors in human endometrial carcinoma.

    Science.gov (United States)

    Tanabe, Kojiro; Utsunomiya, Hiroki; Tamura, Mitsutoshi; Niikura, Hitoshi; Takano, Tadao; Yoshinaga, Kohsuke; Nagase, Satoru; Suzuki, Takashi; Ito, Kiyoshi; Matsumoto, Mitsuyo; Hayashi, Shin-ichi; Yaegashi, Nobuo

    2008-02-01

    The retinoids (vitamin A and its biologically active derivatives) are essential for the health and survival of the individual. Several studies have reported a strong rationale for the use of retinoids in cancer treatment and chemoprevention. It has been discovered that expression of retinoic acid receptor (RAR) beta is frequently silenced in epithelial carcinogenesis, which has led to the hypothesis that RAR beta could act as a tumor suppressor. However, the status of RAR beta in human endometrial carcinoma has not been examined. In the present study, we initially studied the effects of retinoic acid on cell proliferation and the expression of RAR alpha, RAR beta, and RAR gamma using AM580 (a RAR-specific agonist) in the Ishikawa endometrial cancer cell line. We also examined the expression of RAR in human eutopic endometrium (30 cases), endometrial hyperplasia (28 cases), and endometrial carcinoma (103 cases) using immunohistochemistry. Finally, we correlated these findings with the clinicopathological parameters. In vitro, cell growth was inhibited and RAR beta and RAR gamma mRNA was significantly induced by AM580, compared with vehicle controls, whereas RAR alpha mRNA was significantly attenuated by AM580, compared with vehicle. RAR beta was detected predominantly in endometrial hyperplasia, compared with endometrial carcinoma. No statistically significant correlation was obtained between the expression of any other RAR subtypes and clinicopathological parameters in human endometrial carcinoma. The results of our study demonstrate that AM580 inhibits cell growth and induces RAR beta mRNA expression in the Ishikawa cell line, and the expression level of RAR beta in endometrial carcinoma is significantly lower than that in endometrial hyperplasia. AM580 might therefore be considered as a potential treatment for endometrial carcinoma.

  13. A member of the TGF-beta receptor gene family in the parasitic nematode Brugia pahangi.

    Science.gov (United States)

    Gomez-Escobar, N; van den Biggelaar, A; Maizels, R

    1997-10-15

    The full length cDNA sequence of a Type I transforming growth factor-beta (TGF-beta) receptor has been isolated from the filarial parasitic nematode Brugia pahangi. This new gene, designated Bp-trk-1, encodes a predicted 645 amino acid sequence with an N-terminal hydrophobic stretch which may act as a signal peptide. The extracellular portion (residues 15-187) is cysteine-rich and has three potential N-glycosylation sites. At positions 250-255 the protein contains the glycine-serine rich motif characteristic of Type I receptors. The closest homologue is a Caenorhabditis elegans gene (Q09488) in cosmid C32D5.2 which shares 67% amino acid identity with Bp-trk-1 in the most conserved kinase domain (aa 259-482). Other type I receptors such as C. elegans daf-1 and Drosophila tkv show 38-53% identity in the same region. Some residues conserved in Drosophila and vertebrates are not present in the B. pahangi sequence. RT-PCR amplification has been used to show that the transcript is expressed in the three main stages of the B. pahangi life cycle: microfilariae, infective larvae and adults. The ligand remains unknown at this time but is likely to be most similar to that for C. elegans Q09488. PMID:9358045

  14. Beta-Adrenergic Receptor Expression in Muscle Cells

    Science.gov (United States)

    Young, Ronald B.; Bridge, K.; Vaughn, J. R.

    1999-01-01

    beta-adrenergic receptor (bAR) agonists presumably exert their physiological action on skeletal muscle cells through the bAR. Since the signal generated by the bAR is cyclic AMP (cAMP), experiments were initiated in primary chicken muscle cell cultures to determine if artificial elevation of intracellular cAMP by treatment with forskolin would alter the population of bAR expressed on the surface of muscle cells. Chicken skeletal muscle cells after 7 days in culture were employed for the experiments because muscle cells have attained a steady state with respect to muscle protein metabolism at this stage. Cells were treated with 0-10 uM forskolin for a total of three days. At the end of the 1, 2, and 3 day treatment intervals, the concentration of cAMP and the bAR population were measured. Receptor population was measured in intact muscle cell cultures as the difference between total binding of [H-3]CGP-12177 and non-specific binding of [H-3]CGP-12177 in the presence of 1 uM propranolol. Intracellular cAMP concentration was measured by radioimmunoassay. The concentration of cAMP in forskolin-treated cells increased up to 10-fold in a dose dependent manner. Increasing concentrations of forskolin also led to an increase in (beta)AR population, with a maximum increase of approximately 50% at 10 uM. This increase in (beta)AR population was apparent after only 1 day of treatment, and the pattern of increase was maintained for all 3 days of the treatment period. Thus, increasing the intracellular concentration of cAMP leads to up-regulation of (beta)AR population. Clenbuterol and isoproterenol gave similar effects on bAR population. The effect of forskolin on the quantity and apparent synthesis rate of the heavy chain of myosin (mhc) were also investigated. A maximum increase of 50% in the quantity of mhc was observed at 0.2 UM forskolin, but higher concentrations of forskolin reduced the quantity of mhc back to control levels.

  15. Shared receptor components but distinct complexes for alpha and beta interferons.

    Science.gov (United States)

    Lewerenz, M; Mogensen, K E; Uzé, G

    1998-09-25

    The type I interferon family includes 13 alpha, one omega and one beta subtypes recognized by a complex containing the receptor subunits ifnar1 and ifnar2 and their associated Janus tyrosine kinases, Tyk2 and Jak1. To investigate the reported differences in the way that alpha and beta interferons signal through the receptor, we introduced alanine-substitutions in the ifnar2 extracellular domain, and expressed the mutants in U5A cells, lacking endogenous ifnar2. A selection, designed to recover mutants that responded preferentially to alpha or beta interferon yielded three groups: I, neutral; II, sensitive to alpha interferon, partially resistant to beta interferon; III, resistant to alpha interferon, partially sensitive to beta interferon. A mutant clone, TMK, fully resistant to alpha interferon with good sensitivity to beta interferon, was characterized in detail and compared with U5A cells complemented with wild-type ifnar2 and also with Tyk2-deficient 11.1 cells, which exhibit a similar alpha-unresponsive phenotype with a partial beta interferon response. Using anti-receptor antibodies and mutant forms of beta interferon, three distinct modes of ligand interaction could be discerned: (i) alpha interferon with ifnar1 and ifnar2; (ii) beta interferon with ifnar1 and ifnar2; (iii) beta interferon with ifnar2 alone. We conclude that alpha and beta interferons signal differently through their receptors because the two ligand subtypes interact with the receptor subunits ifnar 1 and ifnar2 in entirely different ways.

  16. Immune Modulation by Different Types of beta 2 -> 1-Fructans Is Toll-Like Receptor Dependent

    NARCIS (Netherlands)

    Vogt, L.; Ramasamy, U.; Meyer, Diederick; Pullens, G.; Venema, K.; Faas, M.M.; Schols, H.A.; de Vos, P.

    2013-01-01

    Introduction: beta 2 -> 1-fructans are dietary fibers. Main objectives of this study were 1) to demonstrate direct signalling of beta 2 -> 1-fructans on immune cells, 2) to study whether this is mediated by the pattern recognition receptors Toll-like receptors (TLRs) and nucleotide-binding oligomeri

  17. Simultaneous stimulation of GABA and beta adrenergic receptors stabilizes isotypes of activated adenylyl cyclase heterocomplex

    Directory of Open Access Journals (Sweden)

    Robichon Alain

    2004-06-01

    Full Text Available Abstract Background We investigated how the synthesis of cAMP, stimulated by isoproterenol acting through β-adrenoreceptors and Gs, is strongly amplified by simultaneous incubation with baclofen. Baclofen is an agonist of δ-aminobutyric acid type B receptors [GABAB], known to inhibit adenylyl cyclase via Gi. Because these agents have opposite effects on cAMP levels, the unexpected increase in cAMP synthesis when they are applied simultaneously has been intensively investigated. From previous reports, it appears that cyclase type II contributes most significantly to this phenomenon. Results We found that simultaneous application of isoproterenol and baclofen specifically influences the association/dissociation of molecules involved in the induction and termination of cyclase activity. Beta/gamma from [GABA]B receptor-coupled Gi has a higher affinity for adenylyl cyclase isoform(s when these isoforms are co-associated with Gs. Our data also suggest that, when beta/gamma and Gαs are associated with adenylyl cyclase isoform(s, beta/gamma from [GABA]B receptor-coupled Gi retards the GTPase activity of Gαs from adrenergic receptor. These reciprocal regulations of subunits of the adenylyl cyclase complex might be responsible for the drastic increase of cAMP synthesis in response to the simultaneous signals. Conclusions Simultaneous signals arriving at a particular synapse converge on molecular detectors of coincidence and trigger specific biochemical events. We hypothesize that this phenomenon comes from the complex molecular architectures involved, including scaffolding proteins that make reciprocal interactions between associated molecules possible. The biochemistry of simultaneous signaling is addressed as a key to synaptic function.

  18. The T cell receptor beta genes of Xenopus.

    Science.gov (United States)

    Chretien, I; Marcuz, A; Fellah, J; Charlemagne, J; Du Pasquier, L

    1997-03-01

    cDNA of the T cell receptor beta (TCRB) have been isolated from the anuran amphibian Xenopus and they show strong structural homology to TCRB sequences of other vertebrates. Ten BV families, two D segments, ten J segments, and a single C region have been defined so far. Each V family consists of one to two members per haploid genome. A unique feature of the Xenopus TCRB constant region is the lack of N-linked carbohydrate glycosylation sites. The recombination signal sequences suggest that the mechanism of rearrangements are identical to those of mammals. The locus is inherited in a diploid manner despite the pseudotetraploidy of the Xenopus laevis and X. gilli used in this study. PMID:9079820

  19. Role of retinoic acid receptors in squamous-cell carcinoma in human esophagus

    DEFF Research Database (Denmark)

    Bergheim, I.; Wolfgarten, E.; Bollschweiler, E.;

    2005-01-01

    BACKGROUND: Worldwide, cancer in the esophagus ranks among the 10 most common cancers. Alterations of retinoic acid receptors (e.g. RARalpha, beta, gamma, and RXRalpha, beta, gamma) expression is considered to play an important role in development of squamous-cell carcinoma (SCC), which is the most...... were found for RARalpha, beta, and RXRbeta protein levels between normal esophageal tissue of patients and that of controls. CONCLUSION: In conclusion, results of the present study suggest that alterations of retinoic acid receptors protein may contribute in the development of SCC in esophagus...... and that in some patients life style (e.g. smoking and alcohol consumption) may be a critical component in the alteration of retinoic acid receptor levels in esophagus....

  20. Random length assortment of human and mouse T cell receptor for antigen alpha and beta chain CDR3.

    Science.gov (United States)

    Johnson, G; Wu, T T

    1999-10-01

    In view of the recently determined three-dimensional structures of complexes formed by the T cell receptor for antigen (TCR), the processed peptide and the MHC class I molecule, it is expected that the combined configuration formed by the third complementarity determining regions (CDR3) of TCR alpha and beta chains will be very restricted in size and shape due to the limited length variations of the processed peptides. Thus, the combined TCR alpha and beta chain CDR3 lengths should have a fairly narrow distribution. This feature can be due to the selective association of long alpha chain CDR3 with short beta chain CDR3 and vice versa or due to random assortment of alpha and beta chain CDR3 of even narrower length distribution. Based on existing translated amino acid sequence data, it has been found that the latter mechanism is responsible.

  1. G-protein-coupled receptors for free fatty acids

    DEFF Research Database (Denmark)

    Milligan, Graeme; Ulven, Trond; Murdoch, Hannah;

    2014-01-01

    of these receptors. However, ongoing clinical trials of agonists of free fatty acid receptor 1 suggest that this receptor and other receptors for free fatty acids may provide a successful strategy for controlling hyperglycaemia and providing novel approaches to treat diabetes. Receptors responsive to free fatty acid...

  2. A CYCLIC-AMP RESPONSE ELEMENT IS INVOLVED IN RETINOIC ACID-DEPENDENT RAR-BETA-2 PROMOTER ACTIVATION

    NARCIS (Netherlands)

    KRUYT, FAE; FOLKERS, G; VANDENBRINK, CE; VANDERSAAG, PT; Kruyt, Frank

    1992-01-01

    Activation of the retinoic acid receptor (RAR) beta2 promoter is known to be mediated by a RA response element located in the proximity of the TATA-box. By deletion studies in P19 embryonal carcinoma cells we have analyzed the RARbeta2 promoter for the presence of additional regulatory elements. We

  3. Dynamic T-lymphocyte chemokine receptor expression induced by interferon-beta therapy in multiple sclerosis

    DEFF Research Database (Denmark)

    Krakauer, M; Sorensen, P S; Khademi, M;

    2006-01-01

    as these influence central nervous system (CNS) transmigration and inflammation. At 'steady state' (>/=1 day after the most recent IFN-beta injection), IFN-beta treatment increased CD4(+) T-cell surface expression of CC chemokine receptor (CCR)4, CCR5 and CCR7 after 3 months of treatment, whereas that of CXC...... and immunoregulatory genes. In conclusion, IFN-beta treatment caused 'steady-state' increases of several chemokine receptors relevant for CD4(+) T-lymphocyte trafficking and function, possibly facilitating lymphocyte migration into the CNS. An important therapeutic effect of IFN-beta treatment may be the normalization...... of a decreased Th2-related CD4(+) T-cell CCR4 expression in MS patients. Surface chemokine receptor expression and CXCL10 varied according to the timing of blood sampling in relation to the most recent IFN-beta injection. Thus, it is imperative to distinguish acute effects of IFN-beta from steady-state effects....

  4. HPLC Analysis of [Alpha]- and [Beta]-Acids in Hops

    Science.gov (United States)

    Danenhower, Travis M.; Force, Leyna J.; Petersen, Kenneth J.; Betts, Thomas A.; Baker, Gary A.

    2008-01-01

    Hops have been used for centuries to impart aroma and bitterness to beer. The cones of the female hop plant contain both essential oils, which include many of the fragrant components of hops, and a collection of compounds known as [alpha]- and [beta]-acids that are the precursors to bittering agents. In order for brewers to predict the ultimate…

  5. Targeting of beta adrenergic receptors results in therapeutic efficacy against models of hemangioendothelioma and angiosarcoma.

    Directory of Open Access Journals (Sweden)

    Jessica M Stiles

    Full Text Available Therapeutic targeting of the beta-adrenergic receptors has recently shown remarkable efficacy in the treatment of benign vascular tumors such as infantile hemangiomas. As infantile hemangiomas are reported to express high levels of beta adrenergic receptors, we examined the expression of these receptors on more aggressive vascular tumors such as hemangioendotheliomas and angiosarcomas, revealing beta 1, 2, and 3 receptors were indeed present and therefore aggressive vascular tumors may similarly show increased susceptibility to the inhibitory effects of beta blockade. Using a panel of hemangioendothelioma and angiosarcoma cell lines, we demonstrate that beta adrenergic inhibition blocks cell proliferation and induces apoptosis in a dose dependent manner. Beta blockade is selective for vascular tumor cells over normal endothelial cells and synergistically effective when combined with standard chemotherapeutic or cytotoxic agents. We demonstrate that inhibition of beta adrenergic signaling induces large scale changes in the global gene expression patterns of vascular tumors, including alterations in the expression of established cell cycle and apoptotic regulators. Using in vivo tumor models we demonstrate that beta blockade shows remarkable efficacy as a single agent in reducing the growth of angiosarcoma tumors. In summary, these experiments demonstrate the selective cytotoxicity and tumor suppressive ability of beta adrenergic inhibition on malignant vascular tumors and have laid the groundwork for a promising treatment of angiosarcomas in humans.

  6. Evidence for the presence of beta 3-adrenergic receptor mRNA in the human brain.

    Science.gov (United States)

    Rodriguez, M; Carillon, C; Coquerel, A; Le Fur, G; Ferrara, P; Caput, D; Shire, D

    1995-04-01

    The beta 3-adrenergic receptor (AR) is widely distributed in peripheral tissues, but up to now it has not been detected in the central nervous system. By using the polymerase chain reaction (PCR) technique, we found the beta 3-AR mRNA to be present in all the regions of the human brain we investigated. The quantities found were very low compared to those of the beta 1-AR and beta 2-AR mRNAs, being hardly detectable in adult brain. In contrast, the brain of very young infants contained about 100 times more beta 3-AR mRNA than the adult brain, whereas the amounts of beta 1-AR and beta 2-AR transcripts were essentially the same. In addition, using PCR we have cloned a central beta 3-AR coding region from a human frontal cortex cDNA library and have found it to be identical to the corresponding peripheral sequence. PMID:7609625

  7. Estrogen receptor beta is a novel therapeutic target for photoaging.

    Science.gov (United States)

    Chang, Ken C N; Wang, Yihe; Oh, Inn Gyung; Jenkins, Susan; Freedman, Leonard P; Thompson, Catherine C; Chung, Jin Ho; Nagpal, Sunil

    2010-05-01

    One of the many harmful factors faced by the skin is solar UV radiation, which damages skin by inducing chronic low-grade inflammation through increased expression of proinflammatory cytokines, metalloproteinases (MMPs) and cyclooxygenase-2 (COX-2). Estrogen receptors (ERs) alpha and beta are ligand-dependent transcription factors that are expressed in skin, and an ERbeta agonist has previously shown efficacy in vivo in models of pain and inflammation. Because ERbeta does not carry the breast and uterine proliferation liabilities of ERalpha, we decided to explore the possibility of using ERbeta as a target for photoaging. We show that ERbeta-selective compounds suppressed the expression of cytokines and MMPs in activated keratinocytes and fibroblast-based in vitro models of photoaging. Furthermore, in activated dermal fibroblasts, ERbeta-selective compounds also inhibited COX-2. These activities of ERbeta ligands in skin cells correlated with the expression levels of ERbeta and showed reversal by treatment with a potent synthetic ER antagonist. Furthermore, the pharmacology of ERbeta-selective compound was observed in wild-type but not in skin cells obtained from ERbeta knockout mice. Finally, we demonstrate that a synthetic ERbeta agonist inhibited UV-induced photodamage and skin wrinkle formation in a murine model of photoaging. Therefore, the potential of an ERbeta ligand to regulate multiple pathways underlying the cause of photoaging suggests ERbeta to be a novel therapeutic target for the prevention and treatment of photoaging. PMID:20110405

  8. Magnitude of a conformational change in the glycine receptor beta1-beta2 loop is correlated with agonist efficacy

    DEFF Research Database (Denmark)

    Pless, Stephan Alexander; Lynch, Joseph W

    2009-01-01

    associated with the closed-flip transition in the alpha1-glycine receptor. We employed voltage-clamp fluorometry to compare ligand-binding domain conformational changes induced by the following agonists, listed from highest to lowest affinity and efficacy: glycine > beta-alanine > taurine. Voltage...

  9. Complex Pharmacology of Free Fatty Acid Receptors

    DEFF Research Database (Denmark)

    Milligan, Graeme; Shimpukade, Bharat; Ulven, Trond;

    2016-01-01

    G protein-coupled receptors (GPCRs) are historically the most successful family of drug targets. In recent times it has become clear that the pharmacology of these receptors is far more complex than previously imagined. Understanding of the pharmacological regulation of GPCRs now extends beyond...... pharmacology have shaped understanding of the complex pharmacology of receptors that recognize and are activated by nonesterified or "free" fatty acids (FFAs). The FFA family of receptors is a recently deorphanized set of GPCRs, the members of which are now receiving substantial interest as novel targets...... for the treatment of metabolic and inflammatory diseases. Further understanding of the complex pharmacology of these receptors will be critical to unlocking their ultimate therapeutic potential....

  10. 18{beta}-Glycyrrhetinic acid inhibits adipogenic differentiation and stimulates lipolysis

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Myung-Hee; Jeong, Jae-Kyo; Lee, You-Jin; Seol, Jae-Won; Ahn, Dong-Choon; Kim, In-Shik [Center for Healthcare Technology Development, Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Jeonju, Jeonbuk 561-756 (Korea, Republic of); Park, Sang-Youel, E-mail: sypark@chonbuk.ac.kr [Center for Healthcare Technology Development, Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Jeonju, Jeonbuk 561-756 (Korea, Republic of)

    2012-04-20

    Highlights: Black-Right-Pointing-Pointer 18{beta}-GA inhibits adipogenic differentiation in 3T3-L1 preadipocytes and stimulates lipolysis in differentiated adipocytes. Black-Right-Pointing-Pointer Anti-adipogenic effect of 18{beta}-GA is caused by down-regulation of PPAR{gamma} and inactivation of Akt signalling. Black-Right-Pointing-Pointer Lipolytic effect of 18{beta}-GA is mediated by up-regulation of HSL, ATGL and perilipin and activation of HSL. -- Abstract: 18{beta}-Glycyrrhetinic acid (18{beta}-GA) obtained from the herb liquorice has various pharmacological properties including anti-inflammatory and anti-bacterial activities. However, potential biological anti-obesity activities are unclear. In this study, novel biological activities of 18{beta}-GA in the adipogenesis of 3T3-L1 preadipocytes and in lipolysis of differentiated adipocytes were identified. Mouse 3T3-L1 cells were used as an in vitro model of adipogenesis and lipolysis, using a mixture of insulin/dexamethasone/3-isobutyl-1-methylxanthine (IBMX) to induce differentiation. The amount of lipid droplet accumulation was determined by an AdipoRed assay. The expression of several adipogenic transcription factors and enzymes was investigated using real-time reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blotting. 18{beta}-GA dose-dependently (1-40 {mu}M) significantly decreased lipid accumulation in maturing preadipocytes. In 3T3-L1 preadipocytes, 10 {mu}M of 18{beta}-GA down-regulated the transcriptional levels of the peroxisome proliferator-activated receptor {gamma}, CCAAT/enhancer-binding protein {alpha} and adiponectin, which are markers of adipogenic differentiation via Akt phosphorylation. Also, in differentiated adipocytes, 18{beta}-GA increased the level of glycerol release and up-regulated the mRNA of hormone-sensitive lipase, adipose TG lipase and perilipin, as well as the phosphorylation of hormone-sensitive lipase at Serine 563. The results indicate that 18{beta

  11. Neofunctionalization in vertebrates: the example of retinoic acid receptors.

    Directory of Open Access Journals (Sweden)

    Hector Escriva

    2006-07-01

    Full Text Available Understanding the role of gene duplications in establishing vertebrate innovations is one of the main challenges of Evo-Devo (evolution of development studies. Data on evolutionary changes in gene expression (i.e., evolution of transcription factor-cis-regulatory elements relationships tell only part of the story; protein function, best studied by biochemical and functional assays, can also change. In this study, we have investigated how gene duplication has affected both the expression and the ligand-binding specificity of retinoic acid receptors (RARs, which play a major role in chordate embryonic development. Mammals have three paralogous RAR genes--RAR alpha, beta, and gamma--which resulted from genome duplications at the origin of vertebrates. By using pharmacological ligands selective for specific paralogues, we have studied the ligand-binding capacities of RARs from diverse chordates species. We have found that RAR beta-like binding selectivity is a synapomorphy of all chordate RARs, including a reconstructed synthetic RAR representing the receptor present in the ancestor of chordates. Moreover, comparison of expression patterns of the cephalochordate amphioxus and the vertebrates suggests that, of all the RARs, RAR beta expression has remained most similar to that of the ancestral RAR. On the basis of these results together, we suggest that while RAR beta kept the ancestral RAR role, RAR alpha and RAR gamma diverged both in ligand-binding capacity and in expression patterns. We thus suggest that neofunctionalization occurred at both the expression and the functional levels to shape RAR roles during development in vertebrates.

  12. Design and synthesis of carborane-containing estrogen receptor-beta (ERβ)-selective ligands.

    Science.gov (United States)

    Ohta, Kiminori; Ogawa, Takumi; Oda, Akifumi; Kaise, Asako; Endo, Yasuyuki

    2015-10-01

    Candidates for highly selective estrogen receptor-beta (ERβ) ligands (6a-c, 7a-c, 8a and 8b) were designed and synthesized based on carborane-containing ER ligands 1 and 2 as lead compounds. Among them, p-carboranylcyclohexanol derivatives 8a and 8b exhibited high ERβ selectivity in competitive binding assay: for example, 8a showed 56-fold selectivity for ERβ over ERα. Docking studies of 8a and 8b with the ERα and ERβ ligand-binding domains (LBDs) suggested that the p-carborane cage of the ligands is located close to key amino acid residues that influence ER-subtype selectivity, that is, Leu384 in the ERα LBD and Met336 in the ERβ LBD. The p-carborane cage in 8a and 8b appears to play a crucial role in the increased ERβ selectivity. PMID:26298498

  13. Azetidine-2-carboxylic acid in garden beets (Beta vulgaris).

    Science.gov (United States)

    Rubenstein, Edward; Zhou, Haihong; Krasinska, Karolina M; Chien, Allis; Becker, Christopher H

    2006-05-01

    Azetidine-2-carboxylic acid (L-Aze) is a toxic and teratogenic non-protein amino acid. In many species, including man, L-Aze is misincorporated into protein in place of proline, altering collagen, keratin, hemoglobin, and protein folding. In animal models of teratogenesis, it causes a wide range of malformations. The role of L-Aze in human disease has been unexplored, probably because the compound has not been associated with foods consumed by humans. Herein we report the presence of L-Aze in the garden or table beet (Beta vulgaris).

  14. Candidate Gene Study of TRAIL and TRAIL Receptors: Association with Response to Interferon Beta Therapy in Multiple Sclerosis Patients

    Science.gov (United States)

    Órpez-Zafra, Teresa; Pinto-Medel, María Jesús; Oliver-Martos, Begoña; Ortega-Pinazo, Jesús; Arnáiz, Carlos; Guijarro-Castro, Cristina; Varadé, Jezabel; Álvarez-Lafuente, Roberto; Urcelay, Elena; Sánchez-Jiménez, Francisca

    2013-01-01

    TRAIL and TRAIL Receptor genes have been implicated in Multiple Sclerosis pathology as well as in the response to IFN beta therapy. The objective of our study was to evaluate the association of these genes in relation to the age at disease onset (AAO) and to the clinical response upon IFN beta treatment in Spanish MS patients. We carried out a candidate gene study of TRAIL, TRAILR-1, TRAILR-2, TRAILR-3 and TRAILR-4 genes. A total of 54 SNPs were analysed in 509 MS patients under IFN beta treatment, and an additional cohort of 226 MS patients was used to validate the results. Associations of rs1047275 in TRAILR-2 and rs7011559 in TRAILR-4 genes with AAO under an additive model did not withstand Bonferroni correction. In contrast, patients with the TRAILR-1 rs20576-CC genotype showed a better clinical response to IFN beta therapy compared with patients carrying the A-allele (recessive model: p = 8.88×10−4, pc = 0.048, OR = 0.30). This SNP resulted in a non synonymous substitution of Glutamic acid to Alanine in position 228 (E228A), a change previously associated with susceptibility to different cancer types and risk of metastases, suggesting a lack of functionality of TRAILR-1. In order to unravel how this amino acid change in TRAILR-1 would affect to death signal, we performed a molecular modelling with both alleles. Neither TRAIL binding sites in the receptor nor the expression levels of TRAILR-1 in peripheral blood mononuclear cell subsets (monocytes, CD4+ and CD8+ T cells) were modified, suggesting that this SNP may be altering the death signal by some other mechanism. These findings show a role for TRAILR-1 gene variations in the clinical outcome of IFN beta therapy that might have relevance as a biomarker to predict the response to IFN beta in MS. PMID:23658636

  15. A new orphan member of the nuclear hormone receptor superfamily that interacts with a subset of retinoic acid response elements.

    OpenAIRE

    Baes, M.; Gulick, T; Choi, H. S.; Martinoli, M G; Simha, D; Moore, D D

    1994-01-01

    We have identified and characterized a new orphan member of the nuclear hormone receptor superfamily, called MB67, which is predominantly expressed in liver. MB67 binds and transactivates the retinoic acid response elements that control expression of the retinoic acid receptor beta 2 and alcohol dehydrogenase 3 genes, both of which consist of a direct repeat hexamers related to the consensus AGGTCA, separated by 5 bp. MB67 binds these elements as a heterodimer with the 9-cis-retinoic acid rec...

  16. TGF beta-1 dependent fast stimulation of ATM and p53 phosphorylation following exposure to ionizing radiation does not involve TGF beta-receptor I signalling

    NARCIS (Netherlands)

    Wiegman, Erwin M.; Blaese, Marcet A.; Loeffler, Heidi; Coppes, Rob P.; Rodemann, H. Peter

    2007-01-01

    Background and purpose: It has been proposed that radiation induced stimulation of ATM and downstream components involves activation of TGF beta-1 and that this may be due to TGF beta-1-receptor I-Smad signalling. Therefore, the aim of this study was to clarify the distinct role of TGF beta-1-recept

  17. A liver X receptor (LXR)-{beta} alternative splicing variant (LXRBSV) acts as an RNA co-activator of LXR-{beta}

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, Koshi, E-mail: khashi@med.gunma-u.ac.jp [Department of Medicine and Molecular Science, Graduate School of Medicine, Gunma University, Maebashi, Gunma 371-8511 (Japan); Ishida, Emi; Matsumoto, Shunichi; Shibusawa, Nobuyuki; Okada, Shuichi [Department of Medicine and Molecular Science, Graduate School of Medicine, Gunma University, Maebashi, Gunma 371-8511 (Japan); Monden, Tsuyoshi [Department of Endocrinology and Metabolism, Dokkyo Medical College, Mibu, Tochigi (Japan); Satoh, Tetsurou; Yamada, Masanobu; Mori, Masatomo [Department of Medicine and Molecular Science, Graduate School of Medicine, Gunma University, Maebashi, Gunma 371-8511 (Japan)

    2009-12-25

    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)-{beta} LXRBSV has an intronic sequence between exons 2 and 3 in the mouse LXR-{beta} 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-{beta}. 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.

  18. Mouse egg integrin alpha 6 beta 1 functions as a sperm receptor.

    Science.gov (United States)

    Almeida, E A; Huovila, A P; Sutherland, A E; Stephens, L E; Calarco, P G; Shaw, L M; Mercurio, A M; Sonnenberg, A; Primakoff, P; Myles, D G; White, J M

    1995-06-30

    Binding between sperm and egg plasma membranes is an essential step in fertilization. Whereas fertilin, a mammalian sperm surface protein, is involved in this crucial interaction, sperm receptors on the egg plasma membrane have not been identified. Because fertilin contains a predicted integrin ligand domain, we investigated the expression and function of integrin subunits in unfertilized mouse eggs. Polymerase chain reactions detected mRNAs for alpha 5, alpha 6, alpha v, beta 1, beta 3, and beta 5. Immunofluorescence revealed alpha 6 beta 1 and alpha v beta 3 on the plasma membrane. GoH3, a function-blocking anti-alpha 6 monoclonal antibody, abolished sperm binding, but a nonfunction-blocking anti-alpha 6 monoclonal antibody, a function-blocking anti-alpha v beta 3 polyclonal antibody, and an RGD peptide had no effect. Somatic cells bound sperm avidly, but only if they expressed alpha 6 beta 1. A peptide analog of the fertilin integrin ligand domain inhibited sperm binding to eggs and alpha 6 beta 1+ cells and diminished GoH3 staining of eggs. Our results indicate a novel role for the integrin alpha 6 beta 1 as a cell-cell adhesion receptor that mediates sperm-egg binding. PMID:7600577

  19. Structure and diversity of the T cell antigen receptor beta-chain in a teleost fish.

    Science.gov (United States)

    Partula, S; de Guerra, A; Fellah, J S; Charlemagne, J

    1995-07-15

    Cell-mediated immunity (e.g., allograft rejection) is found in all vertebrates, and these reactions are known to depend on thymus-derived cells in amphibian, avian, and mammalian species. The participation of peripheral T cell-like lymphocytes subpopulations to fish immunity is now well documented, but the developmental origin, migration, and peripheral tissue distribution of these cells remain practically unknown. This is mainly due to the difficulty of efficiently thymectomizing fish at an early stage of development and to the lack of Ab strictly specific for thymocytes and T cell surface Ag. One strategy for analyzing T cell biology in fish would be to characterize the genes encoding polypeptides homologous to the TCR molecules. This report describes cDNA clones from the rainbow trout (Oncorhynchus mykiss) that have sequences very similar to amphibian, avian, and mammalian TCR beta-chains. Three complete trout V beta segments belonging to different families were analyzed; one of them had limited amino acid sequence similarity to the human V beta 20 family. The 10 trout beta-chain-joining segments all retain the invariant mammalian J beta residues, and comparison of 66 V beta-J beta junctions led to the identification of a D beta-like sequence (GGACAGGG) that is shorter than but very similar to the chicken D beta and mammalian D beta 1 sequences. There is considerable diversity at the V beta-D beta and D beta-J beta junctions, suggesting the presence of N-nucleotides. The trout C beta extracellular domain is shorter than mammalian C beta, and the hinge region has no cysteine residue. The transmembrane C beta domain contains a lysine residue that in mammals is thought to be involved in charged interactions with members of the CD3 complex. PMID:7608547

  20. Interactions of methoxyacetic acid with androgen receptor

    International Nuclear Information System (INIS)

    Endocrine disruptive compounds (EDC) alter hormone-stimulated, nuclear receptor-dependent physiological and developmental processes by a variety of mechanisms. One recently identified mode of endocrine disruption is through hormone sensitization, where the EDC modulates intracellular signaling pathways that control nuclear receptor function, thereby regulating receptor transcriptional activity indirectly. Methoxyacetic acid (MAA), the primary, active metabolite of the industrial solvent ethylene glycol monomethyl ether and a testicular toxicant, belongs to this EDC class. Modulation of nuclear receptor activity by MAA could contribute to the testicular toxicity associated with MAA exposure. In the present study, we evaluated the impact of MAA on the transcriptional activity of several nuclear receptors including the androgen receptor (AR), which plays a pivotal role in the development and maturation of spermatocytes. AR transcriptional activity is shown to be increased by MAA through a tyrosine kinase signaling pathway that involves PI3-kinase. In a combinatorial setting with AR antagonists, MAA potentiated the AR response without significantly altering the EC50 for androgen responsiveness, partially alleviating the antagonistic effect of the anti-androgens. Finally, MAA treatment of TM3 mouse testicular Leydig cells markedly increased the expression of Cyp17a1 and Shbg while suppressing Igfbp3 expression by ∼ 90%. Deregulation of these genes may alter androgen synthesis and action in a manner that contributes to MAA-induced testicular toxicity.

  1. Glucocorticoid receptor beta increases migration of human bladder cancer cells.

    Science.gov (United States)

    McBeth, Lucien; Nwaneri, Assumpta C; Grabnar, Maria; Demeter, Jonathan; Nestor-Kalinoski, Andrea; Hinds, Terry D

    2016-05-10

    Bladder cancer is observed worldwide having been associated with a host of environmental and lifestyle risk factors. Recent investigations on anti-inflammatory glucocorticoid signaling point to a pathway that may impact bladder cancer. Here we show an inverse effect on the glucocorticoid receptor (GR) isoform signaling that may lead to bladder cancer. We found similar GRα expression levels in the transitional uroepithelial cancer cell lines T24 and UMUC-3. However, the T24 cells showed a significant (p < 0.05) increased expression of GRβ compared to UMUC-3, which also correlated with higher migration rates. Knockdown of GRβ in the T24 cells resulted in a decreased migration rate. Mutational analysis of the 3' untranslated region (UTR) of human GRβ revealed that miR144 might positively regulate expression. Indeed, overexpression of miR144 increased GRβ by 3.8 fold. In addition, miR144 and GRβ were upregulated during migration. We used a peptide nucleic acid conjugated to a cell penetrating-peptide (Sweet-P) to block the binding site for miR144 in the 3'UTR of GRβ. Sweet-P effectively prevented miR144 actions and decreased GRβ expression, as well as the migration of the T24 human bladder cancer cells. Therefore, GRβ may have a significant role in bladder cancer, and possibly serve as a therapeutic target for the disease. PMID:27036026

  2. Immunoanalogue of vertebrate beta-adrenergic receptor in the unicellular eukaryote Paramecium.

    Science.gov (United States)

    Wiejak, Jolanta; Surmacz, Liliana; Wyroba, Elzbieta

    2002-01-01

    Cell fractionation, SDS-PAGE, quantitative Western blot, confocal immunolocalization and immunogold labelling were performed to find an interpretation of the physiological response of the unicellular eukaryote Paramecium to beta-adrenergic ligands. The 69 kDa polypeptide separated by SDS-PAGE in S2 and P2 Paramecium subcellular fractions cross-reacted with antibody directed against human beta2-adrenergic receptor. This was detected by Western blotting followed by chemiluminescent detection. Quantitative image analysis showed that beta-selective adrenergic agonist (-)-isoproterenol--previously shown to enhance phagocytic activity--evoked redistribution of the adrenergic receptor analogue from membraneous (P2) to cytosolic (S2) fraction. The relative increase in immunoreactive band intensity in S2 reached 80% and was paralleled by a 59% decrease in P2 fraction. Confocal immunofluorescence revealed beta2-adrenergic receptor sites on the cell surface and at the ridge of the cytopharynx--where nascent phagosomes are formed. This localization was confirmed by immunoelectron microscopy. These results indicate that the 69 kDa Paramecium polypeptide immunorelated to vertebrate beta2-adrenergic receptor appeared in this evolutionary ancient cell as a nutrient receptor.

  3. Receptor density is key to the alpha2/beta interferon differential activities.

    Science.gov (United States)

    Moraga, Ignacio; Harari, Daniel; Schreiber, Gideon; Uzé, Gilles; Pellegrini, Sandra

    2009-09-01

    Multiple type I interferons (IFN-alpha/beta) elicit Jak/Stat activation, rapid gene induction, and pleiotropic effects, such as differentiation, antiviral protection, and blocks in proliferation, which are dependent on the IFN subtype and the cellular context. To date, ligand- and receptor-specific molecular determinants underlying IFN-alpha/beta differential activities or potencies have been well characterized. To analyze cellular determinants that impact subtype-specific potency, human fibrosarcoma U5A-derived clones, exhibiting a gradient of IFN sensitivity by virtue of increasing receptor levels, were monitored for Jak/Stat signaling, gene induction, cell cycle lengthening, and apoptosis. In cells with scarce receptors, IFN-beta was more potent than IFN-alpha2 in antiproliferative activity, while the two subtypes were equipotent in all other readouts. Conversely, in cells with abundant receptors, IFN-alpha2 matched or even surpassed IFN-beta in all readouts tested. Our results suggest that the differential activities of the IFN subtypes are dictated not only by the intrinsic ligand/receptor binding kinetics but also by the density of cell surface receptor components.

  4. Involvement of tyrosine residues located in the carboxyl tail of the human beta 2-adrenergic receptor in agonist-induced down-regulation of the receptor.

    OpenAIRE

    Valiquette, M; Bonin, H.; Hnatowich, M; Caron, M G; Lefkowitz, R J; Bouvier, M

    1990-01-01

    Chronic exposure of various cell types to adrenergic agonists leads to a decrease in cell surface beta 2-adrenergic receptor (beta 2AR) number. Sequestration of the receptor away from the cell surface as well as a down-regulation of the total number of cellular receptors are believed to contribute to this agonist-mediated regulation of receptor number. However, the molecular mechanisms underlying these phenomena are not well characterized. Recently, tyrosine residues located in the cytoplasmi...

  5. Adrenergic receptors and gastric secretion in dogs. Is a "tonic balance" relationship between vagal and beta 2-adrenergic activity a possibility?

    DEFF Research Database (Denmark)

    Gottrup, F; Hovendal, C; Bech, K;

    1984-01-01

    The relative influence of adrenergic receptors on gastric acid secretion in the dog stomach with different vagal activity or "tone" is almost unknown. beta-adrenoceptors seem to be most important for the direct effect of adrenergic stimulation on acid secretion. In this study the effects of vagot...... that a counterbalance between beta 2-adrenergic and cholinergic vagal tone exists. A "tonic balance theory" is suggested and is probably involved in the resulting acid secretion after vagotomy.......The relative influence of adrenergic receptors on gastric acid secretion in the dog stomach with different vagal activity or "tone" is almost unknown. beta-adrenoceptors seem to be most important for the direct effect of adrenergic stimulation on acid secretion. In this study the effects...... of vagotomy and beta 2-adrenoceptor activity were studied in conscious gastric fistula dogs. Pentagastrin stimulated acid output was increased slightly in non-vagotomized dogs and to its prevagotomy level in vagotomized dogs after propranolol infusion. Practolol showed no such effect. Histamine stimulated...

  6. Effect of Treatment with Different Doses of 17-Beta-Estradiol on Insulin Receptor Substrate-1

    Directory of Open Access Journals (Sweden)

    González C

    2001-07-01

    Full Text Available CONTEXT: Ovarian hormones modulate insulin sensitivity, but their exact role remains unclear. OBJECTIVE: We tried to determine whether different doses of 17-beta-estradiol cause changes in the regulation of insulin receptor substrate (IRS-1 levels, and if so, the possible implications in insulin sensitivity. DESIGN: Ovariectomized rats were treated with different doses of 17-beta-estradiol at 6, 11 and 16 days. MAIN OUTCOME MEASURES: Immunoprecipitation and Western blotting for IRS-1 were performed in different tissues. RESULTS: We found that estradiol treatment has an influence on the amount of IRS-1 but that it acts in different ways depending on the tissue studied, on the length of treatment, and on the doses employed. CONCLUSIONS: Our results suggest that low concentrations of 17-beta-estradiol could be responsible for the upregulation of insulin receptor substrate 1, increasing insulin sensitivity in muscle and adipose tissue. However, insulin receptor substrate 1 is downregulated with high concentrations of 17-beta-estradiol, thus these high hormone plasma levels could favour insulin resistance in peripheral tissues. The role of 17-beta-estradiol seems to modulate insulin receptor substrate 1 levels in insulin dependent tissues, but in a different manner in each tissue. These novel findings are important for improving knowledge about the possible risk for insulin resistance in women taking oral contraceptives or receiving hormone replacement therapy at menopause.

  7. Evolution of retinoic acid receptors and retinoic acid signaling.

    Science.gov (United States)

    Gutierrez-Mazariegos, Juliana; Schubert, Michael; Laudet, Vincent

    2014-01-01

    Retinoic acid (RA) is a vitamin A-derived morphogen controlling important developmental processes in vertebrates, and more generally in chordates, including axial patterning and tissue formation and differentiation. In the embryo, endogenous RA levels are controlled by RA synthesizing and degrading enzymes and the RA signal is transduced by two retinoid receptors: the retinoic acid receptor (RAR) and the retinoid X receptor (RXR). Both RAR and RXR are members of the nuclear receptor superfamily of ligand-activated transcription factors and mainly act as heterodimers to activate the transcription of target genes in the presence of their ligand, all-trans RA. This signaling pathway was long thought to be a chordate innovation, however, recent findings of gene homologs involved in RA signaling in the genomes of a wide variety of non-chordate animals, including ambulacrarians (sea urchins and acorn worms) and lophotrochozoans (annelids and mollusks), challenged this traditional view and suggested that the RA signaling pathway might have a more ancient evolutionary origin than previously thought. In this chapter, we discuss the evolutionary history of the RA signaling pathway, and more particularly of the RARs, which might have experienced independent gene losses and duplications in different animal lineages. In sum, the available data reveal novel insights into the origin of the RA signaling pathway as well as into the evolutionary history of the RARs. PMID:24962881

  8. Discoidin domain receptor 1 is activated independently of beta(1) integrin

    DEFF Research Database (Denmark)

    Vogel, W; Brakebusch, C; Fässler, R;

    2000-01-01

    Various types of collagen have been identified as potential ligands for the two mammalian discoidin domain receptor (DDR) tyrosine kinases, DDR1 and DDR2. It is presently unclear whether collagen-induced DDR receptor activation, which occurs with very slow kinetics, involves additional proteins...... blocking antibodies for alpha(2)beta(1) integrin or in cells with a targeted deletion of the beta(1) integrin gene. Finally, we show that overexpression of dominant negative DDR1 in the myoblast cell line C2C12 blocks cellular differentiation and the formation of myofibers....

  9. PGC-1{beta} regulates mouse carnitine-acylcarnitine translocase through estrogen-related receptor {alpha}

    Energy Technology Data Exchange (ETDEWEB)

    Gacias, Mar; Perez-Marti, Albert; Pujol-Vidal, Magdalena; Marrero, Pedro F. [Department of Biochemistry and Molecular Biology, School of Pharmacy and the Institute of Biomedicine of the University of Barcelona (IBUB) (Spain); Haro, Diego, E-mail: dharo@ub.edu [Department of Biochemistry and Molecular Biology, School of Pharmacy and the Institute of Biomedicine of the University of Barcelona (IBUB) (Spain); Relat, Joana [Department of Biochemistry and Molecular Biology, School of Pharmacy and the Institute of Biomedicine of the University of Barcelona (IBUB) (Spain)

    2012-07-13

    Highlights: Black-Right-Pointing-Pointer The Cact gene is induced in mouse skeletal muscle after 24 h of fasting. Black-Right-Pointing-Pointer The Cact gene contains a functional consensus sequence for ERR. Black-Right-Pointing-Pointer This sequence binds ERR{alpha} both in vivo and in vitro. Black-Right-Pointing-Pointer This ERRE is required for the activation of Cact expression by the PGC-1/ERR axis. Black-Right-Pointing-Pointer Our results add Cact as a genuine gene target of these transcriptional regulators. -- Abstract: Carnitine/acylcarnitine translocase (CACT) is a mitochondrial-membrane carrier proteins that mediates the transport of acylcarnitines into the mitochondrial matrix for their oxidation by the mitochondrial fatty acid-oxidation pathway. CACT deficiency causes a variety of pathological conditions, such as hypoketotic hypoglycemia, cardiac arrest, hepatomegaly, hepatic dysfunction and muscle weakness, and it can be fatal in newborns and infants. Here we report that expression of the Cact gene is induced in mouse skeletal muscle after 24 h of fasting. To gain insight into the control of Cact gene expression, we examine the transcriptional regulation of the mouse Cact gene. We show that the 5 Prime -flanking region of this gene is transcriptionally active and contains a consensus sequence for the estrogen-related receptor (ERR), a member of the nuclear receptor family of transcription factors. This sequence binds ERR{alpha}in vivo and in vitro and is required for the activation of Cact expression by the peroxisome proliferator-activated receptor gamma coactivator (PGC)-1/ERR axis. We also demonstrate that XTC790, the inverse agonist of ERR{alpha}, specifically blocks Cact activation by PGC-1{beta} in C2C12 cells.

  10. Fatty acids activate a chimera of the clofibric acid-activated receptor and the glucocorticoid receptor.

    OpenAIRE

    Göttlicher, M; Widmark, E; Q. Li; Gustafsson, J.A.

    1992-01-01

    Peroxisome proliferators such as clofibric acid, nafenopin, and WY-14,643 have been shown to activate PPAR (peroxisome proliferator-activated receptor), a member of the steroid nuclear receptor superfamily. We have cloned the cDNA from the rat that is homologous to that from the mouse [Issemann, I. & Green, S. (1990) Nature (London) 347, 645-650], which encodes a 97% similar protein with a particularly well-conserved putative ligand-binding domain. To search for physiologically occurring acti...

  11. Dynamic expression of alpha 1 beta 1 and alpha 2 beta 1 integrin receptors by human vascular smooth muscle cells. Alpha 2 beta 1 integrin is required for chemotaxis across type I collagen-coated membranes.

    OpenAIRE

    Skinner, M P; Raines, E W; Ross, R.

    1994-01-01

    Vascular smooth muscle cells (SMCs) in the media of normal arteries express alpha 1 beta 1 integrin with no detectable alpha 2 beta 1 as determined by immunocytochemistry. In contrast, immunoprecipitation of integrins expressed by human SMCs cultured from medial explants shows strong expression of alpha 2 beta 1 and no expression of alpha 1 beta 1. The apparent reciprocal expression of these two collagen and laminin receptors was confirmed by flow cytometric analysis of fluorescent labeled ce...

  12. Ischemia- and agonist-induced changes in. alpha. - and. beta. -adrenergic receptor traffic in guinea pig hearts

    Energy Technology Data Exchange (ETDEWEB)

    Maisel, A.S.; Motulsky, H.J.; Ziegler, M.G.; Insel, P.A. (Univ. of California, La Jolla (USA))

    1987-11-01

    The authors have used radioligand binding techniques and subcellular fraction to assess whether changes in expression of myocardial {alpha}{sub 1}- and {beta}-adrenergic receptors are mediated by a redistribution of receptors between various membrane fractions. Three fractions were prepared from the left ventricles of guinea pigs that underwent either 1 h of ischemia or injection of epinephrine a crude membrane, a purified sarcolemma, and a light vesicle fraction. In control animals {alpha}{sub 1}-adrenergic receptors (({sup 3}H)prazosin binding) in light vesicles was only 25% of the total {alpha}{sub 1}-receptor density found in sarcolemmal and light vesicle fractions as compared with 50% for {beta}-adrenergic receptors (({sup 125}I)iodocyanopindolol binding sites). Although ischemia was associated with a 53% decrease in the number of light vesicle {beta}-adrenergic receptors and a 42% increase in the number of sarcolemma {beta}-receptors there was no change in the number of light vesicle {alpha}{sub 1}-receptors, even though the number of sarcolemmal {alpha}{sub 1}-receptors increased 34%. Epinephrine treatment promoted internalization of {beta}-adrenergic receptors. These results indicate that {alpha}{sub 1} and {beta}{sub 1}-adrenergic receptors may undergo a different cellular itinerary in guinea pig myocardium. Agonist and ischemia-induced changes in surface {beta}-receptors, but not {alpha}{sub 1}-receptors, appear to result from entry and exit of receptors from an intracellular pool that can be isolated in a light vesicle fraction. Changes in expression of {alpha}{sub 1}-adrenergic receptors may represent changes in the properties of receptors found in the sarcolemma or in a membrane fraction other than the light vesicle fraction that they have isolated.

  13. Cardiac beta-receptors in experimental Chagas' disease Receptores beta cardíacos na doença de Chagas experimental

    Directory of Open Access Journals (Sweden)

    Julio E. Enders

    1995-02-01

    Full Text Available Experimental Chagas' disease (45 to 90 days post-infection showed serious cardiac alterations in the contractility and in the pharmacological response to beta adrenergic receptors in normal and T. cruzi infected mice (post-acute phase. Chagasic infection did not change the beta receptors density (78.591 ± 3.125 fmol/mg protein and 73.647 ± 2.194 fmol/mg protein for controls but their affinity was significantly diminished (Kd = 7.299 ± 0.426 nM and Kd = 3.759 ± 0.212 nM for the control p Estudaram-se os receptores beta cardíacos de camundongos infectados pelo Trypanosoma cruzi na fase pós-aguda da doença de Chagas para estabelecer em que medida os mesmos contribuem a gerar respostas anômalas às catecolaminas observadas nestes miocardios. Utilizara-se 3-H/DHA para a marcação dos receptores beta cardíacos dos camundongos normais e dos infectados na fase pós-aguda (45 a 90 dias pós-infecção. O número dos sítios de fixação foi similar nos dois grupos, 78.591 ± 3.125 fmol/mg. Proteína nos chagásicos e 73.647 ± 2.194 fmol/mg. Proteína no grupo controle. Em vez disso, a afinidade verificou-se significativamente diminuida no grupo chagásico (Kd = 7.299 ± 0.426 nM respeito do controle (Kd = 3.759 ± 0.212 nM p < 0.001. Os resultados obtidos demonstram que as modificações observadas na estimulação adrenérgica do miocárdio chagásico se correlacionam com a menor afinidade dos receptores beta cardíacos e que estas alterações exerceriam uma parte determinante para as consequências funcionais que são detectadas na fase crônica.

  14. NMR study of the preparation of 6 {alpha}, 7 {beta}-dihydroxyvouacapan-17 beta-oic acid mannich base derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Flavio Jose Leite dos; Pilo-Veloso, Dorila [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte (Brazil). Inst. de Ciencias Exatas. Dept. Quimica]. E-mail: dorila@zeus.qui.ufmg.br; Ferreira-Alves, Dalton L. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte (Brazil). Inst. de Ciencias Biologicas. Dept. de Farmacologia

    2007-07-01

    This work presents four new Mannich base compounds obtained by the Mannich reaction of a {delta}-keto-lactone derivative of 6{alpha}, 7{beta}-dihydroxyvouacapan- 17{beta}-oic acid, a furano diterpene isolated from the hexane extract of Pterodon polygalaeflorus Benth fruits, which shows anti-inflammatory and analgesic activities. The use of 1D and 2D NMR (COSY, DEPT-135, HMBC, HMQC) spectroscopy made it possible to characterize the new compounds. (author)

  15. [Effect of synthetic cyclopentane beta,beta'-triketones on amino acid metabolism in roots of buckwheat (Fagopyrum esculentum Moench.) seedlings].

    Science.gov (United States)

    Demina, E A; Tishchenko, L Ia; Shestak, O P; Novikov, V L; Anisimov, M M

    2009-01-01

    Germination of buckwheat seeds in solutions of synthetic mono- and tricyclic cyclopentane-containing beta,beta'-triketones of various concentrations was accompanied by inhibition of seedling root growth and changes in the contents of glutamate, gamma-aminobutyric acid, proline, glutamine, and alanine. The monocyclic triketone also affected the amount of isoleucine. It is likely that the increase in proline content is a nonspecific response significant for enhancing stress tolerance in seedlings.

  16. Age-associated alterations in hepatic. beta. -adrenergic receptor/adenylate cyclase complex

    Energy Technology Data Exchange (ETDEWEB)

    Graham, S.M.; Herring, P.A.; Arinze, I.J.

    1987-09-01

    The effect of age on catecholamine regulation of hepatic glycogenolysis and on hepatic adenylate cyclase was studied in male rats up to 24 mo of age. Epinephrine and norepinephrine stimulated glycogenolysis in isolated hepatocytes at all age groups studied. Isoproterenol, however, stimulated glycogenolysis only at 24 mo. In isolated liver membranes, usual activators of adenylate cyclase increased the activity of the enzyme considerably more in membranes from 24-mo-old rats than in membranes from either 3- or 22-mo-old rats. The Mn/sup 2 +/-dependent activity of the cyclase was increased by 2.9-fold in 3-mo-old animals and approx. 5.7-fold in 24-mo-old rats, indicating a substantial age-dependent increase in the intrinsic activity of the catalytic unit. The density of the ..beta..-adrenergic receptor, as measured by the binding of (/sup 125/I)-iodocyanopindolol to plasma membranes, was 5-8 fmol/mg protein in rats aged 3-12 mo but increased to 19 fmol/mg protein in 24-mo-old rats. Computer-aided analysis of isoproterenol competition of the binding indicated a small age-dependent increase in the proportion of ..beta..-receptors in the high-affinity state. These observations suggest that ..beta..-receptor-mediated hepatic glycogenolysis in the aged rat is predicated upon increases in the density of ..beta..-receptors as well as increased intrinsic activity of the catalytic unit of adenylate cyclase.

  17. Glucagon-like peptide-1 receptor agonist treatment reduces beta cell mass in normoglycaemic mice

    NARCIS (Netherlands)

    Ellenbroek, J.H.; Tons, H.A.; Westerouen van Meeteren, M.J.; de Graaf, N.; Hanegraaf, M.A.; Rabelink, T.J.; Carlotti, F.; de Koning, E.J.

    2013-01-01

    AIMS/HYPOTHESIS: Incretin-based therapies improve glycaemic control in patients with type 2 diabetes. In animal models of diabetes, glucagon-like peptide-1 receptor agonists (GLP-1RAs) increase beta cell mass. GLP-1RAs are also evaluated in non-diabetic individuals with obesity and cardiovascular di

  18. Estrogen receptor beta rs1271572 polymorphism and invasive ovarian carcinoma risk

    DEFF Research Database (Denmark)

    Lurie, Galina; Wilkens, Lynne R; Thompson, Pamela J;

    2011-01-01

    The association of ovarian carcinoma risk with the polymorphism rs1271572 in the estrogen receptor beta (ESR2) gene was examined in 4946 women with primary invasive ovarian carcinoma and 6582 controls in a pooled analysis of ten case-control studies within the Ovarian Cancer Association Consortium...

  19. Thyroid Hormone Receptor beta Mediates Acute Illness-Induced Alterations in Central Thyroid Hormone Metabolism

    NARCIS (Netherlands)

    A. Boelen; J. Kwakkel; O. Chassande; E. Fliers

    2009-01-01

    Acute illness in mice profoundly affects thyroid hormone metabolism in the hypothalamus and pituitary gland. It remains unknown whether the thyroid hormone receptor (TR)-beta is involved in these changes. In the present study, we investigated central thyroid hormone metabolism during lipopolysacchar

  20. Fipronil-based photoaffinity probe for Drosophila and human beta 3 GABA receptors.

    Science.gov (United States)

    Sirisoma, N S; Ratra, G S; Tomizawa, M; Casida, J E

    2001-11-19

    Modification of the major insecticide fipronil (1) by replacing three pyrazole substituents (hydrogen for both cyano and amino and trifluoromethyldiazirinyl for trifluoromethylsulfinyl) gives a candidate photoaffinity probe (3) of high potency (IC(50) 2-28 nM) in blocking the chloride channel of Drosophila and human beta 3 GABA receptors.

  1. Metabolic consequences of beta-adrenergic receptor blockade for the acutely ischemic dog myocardium

    Energy Technology Data Exchange (ETDEWEB)

    Westera, G.; Hollander, W. den; Wall, E.E. van der; Eenige, M.J. van; Scholtalbers, S.; Visser, F.C.; Roos, J.P.

    1984-02-01

    In an experimental study in 50 dogs the myocardial uptake of free fatty acids (FFAs) after beta-blockade was determined using radioiodinated heptadecanoic acid as a metabolic tracer. All 4 beta-blockers used (metoprolol, timolol, propranolol and pindolol) lowered the uptake of FFAs in the normal canine heart. Uptake of FFAs was also diminished after coronary artery occlusion per se, but administration of beta-blockers exerted little additional influence on the uptake of FFAs. This observation was qualitatively parallelled by the uptake of /sup 201/Tl in concomitant experiments. Plasma FFA levels were increased by pindolol (non-selective with intrinsic sympathomimetic activity), not changed by metoprolol (a cardioselective betablocking agent) and lowered by timolol and propranolol (both non-selective compounds). The extent of ischemic tissue, as reflected by uptake of iodoheptadecanoic acid and /sup 201/Tl, was diminished by metoprolol but not by other beta-blockers. Regional distribution of both tracers, as shown in the endo-epicardial uptake ratios, was hardly influenced by beta-blockade, except for a small increase of /sup 201/Tl uptake in non-occluded endocardium. Uptake of /sup 201/Tl as well as of iodoheptadecanoic acid in the ischemic area was increased by metoprolol, timolol and propranolol and decreased by pindolol. We conclude that beta-blocking agents confer different effects on myocardial uptake and metabolism of FFAs which might possibly be related to their different inherent properties.

  2. Beta-Adrenergic Receptors and Isoproterenol-stimulated Potassium Transport in Erythrocytes from Normal and Hypothyroid Turkeys: QUANTITATIVE RELATION BETWEEN RECEPTOR OCCUPANCY AND PHYSIOLOGIC RESPONSIVENESS

    OpenAIRE

    Furukawa, Haruyasu; Loeb, John N.; Bilezikian, John P.

    1980-01-01

    We have previously reported that in hypothyroid turkeys the number of beta-adrenergic receptors in intact erythrocytes is reduced by ∼50% without any changes in the affinity of the receptor for the agonist, isoproterenol. In view of the physiological action of the catecholamines to stimulate bidirectional ion fluxes in these cells, we have now examined the possibility that the decrease in beta receptor number might be associated with concomitant changes in catecholamine-dependent potassium io...

  3. Uptake of neutral alpha- and beta-amino acids by human proximal tubular cells

    DEFF Research Database (Denmark)

    Jessen, H; Røigaard, H; Jacobsen, Christian

    1996-01-01

    relatively low. Nor did L-arginine and L-aspartic acid affect the uptake of beta-alanine into AHKE cells. Comparison with the results obtained for normal (NHKE) and immortalized (IHKE) embryonic cells suggested an unaltered expression of the types of transport carriers for neutral alpha- and beta-amino acids...

  4. Concanavalin a increases beta-adrenergic and glucocorticoid receptors in porcine splenocytes

    International Nuclear Information System (INIS)

    We identified specific glucocorticoid and beta-adrenergic receptors on porcine splenocytes. There are 2000 to 4000 glucocorticoid receptors per cell with a K /SUB D/ of 2 to 4 nM and 1000 beta-adrenergic receptors with a K /SUB D/ of 0.3 to 0.6 nM. When splenocytes were incubated with concanavalin A (Con A), there was an approximate 2-fold increase in both gluococorticoid and beta-adrenergic receptors with no change in binding affinity. Incubation of splenocytes with cortisol as low as 40 nM (13 ng/ml) inhibited proliferation in response to Con A. This inhibitory effect of cortisol was not due to cytotoxic effects of glucocorticoids. At maximal physiologic concentrations (400 nM; 135 ng/ml), cortisol caused reductions in Con A activation of thymocytes and peripheral blood mononuclear cells. When eight wk old pigs were restrained, there was an increase in plasma cortisol, atrophy of thymus and reduction in skin test responses to phytohemagglutinin. On the basis of the data, we suggest that physiologic concentrations of stress asociated hormones affect functional activities of porcine lymphoid cells. Since activated splenocytes display increased numbers of receptors for these hormones, perhaps glucocorticoids or catecholamines normally function in vivo to suppress clonal expansion of antigen activated and autoreactive T lymphocytes

  5. Repression of estrogen receptor {beta} function by putative tumor suppressor DBC1

    Energy Technology Data Exchange (ETDEWEB)

    Koyama, Satoshi [Department of Obstetrics and Gynecology, Graduate School of Medicine, The University of Tokyo, Hongo 7-3-1 Bunkyo-ku, Tokyo 113-8655 (Japan); Wada-Hiraike, Osamu, E-mail: osamuwh-tky@umin.ac.jp [Department of Obstetrics and Gynecology, Graduate School of Medicine, The University of Tokyo, Hongo 7-3-1 Bunkyo-ku, Tokyo 113-8655 (Japan); Nakagawa, Shunsuke; Tanikawa, Michihiro; Hiraike, Haruko; Miyamoto, Yuichiro; Sone, Kenbun; Oda, Katsutoshi [Department of Obstetrics and Gynecology, Graduate School of Medicine, The University of Tokyo, Hongo 7-3-1 Bunkyo-ku, Tokyo 113-8655 (Japan); Fukuhara, Hiroshi [Department of Urology, Graduate School of Medicine, The University of Tokyo, Hongo 7-3-1 Bunkyo-ku, Tokyo 113-8655 (Japan); Nakagawa, Keiichi [Department of Radiology, Graduate School of Medicine, The University of Tokyo, Hongo 7-3-1 Bunkyo-ku, Tokyo 113-8655 (Japan); Kato, Shigeaki [SORST, Japan Science and Technology, Honcho 4-1-8, Kawaguchi, Saitama 332-0012 (Japan); Institute of Molecular and Cellular Biosciences, The University of Tokyo, Yayoi 1-1-1 Bunkyo-ku, Tokyo 113-0034 (Japan); Yano, Tetsu; Taketani, Yuji [Department of Obstetrics and Gynecology, Graduate School of Medicine, The University of Tokyo, Hongo 7-3-1 Bunkyo-ku, Tokyo 113-8655 (Japan)

    2010-02-12

    It has been well established that estrogen is involved in the pathophysiology of breast cancer. Estrogen receptor (ER) {alpha} appears to promote the proliferation of cancer tissues, while ER{beta} can protect against the mitogenic effect of estrogen in breast tissue. The expression status of ER{alpha} and ER{beta} may greatly influence on the development, treatment, and prognosis of breast cancer. Previous studies have indicated that the deleted in breast cancer 1 (DBC1/KIAA1967) gene product has roles in regulating functions of nuclear receptors. The gene encoding DBC1 is a candidate for tumor suppressor identified by genetic search for breast cancer. Caspase-dependent processing of DBC1 promotes apoptosis, and depletion of the endogenous DBC1 negatively regulates p53-dependent apoptosis through its specific inhibition of SIRT1. In addition, DBC1 modulates ER{alpha} expression and promotes breast cancer cell survival by binding to ER{alpha}. Here we report an ER{beta}-specific repressive function of DBC1. Immunoprecipitation and immunofluorescence studies show that ER{beta} and DBC1 interact in a ligand-independent manner similar to ER{alpha}. In vitro pull-down assays revealed a direct interaction between DBC1 amino-terminus and activation function-1/2 domain of ER{beta}. Although DBC1 shows no influence on the ligand-dependent transcriptional activation function of ER{alpha}, the expression of DBC1 negatively regulates the ligand-dependent transcriptional activation function of ER{beta}in vivo, and RNA interference-mediated depletion of DBC1 stimulates the transactivation function of ER{beta}. These results implicate the principal role of DBC1 in regulating ER{beta}-dependent gene expressions.

  6. Fatty acid binding receptors in intestinal physiology and pathophysiology

    OpenAIRE

    Kaemmerer, Elke; Plum, Patrick; Klaus, Christina; Weiskirchen, Ralf; Liedtke, Christian; Adolf, Maximilian; Schippers, Angela; Wagner, Norbert; Reinartz, Andrea; Gassler, Nikolaus

    2010-01-01

    Free fatty acids are essential dietary components and recognized as important molecules in the maintenance of cellular homeostasis. In the last decade, the molecular pathways for free fatty acid sensing in the gastrointestinal tract have been further elucidated by molecular identification and functional characterization of fatty acid binding receptors. These sensing molecules belong to the family of G protein-coupled receptors. In the intestine, four important receptors have been described so...

  7. Beta-adrenergic receptor sensitivity, autonomic balance and serotonergic activity in practitioners of Transcendental Meditation

    Energy Technology Data Exchange (ETDEWEB)

    Hill, D.A.

    1989-01-01

    The aim of this thesis was to investigate the acute autonomic effects of the Transcendental Meditation Program (TM) and resolve the conflict arising from discrepant neurochemical and psychophysiological data. Three experimental investigations were performed. The first examined beta{sub 2}-adrenergic receptors (AR's) on peripheral blood lymphocytes, via (I{sup 125})iodocyanopindolol binding, in 10 male mediating and 10 age matched non-meditating control subjects, to test the hypothesis that the long-term practice of TM and the TM Sidhi Program (TMSP) reduces end organ sensitivity to adrenergic agonists. The second investigated respiratory sinus arrhythmia (an indirect measure of cardiac Parasympathetic Nervous System tone), and skin resistance (a measure of Sympathetic Nervous System tone) during periods of spontaneous respiratory apneusis, a phenomenon occurring during TM that is known to mark the subjective experience of transcending. The third was within subject investigation of the acute effects of the TMSP on 5-hydroxytryptamine (5-HT) activity. Platelet 5-HT was assayed by high pressure liquid chromatography with electrochemical detection, plasma prolactin (PL) and lutenizing hormone (LH) by radioimmunoassay, tryptophan by spectrofluorimetry, and alpha-1-acid glycoprotein (AGP, a modulator of 5-HT uptake) by radial immunodiffusion assay.

  8. Role of sialic acid for platelet life span: exposure of beta-galactose results in the rapid clearance of platelets from the circulation by asialoglycoprotein receptor-expressing liver macrophages and hepatocytes

    DEFF Research Database (Denmark)

    Sørensen, Anne Louise; Rumjantseva, Viktoria; Nayeb-Hashemi, Sara;

    2009-01-01

    Although surface sialic acid is considered a key determinant for the survival of circulating blood cells and glycoproteins, its role in platelet circulation lifetime is not fully clarified. We show that thrombocytopenia in mice deficient in the St3gal4 sialyltransferase gene (St3Gal-IV(-/-) mice)...

  9. Preparation and spectral investigation of inclusion complex of caffeic acid with hydroxypropyl-beta-cyclodextrin.

    Science.gov (United States)

    Zhang, Min; Li, Jinxia; Zhang, Liwei; Chao, Jianbin

    2009-01-01

    The inclusion complexation behavior of caffeic acid (CA) with hydroxypropyl-beta-cyclodextrin (HP-beta-CD) was studied by UV-vis, fluorescence spectroscopy and nuclear magnetic resonance spectroscopy (NMR). Experimental conditions including the concentration of HP-beta-CD and media acidity were investigated in detail. The result suggested HP-beta-CD was more suitable for including CA in acidity solution. The binding contants (K) of the inclusion complexes were determined by linear regression analysis and the inclusion ratio was found to be 1:1. The water solubility of CA was increased by inclusion with HP-beta-CD according to the phase-solubility diagram. The spatial configuration of complex has been proposed based on (1)H NMR and two-dimensional (2D) NMR, the result suggested that CA was entrapped inside the hydrophobic core of HP-beta-CD with the lipophilic aromatic ring and the portion of ethylene.

  10. Effect of extracellular pH on recombinant alpha1beta2gamma2 and alpha1beta2 GABAA receptors.

    Science.gov (United States)

    Mercik, Katarzyna; Pytel, Maria; Cherubini, Enrico; Mozrzymas, Jerzy W

    2006-08-01

    Recently, we have reported that extracellular protons allosterically modulated neuronal GABA(A) receptors [Mozrzymas, J.W., Zarnowska, E.D., Pytel, M., Mercik, K., 2003a. Modulation of GABA(A) receptors by hydrogen ions reveals synaptic GABA transient and a crucial role of desensitiztion process. Journal of Neuroscience 23, 7981-7992]. However, GABAARs in neurons are heterogeneous and the effect of hydrogen ions depends on the receptor subtype. In particular, gamma2 subunit sets the receptor sensibility to several modulators including protons. However, the mechanisms whereby protons modulate gamma2-containing and gamma2-free GABAARs have not been fully elucidated. To this end, current responses to ultrafast GABA applications were recorded for alpha1beta2gamma2 and alpha1beta2 receptors at different pH values. For both receptor types, increase in pH induced a decrease in amplitudes of currents elicited by saturating [GABA] but this effect was stronger for alpha1beta2 receptors. In the case of alpha1beta2gamma2 receptors, protons strongly affected the current time course due to a down regulation of binding and desensitization rates. This effect was qualitatively similar to that described in neurons. Protons strongly influenced the amplitude of alpha1beta2 receptor-mediated currents but the effect on their kinetics was weak suggesting a predominant direct non-competitive inhibition with a minor allosteric modulation. In conclusion, we provide evidence that extracellular protons strongly affect GABAA receptors and that, depending on the presence of the gamma2 subunit, the modulatory mechanisms show profound quantitative and qualitative differences.

  11. A role for the androgen metabolite, 5alpha-androstane-3beta,17beta-diol, in modulating oestrogen receptor beta-mediated regulation of hormonal stress reactivity.

    Science.gov (United States)

    Handa, R J; Weiser, M J; Zuloaga, D G

    2009-03-01

    Activation of the hypothalamic-pituitary-adrenal (HPA) axis is a basic response of animals to environmental perturbations that threaten homeostasis. These responses are regulated by neurones in the paraventricular nucleus of the hypothalamus (PVN) that synthesise and secrete corticotrophin-releasing hormone (CRH). Other PVN neuropeptides, such as arginine vasopressin and oxytocin, can also modulate activity of CRH neurones in the PVN and enhance CRH secretagogue activity of the anterior pituitary gland. In rodents, sex differences in HPA reactivity are well established; females exhibit a more robust activation of the HPA axis after stress than do males. These sex differences primarily result from opposing actions of sex steroids, testosterone and oestrogen, on HPA function. Ostreogen enhances stress activated adrenocorticotrophic hormone (ACTH) and corticosterone (CORT) secretion, whereas testosterone decreases the gain of the HPA axis and inhibits ACTH and CORT responses to stress. Data show that androgens can act directly on PVN neurones in the male rat through a novel pathway involving oestrogen receptor (ER)beta, whereas oestrogen acts predominantly through ERalpha. Thus, we examined the hypothesis that, in males, testosterone suppresses HPA function via an androgen metabolite that binds ERbeta. Clues to the neurobiological mechanisms underlying such a novel action can be gleaned from studies showing extensive colocalisation of ERbeta in oxytocin-containing cells of the PVN. Hence, in this review, we address the possibility that testosterone inhibits HPA reactivity by metabolising to 5alpha-androstane-3beta,17beta-diol, a compound that binds ERbeta and regulates oxytocin containing neurones of the PVN. These findings suggest a re-evaluation of studies examining pathways for androgen receptor signalling. PMID:19207807

  12. Ligand-dependent inhibition of beta-catenin/TCF signaling by androgen receptor.

    Science.gov (United States)

    Chesire, Dennis R; Isaacs, William B

    2002-12-01

    Beta-catenin signaling may contribute to prostate cancer (CaP) progression. Although beta-catenin is known to upregulate T cell factor (TCF) target gene expression in CaP cells, recent evidence demonstrates its capacity to enhance ligand-dependent androgen receptor (AR) function. Thus, we wished to further understand the interaction between these two pathways. We find in both CaP cells (CWR22-Rv1, LAPC-4, DU145) and non-CaP cells (HEK-293, TSU, SW480, HCT-116) that beta-catenin/TCF-related transcription (CRT), as measured by activation of a synthetic promoter and that of cyclin D1, is inhibited by androgen treatment. This inhibition is AR-dependent, as it only occurs in cells expressing AR endogenously or transiently, and is abrogated by AR antagonists. Additional analyses convey that the ligand-dependent nature of CRT suppression depends on transactivation-competent AR in the nucleus, but not on indirect effects stemming from AR target gene expression. Given the recent work identifying an AR/beta-catenin interaction, and from our finding that liganded AR does not prompt gross changes in the constitutive nuclear localization of TCF4 or mutant beta-catenin, we hypothesized that transcription factor (i.e. AR and TCF) competition for beta-catenin recruitment may explain, in part, androgen-induced suppression of CRT. To address this idea, we expressed an AR mutant lacking its DNA-binding domain (DBD). This receptor could not orchestrate ligand-dependent CRT repression, thereby providing support for those recent data implicating the AR DBD/LBD as necessary for beta-catenin interaction. Further supporting this hypothesis, TCF/LEF over-expression counteracts androgen-induced suppression of CRT, and requires beta-catenin binding activity to do so. Interestingly, TCF4 over-expression potently antagonizes AR function; however, this inhibition may occur independently of beta-catenin/TCF4 interaction. These results from TCF4 over-expression analyses, taken together, provide

  13. Pancreatic Beta Cell G-Protein Coupled Receptors and Second Messenger Interactions: A Systems Biology Computational Analysis.

    Science.gov (United States)

    Fridlyand, Leonid E; Philipson, Louis H

    2016-01-01

    Insulin secretory in pancreatic beta-cells responses to nutrient stimuli and hormonal modulators include multiple messengers and signaling pathways with complex interdependencies. Here we present a computational model that incorporates recent data on glucose metabolism, plasma membrane potential, G-protein-coupled-receptors (GPCR), cytoplasmic and endoplasmic reticulum calcium dynamics, cAMP and phospholipase C pathways that regulate interactions between second messengers in pancreatic beta-cells. The values of key model parameters were inferred from published experimental data. The model gives a reasonable fit to important aspects of experimentally measured metabolic and second messenger concentrations and provides a framework for analyzing the role of metabolic, hormones and neurotransmitters changes on insulin secretion. Our analysis of the dynamic data provides support for the hypothesis that activation of Ca2+-dependent adenylyl cyclases play a critical role in modulating the effects of glucagon-like peptide 1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP) and catecholamines. The regulatory properties of adenylyl cyclase isoforms determine fluctuations in cytoplasmic cAMP concentration and reveal a synergistic action of glucose, GLP-1 and GIP on insulin secretion. On the other hand, the regulatory properties of phospholipase C isoforms determine the interaction of glucose, acetylcholine and free fatty acids (FFA) (that act through the FFA receptors) on insulin secretion. We found that a combination of GPCR agonists activating different messenger pathways can stimulate insulin secretion more effectively than a combination of GPCR agonists for a single pathway. This analysis also suggests that the activators of GLP-1, GIP and FFA receptors may have a relatively low risk of hypoglycemia in fasting conditions whereas an activator of muscarinic receptors can increase this risk. This computational analysis demonstrates that study of second messenger

  14. Practical synthesis of enantiomerically pure beta2-amino acids via proline-catalyzed diastereoselective aminomethylation of aldehydes.

    Science.gov (United States)

    Chi, Yonggui; English, Emily P; Pomerantz, William C; Horne, W Seth; Joyce, Leo A; Alexander, Lane R; Fleming, William S; Hopkins, Elizabeth A; Gellman, Samuel H

    2007-05-01

    Proline-catalyzed diastereoselective aminomethylation of aldehydes using a chiral iminium ion, generated from a readily prepared precursor, provides alpha-substituted-beta-amino aldehydes with 85:15 to 90:10 dr. The alpha-substituted-beta-amino aldehydes can be reduced to beta-substituted-gamma-amino alcohols, the major diastereomer of which can be isolated via crystallization or column chromatography. The amino alcohols are efficiently transformed to protected beta2-amino acids, which are valuable building blocks for beta-peptides, natural products, and other interesting molecules. Because conditions for the aminomethylation and subsequent reactions are mild, beta2-amino acid derivatives with protected functional groups in the side chain, such as beta2-homoglutamic acid, beta2-homotyrosine, and beta2-homolysine, can be prepared in this way. The synthetic route is short, and purifications are simple; therefore, this method enables the preparation of protected beta2-amino acids in useful quantities.

  15. NK1 receptor fused to beta-arrestin displays a single-component, high-affinity molecular phenotype

    DEFF Research Database (Denmark)

    Martini, Lene; Hastrup, Hanne; Holst, Birgitte;

    2002-01-01

    with low affinity against antagonists. In contrast, in the NK1-beta-arrestin1 fusion protein, all ligands bound with similar affinity independent of the choice of radioligand and with Hill coefficients near unity. We conclude that the NK1 receptor in complex with arrestin is in a high-affinity, stable......Arrestins are cytosolic proteins that, upon stimulation of seven transmembrane (7TM) receptors, terminate signaling by binding to the receptor, displacing the G protein and targeting the receptor to clathrin-coated pits. Fusion of beta-arrestin1 to the C-terminal end of the neurokinin NK1 receptor...... Gq/G11 and Gs pathways. The NK1-beta-arrestin1 fusion construct bound nonpeptide antagonists with increased affinity but surprisingly also bound two types of agonists, substance P and neurokinin A, with high, normal affinity. In the wild-type NK1 receptor, neurokinin A (NKA) competes for binding...

  16. Promiscuous Seven Transmembrane Receptors Sensing L-α-amino Acids

    DEFF Research Database (Denmark)

    Smajilovic, Sanela; Wellendorph, Petrine; Bräuner-Osborne, Hans

    2014-01-01

    A number of nutrient sensing seven trans-membrane (7TM) receptors have been identified and characterized over the past few years. While the sensing mechanisms to carbohydrates and free fatty acids are well understood, the molecular basis of amino acid sensing has recently come to the limelight. T....... The present review describes the current status of promiscuous L-α-amino acid sensors, the calcium sensing receptor (CaSR), the GPRC6A receptor, the T1R1/T1R3 receptor and also their molecular pharmacology, expression pattern and physiological significance.......A number of nutrient sensing seven trans-membrane (7TM) receptors have been identified and characterized over the past few years. While the sensing mechanisms to carbohydrates and free fatty acids are well understood, the molecular basis of amino acid sensing has recently come to the limelight...

  17. Synthesis of L-[{beta}-{sup 11}C]amino acids using immobilized enzymes

    Energy Technology Data Exchange (ETDEWEB)

    Ikemoto, M.; Yada, T. [Ikeda Food Research Corporation, Minooki-cho, Fukuyama-shi, Hiroshima (Japan); Sasaki, M. [Sumitomo Heavy Industries, Kitashinagawa, Shinagawa-ku, Tokyo (Japan); Haradahira, T. [Division of Advanced Technology for Medical Imaging, National Institute of Radiological Sciences, Chiba (Japan); Omura, H.; Furuya, Y.; Watanabe, Y.; Suzuki, K. [Subfemtomole Biorecognition Project, Japan Science and Technology Corporation, Osaka (Japan)

    1999-04-01

    L-[{beta}-{sup 11}C]-3,4-dihydroxyphenylalanine(L-[{beta}-{sup 11}C]DOPA) and L-[{beta}-{sup 11}C]-5-hydroxytryptophan(L-[{beta}-{sup 11}C]-5-HTP) were synthesized in one step with immobilized thermostable enzymes (alanine racemase, D-amino acid oxidase, and {beta}-tyrosinase or tryptophanase) on an aminopropyl-CPG carrier in a single column and by passing D,L-[3-{sup 11}C]alanine through the column with coenzymes and other substrates. L-[{beta}-{sup 11}C]DOPA and L-[{beta}-{sup 11}C]-5-HTP could be obtained at yields of 53% and 60%, respectively, by optimizing the amounts and the ratios of the enzymes used, the reaction temperature, the pH, and the flow rate. Moreover, the same immobilized enzyme column could be used repeatedly.

  18. Protein-tyrosine-phosphatase SHPTP2 couples platelet-derived growth factor receptor beta to Ras.

    OpenAIRE

    Bennett, A.M.; Tang, T. L.; SUGIMOTO, S; Walsh, C T; Neel, B G

    1994-01-01

    Protein-tyrosine-phosphatase SHPTP2 (Syp/PTP-1D/PTP2C) is the homologue of the Drosophila corkscrew (csw) gene product, which transmits positive signals from receptor tyrosine kinases. Likewise, SHPTP2 has been implicated in positive signaling from platelet-derived growth factor receptor beta (PDGFR). Upon PDGF stimulation, SHPTP2 binds to the PDGFR and becomes tyrosine-phosphorylated. We have identified tyrosine-542 (pY542TNI) as the major in vivo site of SHPTP2 tyrosine phosphorylation. The...

  19. Chemokine receptor expression on B cells and effect of interferon-beta in multiple sclerosis

    DEFF Research Database (Denmark)

    Sørensen, Torben Lykke; Roed, Hanne; Sellebjerg, Finn

    2002-01-01

    We investigated the B-cell expression of chemokine receptors CXCR3, CXCR5 and CCR5 in the blood and cerebrospinal fluid (CSF) from patients in relapse of multiple sclerosis (MS) and in neurological controls. Chemokine receptor expression was also studied in interferon-beta-treated patients...... with relapsing-remitting or secondary progressive MS. We observed significantly higher expression of CXCR3 on B cells in the CSF in active MS than in controls. Patients with active MS also had higher B-cell expression of CCR5 in blood. No major differences between RRMS and SPMS patients were detected...

  20. Ryanodine receptors are involved in nuclear calcium oscillation in primary pancreatic {beta}-cells

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Ji [Urological Surgery Research Institute, Southwest Hospital, Third Military Medical University, Chongqing (China); National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing (China); Chen, Zheng [National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing (China); Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI (United States); Yin, Wenxuan; Miao, Lin [National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing (China); Zhou, Zhansong, E-mail: Zhouzhansong@sohu.com [Urological Surgery Research Institute, Southwest Hospital, Third Military Medical University, Chongqing (China); Ji, Guangju, E-mail: Gj28@ibp.ac.cn [National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing (China)

    2012-06-29

    Highlights: Black-Right-Pointing-Pointer We found that RyRs are expressed on the nuclear envelope in single primary pancreatic {beta}-cells and isolated nuclei. Black-Right-Pointing-Pointer We showed that the pattern of glucose-induced Ca{sup 2+} oscillation in the nucleus and cytosol was similar. Black-Right-Pointing-Pointer Our results demonstrate that ryanodine-sensitive Ca{sup 2+} stores exist and have function in the pancreatic {beta}-cell nucleus. -- Abstract: Ryanodine receptors (RyRs) are mainly located on the endoplasmic reticulum (ER) and play an important role in regulating glucose-induced cytosolic Ca{sup 2+} oscillation in pancreatic {beta}-cells. However, subcellular locations and functions of RyRs on other cell organelles such as nuclear envelope are not well understood. In order to investigate the role of RyRs in nuclear Ca{sup 2+} oscillation we designed and conducted experiments in intact primary pancreatic {beta}-cells. Immunocytochemistry was used to examine the expression of RYRs on the nuclear envelope. Confocal microscopy was used to evaluate the function of RYRs on the nuclear envelope. We found that RyRs are expressed on the nuclear envelope in single primary pancreatic {beta}-cells and isolated nuclei. Laser scanning confocal microscopy studies indicated that application of glucose to the cells co-incubated with Ca{sup 2+} indicator Fluo-4 AM and cell-permeable nuclear indicator Hoechst 33342 resulted in nuclear Ca{sup 2+} oscillation. The pattern of glucose-induced Ca{sup 2+} oscillation in the nucleus and cytosol was similar. The reduction of Ca{sup 2+} oscillation amplitude by ryanodine was much greater in the nucleus though both the cytosol and the nucleus Ca{sup 2+} amplitude decreased by ryanodine. Our results suggest that functional ryanodine receptors not only exist in endoplasmic reticulum but are also expressed in nuclear envelope of pancreatic {beta}-cells.

  1. Beta-2-Adrenergic Receptor Methylation Influences Asthma Phenotype in The School Inner City Asthma Study

    OpenAIRE

    Gaffin, Jonathan M.; Phipatanakul, Wanda

    2014-01-01

    Asthma is the most common chronic illness of childhood and inner city residents suffer a disproportionately high rate of asthma diagnosis and asthma morbidity. The School Inner City Asthma Study investigates the school classroom based environmental exposures that may lead to asthma morbidity in inner city school children with asthma. Within this cohort, we investigated the role of methylation at the promoter region of the beta-2-adrenergic receptor in relation to asthma morbidity. We found th...

  2. Determination of beta-adrenergic receptor blocking pharmaceuticals in united states wastewater effluent

    Energy Technology Data Exchange (ETDEWEB)

    Huggett, D.B.; Khan, I.A.; Foran, C.M.; Schlenk, D

    2003-02-01

    This is the first report of beta-adrenergic receptor antagonist pharmaceuticals in United States wastewater effluent. - Beta adrenergic receptor antagonists ({beta}-Blockers) are frequently prescribed medications in the United States and have been identified in European municipal wastewater effluent, however no studies to date have investigated these compounds in United States wastewater effluent. Municipal wastewater effluent was collected from treatment facilities in Mississippi, Texas, and New York to investigate the occurrence of metoprolol, nadolol, and propranolol. Propranolol was identified in all wastewater samples analyzed (n=34) at concentrations {<=}1.9 {mu}g/l. Metoprolol and nadolol were identified in {>=}71% of the samples with concentrations of metoprolol {<=}1.2 {mu}g/l and nadolol {<=}0.36 {mu}g/l. Time course studies at both Mississippi plants and the Texas plant indicate that concentrations of propranolol, metoprolol, and nadolol remain relatively constant at each sampling period. This study indicates that {beta}-Blockers are present in United States wastewater effluent in the ng/l to {mu}g/l range.

  3. Pharmacology of bile acid receptors: Evolution of bile acids from simple detergents to complex signaling molecules.

    Science.gov (United States)

    Copple, Bryan L; Li, Tiangang

    2016-02-01

    For many years, bile acids were thought to only function as detergents which solubilize fats and facilitate the uptake of fat-soluble vitamins in the intestine. Many early observations; however, demonstrated that bile acids regulate more complex processes, such as bile acids synthesis and immune cell function through activation of signal transduction pathways. These studies were the first to suggest that receptors may exist for bile acids. Ultimately, seminal studies by many investigators led to the discovery of several bile acid-activated receptors including the farnesoid X receptor, the vitamin D receptor, the pregnane X receptor, TGR5, α5 β1 integrin, and sphingosine-1-phosphate receptor 2. Several of these receptors are expressed outside of the gastrointestinal system, indicating that bile acids may have diverse functions throughout the body. Characterization of the functions of these receptors over the last two decades has identified many important roles for these receptors in regulation of bile acid synthesis, transport, and detoxification; regulation of glucose utilization; regulation of fatty acid synthesis and oxidation; regulation of immune cell function; regulation of energy expenditure; and regulation of neural processes such as gastric motility. Through these many functions, bile acids regulate many aspects of digestion ranging from uptake of essential vitamins to proper utilization of nutrients. Accordingly, within a short time period, bile acids moved beyond simple detergents and into the realm of complex signaling molecules. Because of the important processes that bile acids regulate through activation of receptors, drugs that target these receptors are under development for the treatment of several diseases, including cholestatic liver disease and metabolic syndrome. In this review, we will describe the various bile acid receptors, the signal transduction pathways activated by these receptors, and briefly discuss the physiological processes that

  4. Beta-glucosidases and nucleic acids encoding same

    DEFF Research Database (Denmark)

    2012-01-01

    and pharmaceuticals. Several enzymes of the newly identified strain are efficient in degradation of lignocellulosic biomasses. In particular one enzyme has been identified and characterised as having improved beta-glucosidase activity. The identified beta-glucosidase has improved thermal stability, while maintaining...

  5. beta. -Receptor-mediated increase in cerebral blood flow during hypoglycemia

    Energy Technology Data Exchange (ETDEWEB)

    Hollinger, B.R.; Bryan, R.M. (Pennsylvania State Univ., Hershey (USA))

    1987-10-01

    The authors tested the hypothesis that {beta}-adrenergic receptor stimulation is involved with the increase in regional cerebral blood flow (rCBF) during hypoglycemia. Rats were surgically prepared with the use of halothane-nitrous oxide anesthesia. A plaster restraining cast was placed around the hindquarters, and anesthesia was discontinued. Hypoglycemia was produced by an intravenous injection of insulin; normoglycemic control rates were given saline. Propranolol was administered to some control and some hypoglycemic rats to block the {beta}-adrenergic receptors. Regional CBF was measured using 4-(N-methyl-{sup 14}C)iodoantipyrine. Regional CBF increased during hypoglycemia in rats that were not treated with propranolol. The increase varied from {approximately}60 to 200% depending on the brain region. During hypoglycemia, propranolol abolished the increase in rCBF in the hypothalamus, cerebellum, and pyramidal tract. In other regions the increase in rCBF was only 33-65% of the increase in hypoglycemic rats that were not treated with propranolol. They conclude that {beta}-receptor stimulation plays a major role in the increase in rCBF during hypoglycemia.

  6. Profiling the Changes in Signaling Pathways in Ascorbic Acid/beta-Glycerophosphate-Induced Osteoblastic Differentiation

    NARCIS (Netherlands)

    Chaves Neto, Antonio Hernandes; Queiroz, Karla Cristiana; Milani, Renato; Paredes-Gamero, Edgar Julian; Justo, Giselle Zenker; Peppelenbosch, Maikel P.; Ferreira, Carmen Verissima

    2011-01-01

    Despite numerous reports on the ability of ascorbic acid and beta-glycerophosphate (AA/beta-GP) to induce osteoblast differentiation, little is known about the molecular mechanisms involved in this phenomenon. In this work, we used a peptide array containing specific consensus sequences (potential s

  7. In situ detection of TGF betas, TGF beta receptor Ⅱ mRNA and telomerase activity in rat cholangiocarcinogenesis

    Institute of Scientific and Technical Information of China (English)

    Jian-Ping Lu; Jian-Qun Mao; Ming-Sheng Li; Shi-Lun Lu; Xi-Qi Hu; Shi-Neng Zhu; Shintaro Nomura

    2003-01-01

    AIM: Initial report on the in situ examination of the mRNA expression of transforming growth factor betas (TGFβs),TGFβ type Ⅱ receptor (TβRII) and telomerase activity in the experimental rat liver tissue during cholangiocarcinogenesis.METHODS: Rat liver cholangiocarcinogenesis was induced by 3'-methyl 4-dimethylazobenzene (3'Me-DAB). In situhybridization was used to examine the TGFβs) and TGFβ type Ⅱ receptor (TβRⅡ) mRNA, in situ TRAP was used to check the telomerase activity in the tissue samples.RESULTS: There was no TGFβs, TβRⅡ mRNA expression or telomerase activity in the control rat cholangiocytes. The expression of TGFβ1, TβRⅡ was increased in regenerative,hyperplastic, dysplastic cholangiocytes and cholangiocarcinoma (CC) cells. The expression of TGFβ2 mRNA was observed in only a part of hyperplastic, dysplastic cholangiocytes. TGFβ3expression was very weak, only in hyperplastic lesion. There was positive telomerase activity in the regenerative,hyperplastic, dysplastic cholangiocytes, and CC cells. Stroma fibroblasts of these lesions also showed positive TGFβs, TβRⅡ mRNA expression and telomerase activity.CONCLUSION: There were TGFβs, TβRⅡ expression and telomerase activity in hyperplastic, dysplastic cholangiocytes,cholangiocarcinoma cells as well as in stroma fibroblasts during cholangiocarcinogenesis. Their expression or activity is important in cholangiocarcinogenesis andstroma formation.

  8. Human-Specific SNP in Obesity Genes, Adrenergic Receptor Beta2 (ADRB2), Beta3 (ADRB3), and PPAR γ2 (PPARG), during Primate Evolution

    OpenAIRE

    Takenaka, Akiko; Nakamura, Shin; Mitsunaga, Fusako; Inoue-Murayama, Miho; Udono, Toshifumi; Suryobroto, Bambang

    2012-01-01

    Adrenergic-receptor beta2 (ADRB2) and beta3 (ADRB3) are obesity genes that play a key role in the regulation of energy balance by increasing lipolysis and thermogenesis. The Glu27 allele in ADRB2 and the Arg64 allele in ADRB3 are associated with abdominal obesity and early onset of non-insulin-dependent diabetes mellitus (NIDDM) in many ethnic groups. Peroxisome proliferator-activated receptor γ (PPARG) is required for adipocyte differentiation. Pro12Ala mutation decreases PPARG activity and ...

  9. BGL4 beta-glucosidase and nucleic acids encoding the same

    Science.gov (United States)

    Dunn-Coleman, Nigel [Los Gatos, CA; Goedegebuur, Frits [Vlaardingen, NL; Ward, Michael [San Francisco, CA; Yao, Jian [Sunnyvale, CA

    2008-01-22

    The present invention provides a novel .beta.-glucosidase nucleic acid sequence, designated bgl4, and the corresponding BGL4 amino acid sequence. The invention also provides expression vectors and host cells comprising a nucleic acid sequence encoding BGL4, recombinant BGL4 proteins and methods for producing the same.

  10. BGL6 beta-glucosidase and nucleic acids encoding the same

    Energy Technology Data Exchange (ETDEWEB)

    Dunn-Coleman, Nigel; Ward, Michael

    2015-08-11

    The present invention provides a novel .beta.-glucosidase nucleic acid sequence, designated bgl6, and the corresponding BGL6 amino acid sequence. The invention also provides expression vectors and host cells comprising a nucleic acid sequence encoding BGL6, recombinant BGL6 proteins and methods for producing the same.

  11. BGL4 beta-glucosidase and nucleic acids encoding the same

    Energy Technology Data Exchange (ETDEWEB)

    Dunn-Coleman, Nigel (Los Gatos, CA); Goedegebuur, Frits (Vlaardingen, NL); Ward, Michael (San Francisco, CA); Yao, Jian (Sunnyvale, CA)

    2011-12-06

    The present invention provides a novel .beta.-glucosidase nucleic acid sequence, designated bgl4, and the corresponding BGL4 amino acid sequence. The invention also provides expression vectors and host cells comprising a nucleic acid sequence encoding BGL4, recombinant BGL4 proteins and methods for producing the same.

  12. BGL3 beta-glucosidase and nucleic acids encoding the same

    Energy Technology Data Exchange (ETDEWEB)

    Dunn-Coleman, Nigel (Los Gatos, CA); Goedegebuur, Frits (Vlaardingen, NL); Ward, Michael (San Francisco, CA); Yao, Jian (Sunnyvale, CA)

    2011-06-14

    The present invention provides a novel .beta.-glucosidase nucleic acid sequence, designated bgl3, and the corresponding BGL3 amino acid sequence. The invention also provides expression vectors and host cells comprising a nucleic acid sequence encoding BGL3, recombinant BGL3 proteins and methods for producing the same.

  13. BGL6 beta-glucosidase and nucleic acids encoding the same

    Energy Technology Data Exchange (ETDEWEB)

    Dunn-Coleman, Nigel (Los Gatos, CA); Ward, Michael (San Francisco, CA)

    2009-09-01

    The present invention provides a novel .beta.-glucosidase nucleic acid sequence, designated bgl6, and the corresponding BGL6 amino acid sequence. The invention also provides expression vectors and host cells comprising a nucleic acid sequence encoding BGL6, recombinant BGL6 proteins and methods for producing the same.

  14. BGL7 beta-glucosidase and nucleic acids encoding the same

    Energy Technology Data Exchange (ETDEWEB)

    Dunn-Coleman, Nigel (Los Gatos, CA); Ward, Michael (San Francisco, CA)

    2008-08-05

    The present invention provides a novel .beta.-glucosidase nucleic acid sequence, designated bgl7, and the corresponding BGL7 amino acid sequence. The invention also provides expression vectors and host cells comprising a nucleic acid sequence encoding BGL7, recombinant BGL7 proteins and methods for producing the same.

  15. Food restriction prevents an age-associated increase in rat liver beta-adrenergic receptors

    Energy Technology Data Exchange (ETDEWEB)

    Dax, E.M.; Ingram, D.K.; Partilla, J.S.; Gregerman, R.I.

    1989-05-01

    In male Wistar rats fed ad libitum (24% protein, 4.5 Kcal/gm), the (/sup 125/I)iodopindolol binding capacity of the beta-adrenergic receptors in liver of 24-month-old animals is 3-4 times greater than that of 6-month-old counterparts. In rats fed the same diet, on alternate days from weaning, the receptor capacity did not increase significantly between 6 and 24 months (10.20 +/- 0.55 vs 9.20 +/- 0.72 fmol/mg) or between 24 and 30 months. This was not due to acute dietary deprivation, as rats food-restricted for only 2 weeks, at 23.5 months of age, also showed elevated receptor capacities compared to 6-month-old ad libitum fed animals. Moreover, intermittent feeding produced no significant effects among 6-month-old animals, whether restricted since weaning or for two weeks prior to sacrifice. Many biochemical parameters that decrease with aging in rats fed ad libitum are prevented by dietary restriction. Our results demonstrate that a reproducible biochemical process that increases with aging is also prevented with dietary restriction. The age-related, liver beta-receptor increase may be a potentially reliable marker for studying biochemical perturbations that modify life span.

  16. Food restriction prevents an age-associated increase in rat liver beta-adrenergic receptors

    International Nuclear Information System (INIS)

    In male Wistar rats fed ad libitum (24% protein, 4.5 Kcal/gm), the [125I]iodopindolol binding capacity of the beta-adrenergic receptors in liver of 24-month-old animals is 3-4 times greater than that of 6-month-old counterparts. In rats fed the same diet, on alternate days from weaning, the receptor capacity did not increase significantly between 6 and 24 months (10.20 +/- 0.55 vs 9.20 +/- 0.72 fmol/mg) or between 24 and 30 months. This was not due to acute dietary deprivation, as rats food-restricted for only 2 weeks, at 23.5 months of age, also showed elevated receptor capacities compared to 6-month-old ad libitum fed animals. Moreover, intermittent feeding produced no significant effects among 6-month-old animals, whether restricted since weaning or for two weeks prior to sacrifice. Many biochemical parameters that decrease with aging in rats fed ad libitum are prevented by dietary restriction. Our results demonstrate that a reproducible biochemical process that increases with aging is also prevented with dietary restriction. The age-related, liver beta-receptor increase may be a potentially reliable marker for studying biochemical perturbations that modify life span

  17. Preliminary study on association of beta2-adrenergic receptor polymorphism with hypertension in hypertensive subjects attending Balok Health Centre, Kuantan.

    Science.gov (United States)

    Atia, A E; Norsidah, K; Nor Zamzila, A; Rafidah Hanim, M; Samsul, D; Aznan, M A M; Rashidah, A R; Norlelawati, A T

    2012-02-01

    Polymorphisms within the beta2-adrenergic receptor (ADRB2) gene have been repeatedly linked to hypertension. Among the ADRB2 polymorphisms detected, Arg16Gly and Gln27Glu codons are considered the two most important variations. The amino acid substitution at these codons may lead to abnormal regulation of ADRB2 activity. The aim of the present study was to assess the association between ADRB2 polymorphisms and hypertension. This case-control study consisted of 100 unrelated subjects (50 hypertensive and 50 matched normal controls). Arg16Gly and the Gln27Glu polymorphisms were analyzed by polymerase chain reaction-restriction fragment length polymorphism assay. There were no significant evidence of association in allelic and genotypes distribution of Arg16Gly and Glu27Gln with blood pressure and hypertension. These findings suggest that the variation within codon 16 and 27 of ADRB2 gene were unlikely to confer genetic susceptibility for hypertension in our population samples. PMID:22582545

  18. Alternative-splicing in the exon-10 region of GABA(A receptor beta(2 subunit gene: relationships between novel isoforms and psychotic disorders.

    Directory of Open Access Journals (Sweden)

    Cunyou Zhao

    Full Text Available BACKGROUND: Non-coding single nucleotide polymorphisms (SNPs in GABRB2, the gene for beta(2-subunit of gamma-aminobutyric acid type A (GABA(A receptor, have been associated with schizophrenia (SCZ and quantitatively correlated to mRNA expression and alternative splicing. METHODS AND FINDINGS: Expression of the Exon 10 region of GABRB2 from minigene constructs revealed this region to be an "alternative splicing hotspot" that readily gave rise to differently spliced isoforms depending on intron sequences. This led to a search in human brain cDNA libraries, and the discovery of two novel isoforms, beta(2S1 and beta(2S2, bearing variations in the neighborhood of Exon-10. Quantitative real-time PCR analysis of postmortem brain samples showed increased beta(2S1 expression and decreased beta(2S2 expression in both SCZ and bipolar disorder (BPD compared to controls. Disease-control differences were significantly correlated with SNP rs187269 in BPD males for both beta(2S1 and beta(2S2 expressions, and significantly correlated with SNPs rs2546620 and rs187269 in SCZ males for beta(2S2 expression. Moreover, site-directed mutagenesis indicated that Thr(365, a potential phosphorylation site in Exon-10, played a key role in determining the time profile of the ATP-dependent electrophysiological current run-down. CONCLUSION: This study therefore provided experimental evidence for the importance of non-coding sequences in the Exon-10 region in GABRB2 with respect to beta(2-subunit splicing diversity and the etiologies of SCZ and BPD.

  19. Nanoscale organization of {beta}{sub 2}-adrenergic receptor-Venus fusion protein domains on the surface of mammalian cells

    Energy Technology Data Exchange (ETDEWEB)

    Vobornik, Dusan; Rouleau, Yanouchka; Haley, Jennifer [Steacie Institute for Molecular Sciences, National Research Council Canada, Ottawa, ON, Canada K1A 0R6 (Canada); Bani-Yaghoub, Mahmud [Institute for Biological Sciences, National Research Council Canada, Ottawa, ON, Canada K1A 0R6 (Canada); Taylor, Rod [Steacie Institute for Molecular Sciences, National Research Council Canada, Ottawa, ON, Canada K1A 0R6 (Canada); Johnston, Linda J., E-mail: Linda.Johnston@nrc-cnrc.gc.ca [Steacie Institute for Molecular Sciences, National Research Council Canada, Ottawa, ON, Canada K1A 0R6 (Canada); Pezacki, John Paul, E-mail: John.Pezacki@nrc-cnrc.gc.ca [Steacie Institute for Molecular Sciences, National Research Council Canada, Ottawa, ON, Canada K1A 0R6 (Canada)

    2009-04-24

    Adrenergic receptors are a key component of nanoscale multiprotein complexes that are responsible for controlling the beat rate in a mammalian heart. We demonstrate the ability of near-field scanning optical microscopy (NSOM) to visualize {beta}{sub 2}-adrenergic receptors ({beta}{sub 2}AR) fused to the GFP analogue Venus at the nanoscale on HEK293 cells. The expression of the {beta}{sub 2}AR-Venus fusion protein was tightly controlled using a tetracycline-induced promoter. Both the size and density of the observed nanoscale domains are dependent on the level of induction and thus the level of protein expression. At concentrations between 100 and 700 ng/ml of inducer doxycycline, the size of domains containing the {beta}{sub 2}AR-Venus fusion protein appears to remain roughly constant, but the number of domains per cell increase. At 700 ng/ml doxycycline the functional receptors are organized into domains with an average diameter of 150 nm with a density similar to that observed for the native protein on primary murine cells. By contrast, larger micron-sized domains of {beta}{sub 2}AR are observed in the membrane of the HEK293 cells that stably overexpress {beta}{sub 2}AR-GFP and {beta}{sub 2}AR-eYFP. We conclude that precise chemical control of gene expression is highly advantageous for the use {beta}{sub 2}AR-Venus fusion proteins as models for {beta}{sub 2}AR function. These observations are critical for designing future cell models and assays based on {beta}{sub 2}AR, since the receptor biology is consistent with a relatively low density of nanoscale receptor domains.

  20. Signaling through urokinase and urokinase receptor in lung cancer cells requires interactions with beta1 integrins.

    Science.gov (United States)

    Tang, Chi-Hui; Hill, Marla L; Brumwell, Alexis N; Chapman, Harold A; Wei, Ying

    2008-11-15

    The urokinase receptor (uPAR) is upregulated upon tumor cell invasion and correlates with poor lung cancer survival. Although a cis-interaction with integrins has been ascribed to uPAR, whether this interaction alone is critical to urokinase (uPA)- and uPAR-dependent signaling and tumor promotion is unclear. Here we report the functional consequences of point mutations of uPAR (H249A-D262A) that eliminate beta1 integrin interactions but maintain uPA binding, vitronectin attachment and association with alphaV integrins, caveolin and epidermal growth factor receptor. Disruption of uPAR interactions with beta1 integrins recapitulated previously reported findings with beta1-integrin-derived peptides that attenuated matrix-dependent ERK activation, MMP expression and in vitro migration by human lung adenocarcinoma cell lines. The uPAR mutant cells acquired enhanced capacity to adhere to vitronectin via uPAR-alphaVbeta5-integrin, rather than through the uPAR-alpha3beta1-integrin complex and they were unable to initiate uPA signaling to activate ERK, Akt or Stat1. In an orthotopic lung cancer model, uPAR mutant cells exhibited reduced tumor size compared with cells expressing wild-type uPAR. Taken together, the results indicate that uPAR-beta1-integrin interactions are essential to signals induced by integrin matrix ligands or uPA that support lung cancer cell invasion in vitro and progression in vivo. PMID:18940913

  1. Signal processing in the TGF-beta superfamily ligand-receptor network.

    Directory of Open Access Journals (Sweden)

    Jose M G Vilar

    2006-01-01

    Full Text Available The TGF-beta pathway plays a central role in tissue homeostasis and morphogenesis. It transduces a variety of extracellular signals into intracellular transcriptional responses that control a plethora of cellular processes, including cell growth, apoptosis, and differentiation. We use computational modeling to show that coupling of signaling with receptor trafficking results in a highly versatile signal-processing unit, able to sense by itself absolute levels of ligand, temporal changes in ligand concentration, and ratios of multiple ligands. This coupling controls whether the response of the receptor module is transient or permanent and whether or not different signaling channels behave independently of each other. Our computational approach unifies seemingly disparate experimental observations and suggests specific changes in receptor trafficking patterns that can lead to phenotypes that favor tumor progression.

  2. TGF-{beta} receptors, in a Smad-independent manner, are required for terminal skeletal muscle differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Droguett, Rebeca; Cabello-Verrugio, Claudio; Santander, Cristian [Centro de Regulacion Celular y Patologia, Centro de Regeneracion y Envejecimiento (CARE), Departamento de Biologia Celular y Molecular, MIFAB, Pontificia Universidad Catolica de Chile, Santiago (Chile); Brandan, Enrique, E-mail: ebrandan@bio.puc.cl [Centro de Regulacion Celular y Patologia, Centro de Regeneracion y Envejecimiento (CARE), Departamento de Biologia Celular y Molecular, MIFAB, Pontificia Universidad Catolica de Chile, Santiago (Chile)

    2010-09-10

    Skeletal muscle differentiation is strongly inhibited by transforming growth factor type {beta} (TGF-{beta}), although muscle formation as well as regeneration normally occurs in an environment rich in this growth factor. In this study, we evaluated the role of intracellular regulatory Smads proteins as well as TGF-{beta}-receptors (TGF-{beta}-Rs) during skeletal muscle differentiation. We found a decrease of TGF-{beta} signaling during differentiation. This phenomenon is explained by a decline in the levels of the regulatory proteins Smad-2, -3, and -4, a decrease in the phosphorylation of Smad-2 and lost of nuclear translocation of Smad-3 and -4 in response to TGF-{beta}. No change in the levels and inhibitory function of Smad-7 was observed. In contrast, we found that TGF-{beta}-R type I (TGF-{beta}-RI) and type II (TGF-{beta}-RII) increased on the cell surface during skeletal muscle differentiation. To analyze the direct role of the serine/threonine kinase activities of TGF-{beta}-Rs, we used the specific inhibitor SB 431542 and the dominant-negative form of TGF-{beta}-RII lacking the cytoplasmic domain. The TGF-{beta}-Rs were important for successful muscle formation, determined by the induction of myogenin, creatine kinase activity, and myosin. Silencing of Smad-2/3 expression by specific siRNA treatments accelerated myogenin, myosin expression, and myotube formation; although when SB 431542 was present inhibition in myosin induction and myotube formation was observed, suggesting that these last steps of skeletal muscle differentiation require active TGF-{beta}-Rs. These results suggest that both down-regulation of Smad regulatory proteins and cell signaling through the TGF-{beta} receptors independent of Smad proteins are essential for skeletal muscle differentiation.

  3. Recruitment of beta-arrestin2 to the dopamine D2 receptor: insights into anti-psychotic and anti-parkinsonian drug receptor signaling

    DEFF Research Database (Denmark)

    Klewe, Ib V; Nielsen, Søren M; Tarpø, Louise;

    2008-01-01

    of a Bioluminescence Resonance Energy Transfer (BRET) assay for measuring dopamine induced recruitment of human beta-arrestin2 to the human dopamine D2 receptor. Dopamine, as well as the dopamine receptor agonists pramipexole and quinpirole, acted as full agonists in the assay as reflected by their ability to elicit...

  4. Estrogen and the selective estrogen receptor modulator (SERM) protection against cell death in estrogen receptor alpha and beta expressing U2OS cells

    OpenAIRE

    Kallio, Anu; Guo, Tao; Lamminen, Elisa; Seppänen, Jani; Kangas, Lauri; Väänänen, H Kalervo; Härkönen, Pirkko

    2008-01-01

    Estrogen and the selective estrogen receptor modulator (SERM) protection against cell death in estrogen receptor alpha and beta expressing U2OS cells SWEDEN (Kallio, Anu) SWEDEN Received: 2007-12-01 Revised: 2008-03-12 Accepted: 2008-03-12

  5. Nuclear hormone receptor NHR-49 controls fat consumption and fatty acid composition in C. elegans.

    Directory of Open Access Journals (Sweden)

    Marc R Van Gilst

    2005-02-01

    Full Text Available Mammalian nuclear hormone receptors (NHRs, such as liver X receptor, farnesoid X receptor, and peroxisome proliferator-activated receptors (PPARs, precisely control energy metabolism. Consequently, these receptors are important targets for the treatment of metabolic diseases, including diabetes and obesity. A thorough understanding of NHR fat regulatory networks has been limited, however, by a lack of genetically tractable experimental systems. Here we show that deletion of the Caenorhabditis elegans NHR gene nhr-49 yielded worms with elevated fat content and shortened life span. Employing a quantitative RT-PCR screen, we found that nhr-49 influenced the expression of 13 genes involved in energy metabolism. Indeed, nhr-49 served as a key regulator of fat usage, modulating pathways that control the consumption of fat and maintain a normal balance of fatty acid saturation. We found that the two phenotypes of the nhr-49 knockout were linked to distinct pathways and were separable: The high-fat phenotype was due to reduced expression of enzymes in fatty acid beta-oxidation, and the shortened adult life span resulted from impaired expression of a stearoyl-CoA desaturase. Despite its sequence relationship with the mammalian hepatocyte nuclear factor 4 receptor, the biological activities of nhr-49 were most similar to those of the mammalian PPARs, implying an evolutionarily conserved role for NHRs in modulating fat consumption and composition. Our findings in C. elegans provide novel insights into how NHR regulatory networks are coordinated to govern fat metabolism.

  6. Role of beta-arrestin 2 downstream of dopamine receptors in the basal ganglia

    Directory of Open Access Journals (Sweden)

    Thomas eDel'Guidice

    2011-09-01

    Full Text Available Multifunctional scaffolding protein beta-arrestins (βArr and the G protein receptor kinases (GRK are involved in the desensitization of several G protein coupled-receptors (GPCR. However, arrestins can also contribute to GPCR signaling independently from G proteins. In this review, we focus on the role of βArr in the regulation of dopamine receptor functions in the striatum. First, we present in vivo evidence supporting a role for these proteins in the regulation of dopamine receptor desensitization. Second, we provide an overview of the roles of βArr-2 in the regulation of ERK/MAPkinases and Akt/GSK3 signaling pathways downstream of the D1 and D2 dopamine receptors. Thereafter, we examine the possible involvement of βArr-mediated signaling in the action of dopaminergic drugs used for the treatment of mental disorders. Finally, we focus on different potential cellular proteins regulated by βArr-mediated signaling which could contribute to the regulation of behavioral responses to dopamine. Overall, the identification of a cell signaling function for βArr downstream of dopamine receptors underscores the intricate complexity of the intertwined mechanisms regulating and mediating cell signaling in the basal ganglia. Understanding these mechanisms may lead to a better comprehension of the several roles played by these structures in the regulation of mood and to the development of new psychoactive drugs having better therapeutic efficacy.

  7. Alpha-amino acid behaves differently from beta- or gamma-amino acids as treated by trimetaphosphate.

    Science.gov (United States)

    Gao, X; Liu, Y; Xu, P X; Cai, Y M; Zhao, Y F

    2008-01-01

    The condensation reactions of sodium trimetaphosphate with single amino acids, namely glycine, L-alanine, beta-alanine and gamma-aminobutyric acid or pairs of these amino acids were reinvestigated by electrospray ion-trap mass spectrometry and high performance liquid chromatography. It was found when mixtures were treated by sodium trimetaphosphate only in the presence of alpha-amino acid dipeptides were formed. Without addition of alpha-amino acids, the beta-amino acid or gamma-aminobutyric acid could not form peptide either by themselves or with their mixtures under the same conditions. From the data it is concluded that phosphate might select alpha-amino acids to produce the peptides being important precursors for the origin of life. PMID:17973074

  8. Overexpression of estrogen receptor beta alleviates the toxic effects of beta-amyloid protein on PC12 cells via non-hormonal ligands

    Institute of Scientific and Technical Information of China (English)

    Hui Wang; Lihui Si; Xiaoxi Li; Weiguo Deng; Haimiao Yang; Yuyan Yang; Yan Fu

    2012-01-01

    After binding to the estrogen receptor, estrogen can alleviate the toxic effects of beta-amyloid protein, and thereby exert a therapeutic effect on Alzheimer's disease patients. Estrogen can increase the incidence of breast carcinoma and endometrial cancer in post-menopausal women, so it is not suitable for clinical treatment of Alzheimer's disease. There is recent evidence that the estrogen receptor can exert its neuroprotective effects without estrogen dependence. Real-time quantitative PCR and flow cytometry results showed that, compared with non-transfected PC12 cells, adenovirus-mediated estrogen receptor β gene-transfected PC12 cells exhibited lower expression of tumor necrosis factor α and interleukin 1β under stimulation with beta-amyloid protein and stronger protection from apoptosis. The Akt-specific inhibitor Abi-2 decreased the anti-inflammatory and anti-apoptotic effects of estrogen receptor β gene-transfection. These findings suggest that overexpression of estrogen receptor β can alleviate the toxic effect of beta-amyloid protein on PC12 cells, without estrogen dependence. The Akt pathway is one of the potential means for the anti-inflammatory and anti-apoptotic effects of the estrogen receptor.

  9. Regulation of dioxin receptor function by different beta-carboline alkaloids

    Energy Technology Data Exchange (ETDEWEB)

    Haarmann-Stemmann, Thomas; Goetz, Christine; Krug, Nathalie; Bothe, Hanno; Abel, Josef [Heinrich-Heine-Universitaet Duesseldorf gGmbH, Institut fuer Umweltmedizinische Forschung (IUF), Duesseldorf (Germany); Sendker, Jandirk; Proksch, Peter [Heinrich-Heine-Universitaet, Institut fuer Pharmazeutische Biologie und Biotechnologie, Duesseldorf (Germany); Fritsche, Ellen [Heinrich-Heine-Universitaet Duesseldorf gGmbH, Institut fuer Umweltmedizinische Forschung (IUF), Duesseldorf (Germany); University Hospital, RWTH Aachen, Department of Dermatology, Aachen (Germany)

    2010-08-15

    The dioxin receptor, also known as arylhydrocarbon receptor (AhR), is a ligand-activated transcription factor that mediates the toxicity of dioxins and related environmental contaminants. In addition, there is a growing list of natural compounds, mainly plant polyphenols that can modulate AhR function and downstream signaling with quite unknown consequences for cellular function. We investigate the potential of four different {beta}-carboline alkaloids to stimulate AhR signaling in human hepatoma cells and keratinocytes. Three test substances, namely rutaecarpine, annomontine and xestomanzamine A, increase AhR-driven reporter gene activity as well as expression of two AhR target genes in a dose-dependent and time-dependent manner. Additionally, the three test alkaloids stimulate cytochrome P450 (CYP) 1 enzyme activity without showing any antagonistic effects regarding benzo(a)pyrene-stimulated CYP1 activation. The AhR-activating property of the {beta}-carbolines is completely abrogated in AhR-deficient cells providing evidence that rutaecarpine, annomontine and xestomanzamine A are natural stimulators of the human AhR. The toxicological relevance of beta-carboline-mediated AhR activation is discussed. (orig.)

  10. Identification of alpha beta and gamma delta T cell receptor-positive cells

    DEFF Research Database (Denmark)

    Geisler, C; Larsen, J K; Plesner, T

    1988-01-01

    distribution and function of these different T cells. In immunofluorescence studies gamma delta TCR+ cells have been identified as CD3+WT-31- or CD3+CD4-CD8- cells. However, this may not be the optimal procedure because gamma delta TCR+ cells are weakly WT-31+, and some are CD8+. The aim of this study......Two lineages of T lymphocytes bearing the CD3 antigen can be defined on the basis of the nature of the heterodimeric receptor chain (alpha beta or gamma delta T cell receptor (TCR) expressed. Precise identification of alpha beta and gamma delta TCR+ cells is essential when studying the tissue...... was to evaluate a panel of monoclonal antibodies (MoAb) directed against different chains of the TCR-T3 complex for a more precise identification of alpha beta+ and gamma delta TCR+ cells in flow cytometric studies. We found that the MoAb anti-Ti-gamma A and delta-TCS-1, recognizing the TCR-gamma and the TCR...

  11. Hypoxia and glucose independently regulate the beta-adrenergic receptor-adenylate cyclase system in cardiac myocytes.

    OpenAIRE

    Rocha-Singh, K J; Honbo, N Y; Karliner, J S

    1991-01-01

    We explored the effects of two components of ischemia, hypoxia and glucose deprivation, on the beta-adrenergic receptor (beta AR)-adenylate cyclase system in a model of hypoxic injury in cultured neonatal rat ventricular myocytes. After 2 h of hypoxia in the presence of 5 mM glucose, cell surface beta AR density (3H-CGP-12177) decreased from 54.8 +/- 8.4 to 39 +/- 6.3 (SE) fmol/mg protein (n = 10, P less than 0.025), while cytosolic beta AR density (125I-iodocyanopindolol [ICYP]) increased by...

  12. New insights in dihydropyrimidine dehydrogenase deficiency: a pivotal role for beta-aminoisobutyric acid?

    Science.gov (United States)

    Van Kuilenburg, André B P; Stroomer, Alida E M; Van Lenthe, Henk; Abeling, Nico G G M; Van Gennip, Albert H

    2004-04-01

    DPD (dihydropyrimidine dehydrogenase) constitutes the first step of the pyrimidine degradation pathway, in which the pyrimidine bases uracil and thymine are catabolized to beta-alanine and the R-enantiomer of beta-AIB (beta-aminoisobutyric acid) respectively. The S-enantiomer of beta-AIB is predominantly derived from the catabolism of valine. It has been suggested that an altered homoeostasis of beta-alanine underlies some of the clinical abnormalities encountered in patients with a DPD deficiency. In the present study, we demonstrated that only a slightly decreased concentration of beta-alanine was present in the urine and plasma, whereas normal levels of beta-alanine were present in the cerebrospinal fluid of patients with a DPD deficiency. Therefore the metabolism of beta-alanine-containing peptides, such as carnosine, may be an important factor involved in the homoeostasis of beta-alanine in patients with DPD deficiency. The mean concentration of beta-AIB was approx. 2-3-fold lower in cerebrospinal fluid and urine of patients with a DPD deficiency, when compared with controls. In contrast, strongly decreased levels (10-fold) of beta-AIB were present in the plasma of DPD patients. Our results demonstrate that, under pathological conditions, the catabolism of valine can result in the production of significant amounts of beta-AIB. Furthermore, the observation that the R-enantiomer of beta-AIB is abundantly present in the urine of DPD patients suggests that significant cross-over exists between the thymine and valine catabolic pathways. PMID:14705962

  13. Stereoselective and nonstereoselective effects of ibuprofen enantiomers on mitochondrial beta-oxidation of fatty acids

    Energy Technology Data Exchange (ETDEWEB)

    Freneaux, E.; Fromenty, B.; Berson, A.; Labbe, G.; Degott, C.; Letteron, P.; Larrey, D.; Pessayre, D. (Unite de Recherches de Physiolopathologie Hepatique (INSERM U-24), Hopital Beaujon, Clichy (France))

    1990-11-01

    The effects of the R-(-) and S-(+)ibuprofen enantiomers were first studied in vitro with mouse liver mitochondria incubated in the presence of various concentrations of exogenous coenzyme A. In the presence of a low concentration of coenzyme A (2.5 microM), the R-(-)enantiomer (which forms an acylcoenzyme A) inhibited stereoselectively the beta oxidation of (1-{sup 14}C)palmitic acid but not that of (1-{sup 14}C)palmitoyl-L-carnitine (which can directly enter the mitochondria). In the presence, however, of a concentration of coenzyme A (50 microM) reproducing that present in liver cell cytosol, both enantiomers (2 mM) slightly inhibited the beta oxidation of (1-{sup 14}C)palmitic acid and markedly inhibited the beta oxidation of (1-{sup 14}C)octanoic acid and (1-{sup 14}C)butyric acid. In vivo, both enantiomers (1 mmol.kg-1) similarly inhibited the formation of ({sup 14}C)CO{sub 2} from (1-{sup 14}C)fatty acids. Both enantiomers similarly decreased plasma ketone bodies. Both similarly increased hepatic triglycerides, and both produced mild microvesicular steatosis of the liver. We conclude that both ibuprofen enantiomers inhibit beta oxidation of fatty acids in vitro and in vivo. In addition, the R-(-)enantiomer may stereoselectively sequester coenzyme A; at low concentrations of coenzyme A in vitro, this may stereoselectively inhibit the mitochondrial uptake and beta oxidation of long chain fatty acids.

  14. Indices of brain beta-adrenergic receptor signal transduction in the learned helplessness animal model of depression.

    Science.gov (United States)

    Gurguis, G N; Kramer, G; Petty, F

    1996-01-01

    Both stress response and antidepressant drug action may be mediated by beta-adrenergic receptors (beta AR). Since learned helplessness is a stress-induced animal model of depression, beta AR are relevant to investigate in this model. To date, studies have measured changes in total receptor density (RT), but have not examined more detailed aspects of signal transduction mechanisms such as coupling of the receptor to GS protein. We have investigated brain beta AR coupling in the frontal cortex, hippocampus and hypothalamus of rats exposed to inescapable shock and then tested for learned helplessness, and in both tested and naive controls using [125I]-iodocyanopindolol (ICYP) as the ligand. Both antagonist-saturation and agonist-displacement experiments were conducted, and the specificity for the beta AR was optimized by excluding ICYP binding to 5HT1B receptors. The percentage receptor density in the high-conformational state (%RH) and the ratio of agonist (isoproterenol) dissociation constant from the receptor in the low-/high-conformational states (KL/KH) were used as indices of coupling to GS protein. No significant differences were found between rats developing learned helplessness and non-helpless rats after inescapable stress in any parameter measured in any brain region. In the frontal cortex, exposure to inescapable shock induced beta AR uncoupling from GS protein as suggested by a low KL/KH ratio both in helpless and non-helpless rats but not in either control group. In the hypothalamus, there were trends for higher RL, RT and KL/KH ratio in helpless rats and stressed controls compared to naive controls. These findings suggest that beta AR binding parameters in frontal cortex, hippocampus or hypothalamus did not differentiate between helpless and non-helpless rats. Changes in beta AR coupling observed in these brain regions may reflect effects of stress, which appeared to be region-specific, rather than stress-induced behavioral depression.

  15. 164Ile allele in the beta2-Adrenergic receptor gene is associated with risk of elevated blood pressure in women. The Copenhagen City Heart Study

    DEFF Research Database (Denmark)

    Sethi, Amar A; Tybjaerg-Hansen, Anne; Jensen, Gorm B;

    2005-01-01

    Since beta2-adrenergic receptors are important regulators of blood pressure, genetic variation in this receptor could explain risk of elevated blood pressure in selected individuals. We tested the hypothesis that Gly16Arg, Gln27Glu, and Thr164Ile in the beta2-adrenergic receptor gene associated w...

  16. Extracellular ATP stimulates exocytosis via localized Ca(2+) release from acidic stores in rat pancreatic beta cells.

    Science.gov (United States)

    Xie, Li; Zhang, Ming; Zhou, Wei; Wu, Zhengxing; Ding, Jiuping; Chen, Liangyi; Xu, Tao

    2006-04-01

    Three different methods, membrane capacitance (C(m)) measurement, amperometry and FM dye labeling were used to investigate the role of extracellular ATP in insulin secretion from rat pancreatic beta cells. We found that extracellular application of ATP mobilized intracellular Ca(2+) stores and synchronously triggered vigorous exocytosis. No influence of ATP on the readily releasable pool of vesicles was observed, which argues against a direct modulation of the secretory machinery at a level downstream of Ca(2+) elevation. The stimulatory effects of ATP were greatly reduced by intracellular perfusion of BAPTA but not EGTA, suggesting a close spatial association of fusion sites with intracellular Ca(2+) releasing sites. ATP-induced Ca(2+) transients and exocytosis were not blocked by thapsigargin (TG), by a ryanodine receptor antagonist or by dissipation of pH in acidic stores by monensin alone, but they were greatly attenuated by IP(3) receptor inhibition as well as ionomycin plus monensin, suggesting involvement of IP(3)-sensitive acidic Ca(2+) stores. Taken together, our data suggest that extracellular ATP triggers exocytosis by mobilizing spatially limited acidic Ca(2+) stores through IP(3) receptors. This mechanism may explain how insulin secretion from the pancreas is coordinated through diffusible ATP that is co-released with insulin. PMID:16536741

  17. Novel retinoic acid receptor ligands in Xenopus embryos.

    OpenAIRE

    Blumberg, B; Bolado, J; Derguini, F; Craig, A G; Moreno, T A; Chakravarti, D; Heyman, R A; Buck, J.; Evans, R M

    1996-01-01

    Retinoids are a large family of natural and synthetic compounds related to vitamin A that have pleiotropic effects on body physiology, reproduction, immunity, and embryonic development. The diverse activities of retinoids are primarily mediated by two families of nuclear retinoic acid receptors, the RARs and RXRs. Retinoic acids are thought to be the only natural ligands for these receptors and are widely assumed to be the active principle of vitamin A. However, during an unbiased, bioactivit...

  18. Beta-arrestin-mediated activation of MAPK by inverse agonists reveals distinct active conformations for G protein-coupled receptors.

    OpenAIRE

    Azzi, Mounia; Pascale G. Charest; Angers, Stéphane; Rousseau, Guy; Kohout, Trudy; Bouvier, Michel; Piñeyro, Graciela

    2003-01-01

    It is becoming increasingly clear that signaling via G protein-coupled receptors is a diverse phenomenon involving receptor interaction with a variety of signaling partners. Despite this diversity, receptor ligands are commonly classified only according to their ability to modify G protein-dependent signaling. Here we show that beta2AR ligands like ICI118551 and propranolol, which are inverse agonists for Gs-stimulated adenylyl cyclase, induce partial agonist responses for the mitogen-activat...

  19. Molecular determinants of desensitization and assembly of the chimeric GABA(A) receptor subunits (alpha1/gamma2) and (gamma2/alpha1) in combinations with beta2 and gamma2

    DEFF Research Database (Denmark)

    Elster, L; Kristiansen, U; Pickering, D S;

    2001-01-01

    )beta2gamma2 subunit combinations formed functional receptor complexes as shown by whole-cell patch-clamp recordings and [3H]muscimol and [3H]flunitrazepam binding. Moreover, the surface immunofluorescence staining of Sf-9 cells expressing the (alpha1/gamma2)-containing receptors was pronounced......Two gamma-aminobutyric acid(A) (GABA(A)) receptor chimeras were designed in order to elucidate the structural requirements for GABA(A) receptor desensitization and assembly. The (alpha1/gamma2) and (gamma2/alpha1) chimeric subunits representing the extracellular N-terminal domain of alpha1 or gamma......2 and the remainder of the gamma2 or alpha1 subunits, respectively, were expressed with beta2 and beta2gamma2 in Spodoptera frugiperda (Sf-9) cells using the baculovirus expression system. The (alpha1/gamma2)beta2 and (alpha1/gamma2)beta2gamma2 but not the (gamma2/alpha1)beta2 and (gamma2/alpha1...

  20. Structure of the T cell receptor in a Ti alpha V beta 2, alpha V beta 8-positive T cell line

    DEFF Research Database (Denmark)

    Hou, X; Dietrich, J; Kuhlmann, J;

    1994-01-01

    not known; however, it has been suggested that each TcR contains two Ti dimers. To gain insight into the structure of the TcR we constructed a Ti alpha V beta 2, alpha V beta 8-positive T cell line which expressed the endogenous human TiV beta 8 and the transfected mouse TiV beta 2 both in association......The T cell receptor (TcR) is composed of at least six different polypeptide chains consisting of the clonotypic Ti heterodimer (Ti alpha beta or Ti gamma delta) and the noncovalently associated CD3 chains (CD3 gamma delta epsilon zeta). The exact number of subunits constituting the TcR is still...... with the endogenous Ti alpha and CD3 chains at the cell surface. Preclearing experiments with radioiodinated cell lysate prepared with digitonin lysis buffer demonstrated that depleting the lysate of Ti alpha V beta 8 by immunoprecipitation with anti V beta 8 monoclonal antibody (mAb) did not reduce the amount of Ti...

  1. Roles of oestrogen receptors alpha and beta in behavioural neuroendocrinology: beyond Yin/Yang.

    Science.gov (United States)

    Rissman, E F

    2008-06-01

    Oestrogen receptor beta (ERbeta) was discovered more than 10 years ago. It is widely distributed in the brain. In some areas, such as the entorhinal cortex, it is present as the only ER, whereas in other regions, such as the bed nucleus of the stria terminalis and preoptic area, it can be found co-expressed with ERalpha, often within the same neurones. These ERs share ligands, and there are several complex relationships between the two receptors. Initially, the relationship between them was labelled as 'yin/yang', meaning that the actions of each complemented those of the other, but now, years later, other relationships have been described. Based on evidence from neuroendocrine and behavioural studies, three types of interactions between the two oestrogen receptors are described in this review. The first relationship is antagonistic; this is evident from studies on the role of oestrogen in spatial learning. When oestradiol is given in a high, chronic dose, spatial learning is impaired. This action of oestradiol requires ERalpha, and when ERbeta is not functional, lower doses of oestradiol have this negative effect on behaviour. The second relationship between the two receptors is one that is synergistic, and this is illustrated in the combined effects of the two receptors on the production of the neuropeptide oxytocin and its receptor. The third relationship is sequential; separate actions of the two receptors are postulated in activation and organisation of sexually dimorphic reproductive behaviours. Future studies on all of these topics will inform us about how ER selective ligands might affect oestrogen functions at the organismal level.

  2. Ionotropic excitatory amino acid receptor ligands. Synthesis and pharmacology of a new amino acid AMPA antagonist

    DEFF Research Database (Denmark)

    Madsen, U; Sløk, F A; Stensbøl, T B;

    2000-01-01

    We have previously described the potent and selective (RS)-2-amino-3-(3-hydroxy-5-methyl-4-isoxazolyl)propionic acid (AMPA) receptor agonist, (RS)-2-amino-3-(3-carboxy-5-methyl-4-isoxazolyl)propionic acid (ACPA), and the AMPA receptor antagonist (RS)-2-amino-3-[3-(carboxymethoxy)-5-methyl-4-isoxa...

  3. Enhanced negative chronotropy by inhibitory receptors in transgenic heart overexpressing beta(2)-adrenoceptors.

    Science.gov (United States)

    Du, X J; Vincan, E; Percy, E; Woodcock, E A

    2000-03-15

    Transgenic (TG) mice overexpressing beta(2)-adrenoceptors (AR) in the heart have enhanced beta-adrenergic activity. Since the degree of beta-adrenergic activation influences the negative chronotropic control of heart rate (HR), we studied the inhibitory effect of cholinergic and purinergic stimulation on HR in TG and wild-type (WT) control mice. Bradycardia in response to vagal nerve stimulation and administration of acetylcholine or adenosine was studied in anesthetised animals and perfused hearts. Basal HR was significantly higher in TG than WT mice (P<0.01). Electrical stimulation of vagal nerves (1-32 Hz) induced a Hz-dependent reduction in HR and the response was more pronounced in TG than WT groups (P<0.01). In perfused hearts, HR reduction by acetylcholine (ACh) was more pronounced with EC(50) 110-fold lower in TG than WT hearts. Adenosine-induced bradycardia, which was abolished by a P(1) antagonist, was more pronounced in TG hearts. After pre-treatment with pertussis toxin (PT, 100 microg/kg), bradycardia by vagal nerve stimulation or ACh remained unchanged in WT, but markedly inhibited in TG hearts (both P<0.01). Conversely, inhibiting guanylyl cyclase with LY83583 (30 microM) or nitric oxide synthase with L-NMMA (100 microM) attenuated HR reduction by vagal nerve stimulation in WT but not in TG hearts. Immunobloting assay showed similar G(ialpha2) abundance in TG and WT hearts. Thus, cardiac overexpression of beta(2)AR with high beta-adrenergic activity leads to hypersensitivity of inhibitory receptors controlling HR due to increase in activity of PT-sensitive G-proteins.

  4. Beta-alanine/alpha-ketoglutarate aminotransferase for 3-hydroxypropionic acid production

    Energy Technology Data Exchange (ETDEWEB)

    Jessen, Holly Jean; Liao, Hans H; Gort, Steven John; Selifonova, Olga V

    2014-11-18

    The present disclosure provides novel beta-alanine/alpha ketoglutarate aminotransferase nucleic acid and protein sequences having increased biological activity. Also provided are cells containing such enzymes, as well as methods of their use, for example to produce malonyl semialdehyde and downstream products thereof, such as 3-hydroxypropionic acid and derivatives thereof.

  5. Beta-alanine/alpha-ketoglutarate aminotransferase for 3-hydroxypropionic acid production

    Energy Technology Data Exchange (ETDEWEB)

    Jessen, Holly Jean (Chanhassen, MN); Liao, Hans H. (Eden Prairie, MN); Gort, Steven John (Apple Valley, MN); Selifonova, Olga V. (Plymouth, MN)

    2011-10-04

    The present disclosure provides novel beta-alanine/alpha ketoglutarate aminotransferase nucleic acid and protein sequences having increased biological activity. Also provided are cells containing such enzymes, as well as methods of their use, for example to produce malonyl semialdehyde and downstream products thereof, such as 3-hydroxypropionic acid and derivatives thereof.

  6. Troglitazone stimulates {beta}-arrestin-dependent cardiomyocyte contractility via the angiotensin II type 1{sub A} receptor

    Energy Technology Data Exchange (ETDEWEB)

    Tilley, Douglas G., E-mail: douglas.tilley@jefferson.edu [Department of Pharmaceutical Sciences, Jefferson School of Pharmacy, Thomas Jefferson University (United States); Center for Translational Medicine, Thomas Jefferson University (United States); Nguyen, Anny D. [Department of Pharmaceutical Sciences, Jefferson School of Pharmacy, Thomas Jefferson University (United States); Rockman, Howard A. [Department of Medicine, Duke University Medical Center (United States); Department of Cell Biology, Duke University Medical Center (United States); Department of Molecular Genetics and Microbiology, Duke University Medical Center (United States)

    2010-06-11

    Peroxisome proliferator-activated receptor {gamma} (PPAR{gamma}) agonists are commonly used to treat cardiovascular diseases, and are reported to have several effects on cardiovascular function that may be due to PPAR{gamma}-independent signaling events. Select angiotensin receptor blockers (ARBs) interact with and modulate PPAR{gamma} activity, thus we hypothesized that a PPAR{gamma} agonist may exert physiologic effects via the angiotensin II type 1{sub A} receptor (AT1{sub A}R). In AT1{sub A}R-overexpressing HEK 293 cells, both angiotensin II (Ang II) and the PPAR{gamma} agonist troglitazone (Trog) enhanced AT1{sub A}R internalization and recruitment of endogenous {beta}-arrestin1/2 ({beta}arr1/2) to the AT1{sub A}R. A fluorescence assay to measure diacylglycerol (DAG) accumulation showed that although Ang II induced AT1{sub A}R-G{sub q} protein-mediated DAG accumulation, Trog had no impact on DAG generation. Trog-mediated recruitment of {beta}arr1/2 was selective to AT1{sub A}R as the response was prevented by an ARB- and Trog-mediated {beta}arr1/2 recruitment to {beta}1-adrenergic receptor ({beta}1AR) was not observed. In isolated mouse cardiomyocytes, Trog increased both % and rate of cell shortening to a similar extent as Ang II, effects which were blocked with an ARB. Additionally, these effects were found to be {beta}arr2-dependent, as cardiomyocytes isolated from {beta}arr2-KO mice showed blunted contractile responses to Trog. These findings show for the first time that the PPAR{gamma} agonist Trog acts at the AT1{sub A}R to simultaneously block G{sub q} protein activation and induce the recruitment of {beta}arr1/2, which leads to an increase in cardiomyocyte contractility.

  7. Autoradiographic quantitation of. beta. -adrenergic receptors on neural cells in primary cultures. 1. Pharmacological studies of (/sup 125/I)pindolol binding of individual astroglial cells

    Energy Technology Data Exchange (ETDEWEB)

    Burgess, S.K.; McCarthy, K.D. (North Carolina Univ., Chapel Hill (USA). School of Medicine)

    1985-05-27

    The current investigation was undertaken to determine whether the binding of (/sup 125/I)pindolol (*IPIN) to immunocytochemically stained cultured cells, as measured by quantitative autoradiography, would fulfill the usual pharmacological criteria for specific ..beta..-adrenergic receptor binding. *IPIN binding experiments were carried out on individual astroglia obtained from neonatal rat cerebral cortex and grown as primary cultures on polylysine-coated glass slides. Autoradiographic silver grains on cells which stained for the intracellular astroglial marker, glial fibrillary acidic protein (GFAP), were quantified by a microcomputer-based video digitizing system. This study is a demonstration of receptor binding parameters derived from single cells in a known population, and represents a novel approach to the problem of assessing cell-type specific receptors on neural cells in mixed primary cultures.

  8. Normotensive sodium loading in conscious dogs: Regulation of renin secretion during beta receptor blockade

    DEFF Research Database (Denmark)

    Bie, Peter; Mølstrøm, Simon; Wamberg, Søren

    2009-01-01

    that in this setting, renin secretion and renin-dependent sodium excretion are controlled by via the renal nerves and therefore eliminated or reduced by blocking the action of norepinephrine on the juxtaglomerular cells with the beta1-receptor antagonist metoprolol. This was tested in conscious dogs by infusion of NaCl...... (20 micromol/kg/min for 180 min, NaLoad) during regular or low-sodium diet (0.03 mmol/kg/d, LowNa) with and without metoprolol (2 mg/kg plus 0.9 mg/kg/h). Vasopressin V2 receptors were blocked by Otsuka compound OPC31260 to facilitate clearance measurements. Body fluid volume was maintained by servo...

  9. Biology of common beta receptor-signaling cytokines: IL-3, IL-5, and GM-CSF.

    Science.gov (United States)

    Martinez-Moczygemba, Margarita; Huston, David P

    2003-10-01

    IL-3, IL-5, and GM-CSF are related hematopoietic cytoines that are important for allergic inflammation. The receptors for human IL-5, IL-3, and GM-CSF are members of the hematopoietin receptor superfamily and are comprised of a cytokine-specific alpha chain and the common beta chain that is shared among these cytokines for signaling. Each of these cytokines contributes to the differentiation and function of leukocyte subpopulations and have clinical importance in protective immunity and in the pathophysiology of a spectrum of immunologic diseases that are as diverse as allergy and asthma, pulmonary alveolar proteinosis, neurodegenerative diseases, and malignancies. Delineating the biology of these cytokines is enabling the development of new strategies for diagnosing and treating these diseases and modulating immune responses. PMID:14564341

  10. Absence of transforming growth factor-beta type II receptor is associated with poorer prognosis in HER2-negative breast tumours

    DEFF Research Database (Denmark)

    Paiva, C E; Drigo, S A; Rosa, F E;

    2010-01-01

    BACKGROUND: The clinical relevance of transforming growth factor-beta (TGF-beta)-signalling pathway in breast carcinomas (BCs) remained elusive. This study aimed to evaluate the prognostic value of TGF-beta1 and transforming growth factor-beta type II receptor (TGF-betaRII) expression levels...... in tumour cells and their association with the established biomarkers in BC. PATIENTS AND METHODS: In 324 BC from patients with long-term follow-up, the TGF-beta1 and TGF-betaRII transcript and protein expression levels were assessed. RESULTS: TGF-beta1 and TGF-betaRII down-expression was significantly...... associated with BC. Negative TGF-beta1 and TGF-betaRII protein status was associated with the development of distant metastasis (P = 0.003 and P = 0.029, respectively). In multivariate analysis, TGF-beta1-positive tumours were associated with increased disease-free survival (DFS) [hazard ratio (HR) = 0...

  11. Proinsulin C-peptide antagonizes the profibrotic effects of TGF-beta1 via up-regulation of retinoic acid and HGF-related signaling pathways.

    Science.gov (United States)

    Hills, Claire E; Willars, Gary B; Brunskill, Nigel J

    2010-04-01

    Novel signaling roles for C-peptide have recently been discovered with evidence that it can ameliorate complications of type 1 diabetes. Here we sought to identify new pathways regulated by C-peptide of relevance to the pathophysiology of diabetic nephropathy. Microarray analysis was performed to identify genes regulated by either C-peptide and/or TGF-beta1 in a human proximal tubular cell line, HK-2. Expression of retinoic acid receptor beta (RARbeta), hepatocyte growth factor (HGF), cellular retinoic acid-binding protein II (CRABPII), vimentin, E-cadherin, Snail, and beta-catenin was assessed by immunoblotting. The cellular localization of vimentin and beta-catenin was determined by immunocytochemistry. Changes in cell morphology were assessed by phase contrast microscopy. Gene expression profiling demonstrated differential expression of 953 and 1458 genes after C-peptide exposure for 18 h or 48 h, respectively. From these, members of the antifibrotic retinoic acid (RA)- and HGF-signaling pathways were selected. Immunoblotting demonstrated that C-peptide increased RARbeta, CRABPII, and HGF. We confirmed a role for RA in reversal of TGF-beta1-induced changes associated with epithelial-mesenchymal transition, including expression changes in Snail, E-cadherin, vimetin, and redistribution of beta-catenin. Importantly, these TGF-beta1-induced changes were inhibited by C-peptide. Further, effects of TGF-beta1 on Snail and E-cadherin expression were blocked by HGF, and inhibitory effects of C-peptide were removed by blockade of HGF activity. This study identifies a novel role for HGF as an effector of C-peptide, possibly via an RA-signaling pathway, highlighting C-peptide as a potential therapy for diabetic nephropathy. PMID:20197308

  12. Amino acid preference against beta sheet through allowing backbone hydration enabled by the presence of cation

    CERN Document Server

    Sharley, John N

    2016-01-01

    It is known that steric blocking by peptide sidechains of hydrogen bonding, HB, between water and peptide groups, PGs, in beta sheets accords with an amino acid intrinsic beta sheet preference. The present observations with Quantum Molecular Dynamics, QMD, simulation with quantum mechanical treatment of every water molecule solvating a beta sheet that would be transient in nature suggest that this steric blocking is not applicable in a hydrophobic region unless a cation is present, so that the amino acid beta sheet preference due to this steric blocking is only effective in the presence of a cation. We observed backbone hydration in a polyalanine and to a lesser extent polyvaline alpha helix without a cation being present, but a cation could increase the strength of these HBs. Parallel beta sheets have a greater tendency than antiparallel beta sheets of equivalent small size to retain regular structure in solvated QMD, and a 4 strand 4 inter-PG HB chain parallel beta sheet was used. Stability was reinforced b...

  13. Up and Down Expression of Androgen Receptor,Estrogen Receptor beta and Platelet Derived Growth Factor beta by Testosterone in Aortic Vascular Smooth Muscle Tissues

    Institute of Scientific and Technical Information of China (English)

    Wu Saizhu; Lv Hongsong; Zhou Kexiang; Sun Fei; Ma Rui; Zheng Hua; Wei Heming; Rong Zhiyi

    2004-01-01

    Objectives To investigate the effects of testosterone enanthate(TE) on serum lipids and lipoproteins metabolism and the expression of androgen receptor ( AR), estrogen receptor beta ( ER -β) and platelet derived growth factor beta (PDGFR-β ) in aortic vascular smooth muscle tissues(VSMTs). Methods Forty aged male rats were randomly divided into 4 groups, group A (placebo group),group B (2.5 mg/kg intramuscular injection of TE once a week ), group C (5.0 mg/kg intramuscular injection of TE once a week ), group D ( 10.0 mg,/kg intramuscular injection of TE once a week). All animals were fed freely during 16 - week treatment periods. The expression of AR , ER - βand PDGFR - β were studied by Western bolt. Results Average serum LDL - C was lower in group D than that in group A ( p < 0.01 ).Compared with the other groups, average serum TC was also lower in group D ( p < 0.05). AR expression in aortic vascular smooth muscle tissues could be regulated by TE: 99.50 ± 21.74, 125.38 ± 28.68 and 101.98 ±15.42 for TE concentrations at 2.5 mg/kg, 5.0 mg/kgand 10.0 mg/kg, respectively , the expression of ER -β could be regulated by TE: 92.34 ± 18.68, 47.72 ±18.12, 82.13 ±23.50, and the expression of PDGFR -β could be regulated as well by TE: 219.70 ± 45.59,50.16 ± 9.72, 125.36 ± 15.74 ( Data for AR , ER - βand PDGFR - β protein band intensity were expressed with x ± s, with control group taken as 100).Conclusions This study indicates that androgens have significant effects on serum lipids and lipoprotein metabolism. Testosterone enanthate at 5.0 mg/kg can stimulate the expression of AR, but inhibite the expression of PDGFR. Testosterone enanthate at the concentrations of 5.0 mg/kg and 10.0 mg/kg can inhibite the expression of ER - β.

  14. Polimorfismos del receptor adrenérgico beta-1 y sus implicaciones farmacodinámicas

    Directory of Open Access Journals (Sweden)

    Ignacio Rodríguez

    2001-04-01

    Full Text Available Los betabloqueadores son fármacos que han demostrado eficacia
    clínica al disminuir tanto la morbilidad como la mortalidad de múltiples enfermedades cardiovasculares. Como común denominador todos los bloqueadores beta adrenérgicos antagonizan los receptores β1, produciendo en el corazón
    una respuesta inotrópica y cronotrópica negativas. Hasta la fecha se han reportado siete polimorfismos en este receptor β1 (1. En uno de ellos, la sustitución en el nucleótido 1165, genera un cambio de Arginina por Glicina en la posición 389 (Arg389Gly localizado en la cola citoplasmática del receptor que es una de las regiones de interacción con la proteína G. Estudios in vitro con las
    dos variantes polimórficas Arg389Gly del receptor, han demostrado que los receptores con Arg389 tienen una mayor interacción con la proteína G y producen más AMPc luego del estímulo con agonistas β(2. En la actualidad se desconocen tanto las implicaciones farmacoterapéuticas de estos polimorfismos, como sus frecuencias alélicas en poblaciones latinoamericanas. Este estudio pretende evaluar la frecuencia de los polimorfismos en la posición 1165 en
    individuos colombianos, y determinar si tales cambios desencadenan alguna variación en la respuesta a un medicamento bloqueador de los receptores β1 adrenérgicos.

  15. [The association between beta-adrenergic receptor gene polymorphisms and personality traits].

    Science.gov (United States)

    Numajiri, Maki; Aoki, Jun; Nishizawa, Daisuke; Kasai, Shinya; Ogai, Yasukazu; Ikeda, Kazutaka; Iwahashi, Kazuhiko

    2012-08-01

    The relationship between the polymorphisms (SNPs) of the beta-adrenergic receptor (beta-AR) gene and personality assessed by TCI (Temperament and Character Inventory), was studied among 192 healthy Japanese subjects (121 male subjects and 71 female subjects). In this study, the statistical analyses were performed overall and separately for each sex. As a result, it was shown that there were significant relationships between SD (self-directedness) and 49Ser/Gly (rs1801252) in ADRB1, P (persistence) and 389Arg/Gly (rs1801253) in ADRB1, and ST (self-transcendence) and 27Gln/Glu (rs1042714) in ADRB2 overall. Among the male subjects, there were further significant relationships between ST and 49Ser/Gly in ADRB1, NS (novelty-seeking), HA (harm avoidance) and P and 389Arg/Gly in ADRB1, and P and 64Arg/Trp(rsrs4994) in ADRB3. Among the female subjects, there were also significant relationships between SD and 49Ser/Gly in ADRB1, and C (cooperativeness) and 389Arg/Gly in ADRB1. Thus it was shown that there were correlations between beta-AR gene polymorphisms and several subscales of TCI. PMID:23012891

  16. Mycophenolate mofetil modulates adhesion receptors of the beta1 integrin family on tumor cells: impact on tumor recurrence and malignancy

    International Nuclear Information System (INIS)

    Tumor development remains one of the major obstacles following organ transplantation. Immunosuppressive drugs such as cyclosporine and tacrolimus directly contribute to enhanced malignancy, whereas the influence of the novel compound mycophenolate mofetil (MMF) on tumor cell dissemination has not been explored. We therefore investigated the adhesion capacity of colon, pancreas, prostate and kidney carcinoma cell lines to endothelium, as well as their beta1 integrin expression profile before and after MMF treatment. Tumor cell adhesion to endothelial cell monolayers was evaluated in the presence of 0.1 and 1 μM MMF and compared to unstimulated controls. beta1 integrin analysis included alpha1beta1 (CD49a), alpha2beta1 (CD49b), alpha3beta1 (CD49c), alpha4beta1 (CD49d), alpha5beta1 (CD49e), and alpha6beta1 (CD49f) receptors, and was carried out by reverse transcriptase-polymerase chain reaction, confocal microscopy and flow cytometry. Adhesion of the colon carcinoma cell line HT-29 was strongly reduced in the presence of 0.1 μM MMF. This effect was accompanied by down-regulation of alpha3beta1 and alpha6beta1 surface expression and of alpha3beta1 and alpha6beta1 coding mRNA. Adhesion of the prostate tumor cell line DU-145 was blocked dose-dependently by MMF. In contrast to MMF's effects on HT-29 cells, MMF dose-dependently up-regulated alpha1beta1, alpha2beta1, alpha3beta1, and alpha5beta1 on DU-145 tumor cell membranes. We conclude that MMF possesses distinct anti-tumoral properties, particularly in colon and prostate carcinoma cells. Adhesion blockage of HT-29 cells was due to the loss of alpha3beta1 and alpha6beta1 surface expression, which might contribute to a reduced invasive behaviour of this tumor entity. The enhancement of integrin beta1 subtypes observed in DU-145 cells possibly causes re-differentiation towards a low-invasive phenotype

  17. Mycophenolate mofetil modulates adhesion receptors of the beta1 integrin family on tumor cells: impact on tumor recurrence and malignancy

    Directory of Open Access Journals (Sweden)

    Beecken Wolf-Dietrich

    2005-01-01

    Full Text Available Abstract Background Tumor development remains one of the major obstacles following organ transplantation. Immunosuppressive drugs such as cyclosporine and tacrolimus directly contribute to enhanced malignancy, whereas the influence of the novel compound mycophenolate mofetil (MMF on tumor cell dissemination has not been explored. We therefore investigated the adhesion capacity of colon, pancreas, prostate and kidney carcinoma cell lines to endothelium, as well as their beta1 integrin expression profile before and after MMF treatment. Methods Tumor cell adhesion to endothelial cell monolayers was evaluated in the presence of 0.1 and 1 μM MMF and compared to unstimulated controls. beta1 integrin analysis included alpha1beta1 (CD49a, alpha2beta1 (CD49b, alpha3beta1 (CD49c, alpha4beta1 (CD49d, alpha5beta1 (CD49e, and alpha6beta1 (CD49f receptors, and was carried out by reverse transcriptase-polymerase chain reaction, confocal microscopy and flow cytometry. Results Adhesion of the colon carcinoma cell line HT-29 was strongly reduced in the presence of 0.1 μM MMF. This effect was accompanied by down-regulation of alpha3beta1 and alpha6beta1 surface expression and of alpha3beta1 and alpha6beta1 coding mRNA. Adhesion of the prostate tumor cell line DU-145 was blocked dose-dependently by MMF. In contrast to MMF's effects on HT-29 cells, MMF dose-dependently up-regulated alpha1beta1, alpha2beta1, alpha3beta1, and alpha5beta1 on DU-145 tumor cell membranes. Conclusion We conclude that MMF possesses distinct anti-tumoral properties, particularly in colon and prostate carcinoma cells. Adhesion blockage of HT-29 cells was due to the loss of alpha3beta1 and alpha6beta1 surface expression, which might contribute to a reduced invasive behaviour of this tumor entity. The enhancement of integrin beta1 subtypes observed in DU-145 cells possibly causes re-differentiation towards a low-invasive phenotype.

  18. beta. -adrenergic receptor-mediated hepatic glycogenolysis is increased in aged male rats

    Energy Technology Data Exchange (ETDEWEB)

    Herring, P.A.; Graham, S.M.; Arinze, I.J.

    1986-03-05

    The effect of age on catecholamine-stimulated glycogenolysis was studied in isolated hepatocytes prepared from 3, 12, and 24 month-old rats. Glucose release was stimulated by epinephrine and norepinephrine, this was inhibited by phentolamine and prazosin. Isoproterenol (ISO) stimulated glycogenolysis only in cells from 24 month-old rats, this was blocked by propranolol. In liver plasma membranes, binding of (/sup 3/H)yohimbine (100-130 fmol/mg protein) did not change with age, whereas (/sup 3/H)prazosin binding decreased from 870 fmol/mg at 3 months to 435 fmol/mg at 12 months, but subsequently rose to 656 fmol/mg at 24 months. (/sup 125/I)Cyanopindolol binding increased from 8 fmol/mg at 3 months to 19 fmol/mg at 24 months. The proportion of ..beta..-receptors in the high affinity state increased from 28% at 3 months to 42% at 24 months. ISO stimulated adenylate cyclase at 24 months but not at 3 months. Basal, fluoride-, GTP-, and Gpp(NH)p-stimulated activities were 1.4- to 2.4-fold greater at 24 months than at 3 months. These results suggest an age-related increase in the sensitivity of adenylate cyclase to ..beta..-receptor stimulation.

  19. Glucocorticoids and beta-adrenergic-receptor agonists: their combined effect on fetal rabbit lung surfactant.

    Science.gov (United States)

    Ekelund, L; Enhorning, G

    1985-08-15

    In a previous study on pregnant rabbits (Am J Obstet Gynecol 1983; 147:437) we found that a prolonged infusion of the beta 2-adrenergic-receptor agonist terbutaline would first cause a release of fetal pulmonary surfactant, so that more was available in the airways. However, the airway fluid then contained less surfactant, indicating a depletion of stores. Since terbutaline is often used in high doses as a tocolytic agent, surfactant depletion could be a serious side effect. With further studies on rabbits, we wanted to test the hypothesis that with an accelerated surfactant synthesis, achieved with glucocorticoids, the increased release, evoked with the terbutaline, would never cause a depletion of the surfactant stores. Our results supported this hypothesis. Betamethasone, administered to the pregnant doe on the twenty-sixth and twenty-seventh days of gestation, 0.1 mg/kg, increased compliance of the fetal lungs, and more phospholipid phosphorus could be lavaged from the airways. These effects were further increased when, following steroid administration, the doe was infused with terbutaline. Depletion of the surfactant stores was never seen when betamethasone was given prior to the beta-adrenergic-receptor agonist. PMID:3839627

  20. Determination of beta-adrenergic receptor blocking pharmaceuticals in united states wastewater effluent

    International Nuclear Information System (INIS)

    This is the first report of beta-adrenergic receptor antagonist pharmaceuticals in United States wastewater effluent. - Beta adrenergic receptor antagonists (β-Blockers) are frequently prescribed medications in the United States and have been identified in European municipal wastewater effluent, however no studies to date have investigated these compounds in United States wastewater effluent. Municipal wastewater effluent was collected from treatment facilities in Mississippi, Texas, and New York to investigate the occurrence of metoprolol, nadolol, and propranolol. Propranolol was identified in all wastewater samples analyzed (n=34) at concentrations ≤1.9 μg/l. Metoprolol and nadolol were identified in ≥71% of the samples with concentrations of metoprolol ≤1.2 μg/l and nadolol ≤0.36 μg/l. Time course studies at both Mississippi plants and the Texas plant indicate that concentrations of propranolol, metoprolol, and nadolol remain relatively constant at each sampling period. This study indicates that β-Blockers are present in United States wastewater effluent in the ng/l to μg/l range

  1. N-methyl-D-aspartic acid receptor agonists

    DEFF Research Database (Denmark)

    Madsen, U; Frydenvang, Karla Andrea; Ebert, B;

    1996-01-01

    (R,S)-2-Amino-2-(3-hydroxy-5-methyl-4-isoxazolyl)acetic acid [(R,S)-AMAA, 4] is a potent and selective agonist at the N-methyl-D-aspartic acid (NMDA) subtype of excitatory amino acid receptors. Using the Ugi "four-component condensation" method, the two diastereomers (2R)- and (2S)-2-[3-(benzyloxy......) showed peak affinity for [3H]AMPA receptor sites (IC50 = 72 +/- 13 microM) and was shown to be a more potent inhibitor of [3H]CPP binding (IC50 = 3.7 +/- 1.5 microM) than (S)-AMAA (9) (IC50 = 61 +/- 6.4 microM). Neither enantiomer of AMAA affected [3H]kainic acid receptor binding significantly...

  2. Rapid effects of phytoestrogens on human colonic smooth muscle are mediated by oestrogen receptor beta.

    LENUS (Irish Health Repository)

    Hogan, A M

    2012-02-01

    Epidemiological studies have correlated consumption of dietary phytoestrogens with beneficial effects on colon, breast and prostate cancers. Genomic and non-genomic mechanisms are responsible for anti-carcinogenic effects but, until now, the effect on human colon was assumed to be passive and remote. No direct effect on human colonic smooth muscle has previously been described. Institutional research board approval was granted. Histologically normal colon was obtained from the proximal resection margin of colorectal carcinoma specimens. Circular smooth muscle strips were microdissected and suspended under 1g of tension in organ baths containing oxygenated Krebs solution at 37 degrees C. After an equilibration period, tissues were exposed to diarylpropionitrile (DPN) (ER beta agonist) and 1,3,5-tris(4-hydroxyphenyl)-4-propyl-1H-pyrazole (PPT) (ER alpha agonist) or to the synthetic phytoestrogen compounds genistein (n=8), daidzein (n=8), fisetin (n=8) and quercetin (n=8) in the presence or absence of fulvestrant (oestrogen receptor antagonist). Mechanism of action was investigated by inhibition of downstream pathways. The cholinergic agonist carbachol was used to induce contractile activity. Tension was recorded isometrically. Phytoestrogens inhibit carbachol-induced colonic contractility. In keeping with a non-genomic, rapid onset direct action, the effect was within minutes, reversible and similar to previously described actions of 17 beta oestradiol. No effect was seen in the presence of fulvestrant indicating receptor modulation. While the DPN exerted inhibitory effects, PPT did not. The effect appears to be reliant on a p38\\/mitogen activated protein kinase mediated induction of nitric oxide production in colonic smooth muscle. The present data set provides the first description of a direct effect of genistein, daidzein, fisetin and quercetin on human colonic smooth muscle. The presence of ER in colonic smooth muscle has been functionally proven and the beta

  3. Different expression of mu-opiate receptor in chronic and acute wounds and the effect of beta-endorphin on transforming growth factor beta type II receptor and cytokeratin 16 expression.

    Science.gov (United States)

    Bigliardi, P L; Sumanovski, L T; Büchner, S; Rufli, T; Bigliardi-Qi, M

    2003-01-01

    There is evidence that neuropeptides, especially the opiate receptor agonists, are involved in wound healing. We have previously observed that beta-endorphin, the endogenous ligand for the mu-opiate receptor, stimulates the expression of cytokeratin 16 in a dose-dependent manner in human skin organ cultures. Cytokeratin 16 is expressed in hyperproliferative epidermis such as psoriasis and wound healing. Therefore we were interested to study whether epidermal mu-opiate receptor expression is changed at the wound margins in acute and chronic wounds. Using classical and confocal microscopy, we were able to compare the expression level of mu-opiate receptors and the influence of beta-endorphin on transforming growth factor beta type II receptor in organ culture. Our results show indeed a significantly decreased expression of mu-opiate receptors on keratinocytes close to the wound margin of chronic wounds compared to acute wounds. Additionally beta-endorphin upregulates the expression of transforming growth factor beta type II receptor in human skin organ cultures. These results suggest a crucial role of opioid peptides not only in pain control but also in wound healing. Opioid peptides have already been used in animal models in treatment of wounds; they induce fibroblast proliferation and growth of capillaries, and accelerate the maturation of granulation tissue and the epithelization of the defect. Furthermore opioid peptides may fine-tune pain and the inflammatory response while healing takes place. This new knowledge could potentially be used to design new locally applied drugs to improve the healing of painful chronic wounds.

  4. Actinomyces tissue specificity may depend on differences in receptor specificity for GalNAc beta-containing glycoconjugates.

    OpenAIRE

    Strömberg, N.; Borén, T

    1992-01-01

    Actinomyces naeslundii 12104 and A. viscosus LY7 were compared for receptor specificities and adherence properties because these relate to their oral colonization sites. Both strains bind GalNAc beta-containing glycosphingolipids (GSLs) in a GalNAc beta 1-3Gal alpha Oethyl-sensitive fashion but differ with respect to the number of cells bound to GSLs and the effect of neighboring sugar groups on the binding. Their hemagglutination and saccharide inhibition profiles confirms the existence of t...

  5. Drug discovery opportunities and challenges at G protein coupled receptors for long chain free fatty acids

    Directory of Open Access Journals (Sweden)

    Nicholas D Holliday

    2012-01-01

    Full Text Available Discovery of G protein coupled receptors for long chain free fatty acids (FFAs, FFA1 (GPR40 and GPR120, has expanded our understanding of these nutrients as signalling molecules. These receptors have emerged as important sensors for FFA levels in the circulation or the gut lumen, based on evidence from in vitro and rodent models, and an increasing number of human studies. Here we consider their promise as therapeutic targets for metabolic disease, including type 2 diabetes and obesity. FFA1 directly mediates acute FFA-induced glucose-stimulated insulin secretion in pancreatic beta-cells, while GPR120 and FFA1 trigger release of incretins from intestinal endocrine cells, and so indirectly enhance insulin secretion and promote satiety. GPR120 signalling in adipocytes and macrophages also results in insulin sensitizing and beneficial anti-inflammatory effects. Drug discovery has focussed on agonists to replicate acute benefits of FFA receptor signalling, with promising early results for FFA1 agonists in man. Controversy surrounding chronic effects of FFA1 on beta-cells illustrates that long term benefits of antagonists also need exploring. It has proved challenging to generate highly selective potent ligands for FFA1 or GPR120 subtypes, given that both receptors have hydrophobic orthosteric binding sites, which are not completely defined and have modest ligand affinity. Structure activity relationships are also reliant on functional read outs, in the absence of robust binding assays to provide direct affinity estimates. Nevertheless synthetic ligands have already helped dissect specific contributions of FFA1 and GPR120 signalling from the many possible cellular effects of FFAs. Approaches including use of fluorescent ligand binding assays, and targeting allosteric receptor sites, may improve further preclinical ligand development at these receptors, to exploit their unique potential to target multiple facets of diabetes.

  6. Estrogen receptor beta participate in the regulation of metabolizm of extracellular matrix in estrogen alpha negative breast cancer.

    Science.gov (United States)

    Leśniewska, Monika; Miltyk, Wojciech; Swiatecka, Jolanta; Tomaszewska, Małgorzata; Kuźmicki, Mariusz; Pałka, Jerzy; Wołczyński, Sławomir

    2009-01-01

    The biology of breast cancer is closely releted to sex steroid hormones. Estrogen receptor beta is overexpressed in around 70% breast cancer cases, referrd to as "ER positive". Estrogens bind to estrogen receptor and stimulate the transcription of genes involved in control of cell proliferation. Moreover, estrogens may induce growth factors and components of extracellular matrix and interact with them in a complex manner. Extracellular matrix and integrins play an important role in cell functions and their aberrant expressions are implicated in breast cancer development, invasion and metastasis. ER beta is certainly associated with more differentiated tumors, while evidence of role of ER beta is controversial. The highly invasive breast cancer ER beta negative cell line MDA-MB 231 can be the model of exam the role of ER beta in breast cancer. The aim of this study was to examine the role of activation of ER beta on the metabolism of the extracellular matrix and the expression of beta-1 integrin in the breast cancer cell line MDA-MB 231. The cells were exposed on the estradiol, tamoxifen, raloxifen and genisteina in dose dependent concentrations. To determine the relative rate of collagen syntesis we measured the time-dependent reduction of collagen-bound radioactivity after pulse-chase labeling with [3 H] prolina by Peterkofsky methods. The expression of beta-1 integrin was determine by Western blot analysis. The activity of MMP2 and 9 were measured using gelatin zymography with an image analysis system. Our data suggest on the role of estrogen receptor beta on the metabolism of extracellular matrix in the breast cancer line MDA - MB 231. Estradiol and SERMs regulate the expression of ECM proteins: collagen, integrins and enhance activity of metaloproteinases 2 and 9. PMID:20067880

  7. Estrogen receptor beta participate in the regulation of metabolizm of extracellular matrix in estrogen alpha negative breast cancer.

    Directory of Open Access Journals (Sweden)

    Mariusz Kuźmicki

    2010-01-01

    Full Text Available The biology of breast cancer is closely releted to sex steroid hormones. Estrogen receptor beta is overexpressed in around 70% breast cancer cases, referrd to as "ER positive". Estrogens bind to estrogen receptor and stimulate the transcription of genes involved in control of cell proliferation. Moreover, estrogens may induce growth factors and components of extracellular matrix and interact with them in a complex manner. Extracellular matrix and integrins play an important role in cell functions and their aberrant expressions are implicated in breast cancer development, invasion and metastasis. ER beta is certainly associated with more differentiated tumors, while evidence of role of ER beta is controversial. The highly invasive breast cancer ER beta negative cell line MDA-MB 231 can be the model of exam the role of ER beta in breast cancer. The aim of this study was to examine the role of activation of ER beta on the metabolism of the extracellular matrix and the expression of beta-1 integrin in the breast cancer cell line MDA-MB 231. The cells were exposed on the estradiol, tamoxifen, raloxifen and genisteina in dose dependent concentrations. To determine the relative rate of collagen syntesis we measured the time-dependent reduction of collagen-bound radioactivity after pulse-chase labeling with [3 H] prolina by Peterkofsky methods. The expression of beta-1 integrin was determine by Western blot analysis. The activity of MMP2 and 9 were measured using gelatin zymography with an image analysis system. Our data suggest on the role of estrogen receptor beta on the metabolism of extracellular matrix in the breast cancer line MDA - MB 231. Estradiol and SERMs regulate the expression of ECM proteins: collagen, integrins and enhance activity of metaloproteinases 2 and 9.

  8. Signal transduction in human pancreatic cancer: roles of transforming growth factor beta, somatostatin receptors, and other signal intermediates.

    Science.gov (United States)

    Li, Min; Becnel, Lauren S; Li, Wei; Fisher, William E; Chen, Changyi; Yao, Qizhi

    2005-01-01

    Pancreatic cancer is a devastating disease because of the lack of early detection markers and effective treatments. It is the fourth leading cause of cancer-related death in western countries, including the United States. The mechanisms of pancreatic cancer progression remain unknown. Transforming growth factor beta (TGF-beta), a multifunctional cytokine, regulates cell growth and differentiation in healthy tissues, yet fails to do so in pancreatic cancer. Alterations of the TGF-beta and TGF-beta receptor/Smad signal transduction pathway have been implicated in pancreatic cancer. Furthermore, both the TGF-beta receptor and Smad proteins interact with a variety of cellular signal pathways, such as the somatostatin receptors (SSTRs), ERK1/2, and Wnt signal transduction cascades. This suggests that pancreatic cancer is a multi-gene-controlled malignancy and that effective treatments for pancreatic cancer should be aimed at multiple targets. In this review, we summarized the major signal intermediates involved in pancreatic cancer signal transduction pathways and specifically discussed how alterations in the regulatory functions of TGF-beta and Smad proteins allow for pancreatic carcinogenesis. PMID:16314822

  9. Bile acid derivatives as ligands of the farnesoid x receptor: molecular determinants for bile acid binding and receptor modulation.

    Science.gov (United States)

    Gioiello, Antimo; Cerra, Bruno; Mostarda, Serena; Guercini, Chiara; Pellicciari, Roberto; Macchiarulo, Antonio

    2014-01-01

    Bile acids are a peculiar class of steroidal compounds that never cease to amaze. From being simple detergents with a primary role in aiding the absorption of fats and fat-soluble vitamins, bile acids are now widely considered as crucial hormones endowed with genomic and non-genomic functions that are mediated by their interaction with several proteins including the nuclear receptor Farnesoid X Receptor (FXR). Taking advantages of the peculiar properties of bile acids in interacting with the FXR receptor, several biliary derivatives have been synthesized and tested as FXR ligands. The availability of these compounds has contributed to characterize the receptor from a structural, patho-physiological and therapeutic standpoint. Among these, obeticholic acid is a first-in-class FXR agonist that is demonstrating hepatoprotective effects upon FXR activation in patients with liver diseases such as primary biliary cirrhosis and nonalcoholic steatohepatitis. This review provides an historical overview of the rationale behind the discovery of obeticholic acid and chemical tools generated to depict the molecular features and bio-pharmacological relevance of the FXR receptor, as well as to summarize structure-activity relationships of bile acid-based FXR ligands so far reported. PMID:25388535

  10. Determination of urinary 18 beta-glycyrrhetinic acid by gas chromatography and its clinical application in man

    NARCIS (Netherlands)

    Guillaume, CPF; van der Molen, JC; Kerstens, MN; Dullaart, RPF; Wolthers, BG

    1999-01-01

    A sensitive and quantitative gas chromatographic assay for the determination of 18 beta-glycyrrhetinic acid (18 beta-GA), the main metabolite of glycyrrhizin after oral licorice consumption in human urine, has been developed and validated. For the extraction of 18 beta-GA from urine two Sep-Pak C-18

  11. [Interactions between dopamine receptor and NMDA/type A γ-aminobutyric acid receptors].

    Science.gov (United States)

    Chen, Hui-Ying; Wei, Ting-Jia; Weng, Jing-Jin; Qin, Jiang-Yuan; Huang, Xi; Su, Ji-Ping

    2016-04-25

    Type A γ-aminobutyric acid receptors (GABAAR) and N-methyl-D-aspartate receptors (NMDAR) are the major inhibitory and excitatory receptors in the central nervous system, respectively. Co-expression of the receptors in the synapse may lead to functional influence between receptors, namely receptor interaction. The interactions between GABAAR and NMDAR can be either positive or negative. However, the mechanisms of interaction between the two receptors remain poorly understood, and potential mechanisms include (1) through a second messenger; (2) by receptors trafficking; (3) by direct interaction; (4) by a third receptor-mediation. Dopamine is the most abundant catecholamine neurotransmitter in the brain, and its receptors, dopamine receptors (DR) can activate multiple signaling pathways. Earlier studies on the interaction between DR and GABAAR/NMDAR have shown some underlying mechanisms, suggesting that DR could mediate the interaction between GABAAR and NMDAR. This paper summarized some recent progresses in the studies of the interaction between DR and NMDAR/GABAAR, providing a further understanding on the interaction between NMDAR and GABAAR mediated by DR. PMID:27108906

  12. Mu-opiate receptor and Beta-endorphin expression in nerve endings and keratinocytes in human skin.

    Science.gov (United States)

    Bigliardi-Qi, M; Sumanovski, L T; Büchner, S; Rufli, T; Bigliardi, P L

    2004-01-01

    We have previously shown that human epidermal keratinocytes express a functionally active micro-opiate receptor, which adds a new dimension to the recently developed research in neuroimmunodermatology and neurogenic inflammation in skin diseases. Human keratinocytes specifically bind and also produce beta-endorphin, the endogenous micro-opiate receptor ligand. Using confocal imaging microscopy, we could now demonstrate that micro-opiate receptors are not only expressed in keratinocytes, but also on unmyelinated peripheral nerve fibers in the dermis and epidermis. Some of the peripheral nerve fibers also express the ligand beta-endorphin. The keratinocytes positive for beta-endorphin staining are clustered around the terminal ends of the unmyelinated nerve fibers. Therefore the opiate receptor system seems to be crucial in the direct communication between nerves and skin. The keratinocytes can influence the unmyelinated nerve fibers in the epidermis directly via secreting beta-endorphin. On the other hand, nerve fibers can also secrete beta-endorphin and influence the migration, differentiation and probably also the cytokine production pattern of keratinocytes.

  13. Oral Ascorbic Acid in Combination with Beta-Blockers Is More Effective than Beta-Blockers Alone in the Prevention of Atrial Fibrillation after Coronary Artery Bypass Grafting

    OpenAIRE

    Eslami, Masoud; Badkoubeh, Roya Sattarzadeh; Mousavi, Mehdi; Radmehr, Hassan; Salehi, Mehrdad; Tavakoli, Nafiseh; Avadi, Mohamad Reza

    2007-01-01

    Because adrenergic beta antagonists are not sufficient to prevent atrial fibrillation after coronary artery bypass grafting, this prospective, randomized trial was designed to evaluate the effects of ascorbic acid as an adjunct to β-blockers.

  14. Relationship between Expression of beta-catenin and VEGFs(VEGFA,VEGF-C),VEGF Receptors-2(VEGFR-2)in Medulloblastoma

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hong-mei; ZHANG Xiong; LI Yu; MI Can

    2008-01-01

    Objective:To investigate the expression of beta-catenin and VEGFs(VEGF-A,VEGF-C)and VEGF receptor-2(VEGFR-2)protein in medulloblastoma.Methods:Immunohistochemical staining with SP method Was conducted to determine the expression of beta-eatenin and VEGFs(VEGF-A,VEGF-C)and VEGFR-2 in 33 cases of medulloblastoma and 10 normal cerebellar tissues. Results:The expression rate of beta-catenin,and VEGFs (VEGF-A,VEGF-C)and VEGFR-2 in medulloblastoma were significantly higher than that in normal tissue.A significant positive correlation was found between beta-catenin and VEGFs(VEGF-A,VEGF-C)and VEGFR-2 protein in medulloblastoma. Conclusion:There was a correlation between beta-catenin and VEGFs(VEGF-A,VEGF-C)and VEGFR-2 in medulloblastoma,which may play a role in the pathogenesis and development of medulloblastoma.

  15. Mechanisms of transcriptional activation of the mouse claudin-5 promoter by estrogen receptor alpha and beta.

    Science.gov (United States)

    Burek, Malgorzata; Steinberg, Katrin; Förster, Carola Y

    2014-07-01

    Claudin-5 is an integral membrane protein and a critical component of endothelial tight junctions that control paracellular permeability. Claudin-5 is expressed at high levels in the brain vascular endothelium. Estrogens have multiple effects on vascular physiology and function. The biological actions of estrogens are mediated by two different estrogen receptor (ER) subtypes, ER alpha and ER beta. Estrogens have beneficial effects in several vascular disorders. Recently we have cloned and characterized a murine claudin-5 promoter and demonstrated 17beta-estradiol (E2)-mediated regulation of claudin-5 in brain and heart microvascular endothelium on promoter, mRNA and protein level. Sequence analysis revealed a putative estrogen response element (ERE) and a putative Sp1 transcription factor binding site in the claudin-5 promoter. The aim of the present study was to further characterize the estrogen-responsive elements of claudin-5 promoter. First, we introduced point mutations in ERE or Sp1 site in -500/+111 or in Sp1 site of -268/+111 claudin-5 promoter construct, respectively. Basal and E2-mediated transcriptional activation of mutated constructs was abrogated in the luciferase reporter gene assay. Next, we examined whether estrogen receptor subtypes bind to the claudin-5 promoter region. For this purpose we performed chromatin immunoprecipitation assays using anti-estrogen receptor antibodies and cellular lysates of E2-treated endothelial cells followed by quantitative PCR analysis. We show enrichment of claudin-5 promoter fragments containing the ERE- and Sp1-binding site in immunoprecipitates after E2 treatment. Finally, in a gel mobility shift assay, we demonstrated DNA-protein interaction of both ER subtypes at ERE. In summary, this study provides evidence that both a non-consensus ERE and a Sp1 site in the claudin-5 promoter are functional and necessary for the basal and E2-mediated activation of the promoter.

  16. Coregulation of calcium channels and beta-adrenergic receptors in cultured chick embryo ventricular cells

    International Nuclear Information System (INIS)

    To examine mechanisms whereby the abundance of functional Ca channels may be regulated in excitable tissue, Ca channel number was estimated by binding of the dihydropyridine (DHP) antagonist 3H (+)PN200-110 to monolayers of intact myocytes from chick embryo ventricle. Beta adrenergic receptor properties were studied in cultured myocytes using [3H]CGP12177, an antagonist ligand. Physiological correlates for alterations in DHP binding site number included 45Ca uptake and contractile response to (+)BAYk 8644, a specific L-type Ca channel activator. All binding and physiological determinations were performed in similar intact cell preparations under identical conditions. 4-h exposure to 1 microM isoproterenol reduced cell surface beta-adrenergic receptor number from 44 +/- 3 to 17 +/- 2 fmol/mg (P less than 0.05); DHP binding sites declined in number from 113 +/- 25 to 73 +/- 30 fmol/mg (P less than 0.03). When protein kinase A was activated by a non-receptor-dependent mechanism, DHP binding declined similarly to 68% of control. Exposure to diltiazem, a Ca channel antagonist, for 18-24 h had no effect on number of DHP binding sites. After 4-h isoproterenol exposure, 45Ca uptake stimulated by BAYk 8644 declined from 3.3 +/- 0.2 nmol/mg to 2.9 +/- 0.3 nmol/mg (P less than 0.01) and BAYk 8644-stimulated increase in amplitude of contraction declined from 168 +/- 7 to 134 +/- 11% (P = 0.02). Thus, elevation of [cAMP] in myocytes is associated with a time-dependent decline in Ca channel abundance as estimated by DHP binding and a decline in physiological responses that are in part dependent on abundance of Ca channels. Binding of a directly acting Ca channel antagonist for 18-24 h does not modulate the number of DHP binding sites

  17. RT-PCR and Northern blot analysis in search for a putative Paramecium beta-adrenergic receptor.

    Science.gov (United States)

    Płatek, A; Wiejak, J; Wyroba, E

    1999-01-01

    RT-PCR and Northern blot analysis were performed in order to search for a putative beta-adrenergic receptor (beta-AR) in Paramecium using several beta2-adrenergic-specific molecular probes. Under strictly defined RT-PCR conditions DNA species of expected molecular size about 360 bp were generated with the primers corresponding to the universal mammalian beta2-AR sequence tagged sites (located within the 4th and the 6th transmembrane regions of the receptor). This RT-PCR product hybridized in Southern blot analysis with the oligonucleotide probe designed to the highly conservative beta2-AR region involved in G-proteins interaction and located within the amplified region. Northern hybridization was performed on Paramecium total RNA and mRNA with human beta2-AR cDNA and two oligonucleotide probes: the first included Phe 290 involved in agonist binding (Strader et al., 1995) and the second was the backward RT-PCR primer. All these probes revealed the presence of about 2 kb mRNA which is consistent with the size of beta2-AR transcripts found in higher eukaryotes.

  18. The androgen 5alpha-dihydrotestosterone and its metabolite 5alpha-androstan-3beta, 17beta-diol inhibit the hypothalamo-pituitary-adrenal response to stress by acting through estrogen receptor beta-expressing neurons in the hypothalamus.

    Science.gov (United States)

    Lund, Trent D; Hinds, Laura R; Handa, Robert J

    2006-02-01

    Estrogen receptor beta (ERbeta) and androgen receptor (AR) are found in high levels within populations of neurons in the hypothalamus. To determine whether AR or ERbeta plays a role in regulating hypothalamo-pituitary-adrenal (HPA) axis function by direct action on these neurons, we examined the effects of central implants of 17beta-estradiol (E2), 5alpha-dihydrotestosterone (DHT), the DHT metabolite 5alpha-androstan-3beta, 17beta-diol (3beta-diol), and several ER subtype-selective agonists on the corticosterone and adrenocorticotropin (ACTH) response to immobilization stress. In addition, activation of neurons in the paraventricular nucleus (PVN) was monitored by examining c-fos mRNA expression. Pellets containing these compounds were stereotaxically implanted near the PVN of gonadectomized male rats. Seven days later, animals were killed directly from their home cage (nonstressed) or were restrained for 30 min (stressed) before they were killed. Compared with controls, E2 and the ERalpha-selective agonists moxestrol and propyl-pyrazole-triol significantly increased the stress induced release of corticosterone and ACTH. In contrast, central administration of DHT, 3beta-diol, and the ERbeta-selective compound diarylpropionitrile significantly decreased the corticosterone and ACTH response to immobilization. Cotreatment with the ER antagonist tamoxifen completely blocked the effects of 3beta-diol and partially blocked the effect of DHT, whereas the AR antagonist flutamide had no effect. Moreover, DHT, 3beta-diol, and diarylpropionitrile treatment significantly decreased restraint-induced c-fos mRNA expression in the PVN. Together, these studies indicate that the inhibitory effects of DHT on HPA axis activity may be in part mediated via its conversion to 3beta-diol and subsequent binding to ERbeta. PMID:16452668

  19. The profile of free amino acids in latent fingerprint of healthy and beta-thalassemic volunteers.

    Science.gov (United States)

    Khedr, Alaa

    2010-06-01

    The aim of the present work is to apply a non-invasive test, using thumb fingerprint residue analysis, for detection of beta-thalassemia (beta-Thal). The relative percentages of free amino acids (AA) in the latent fingerprint of beta-Thal patients and healthy subjects were compared. The sample included 24 beta-Thal patient and 24 healthy subjects, aged 5-10 years old. Twenty-three AA plus ammonia were analyzed by a sensitive high-performance liquid chromatographic method with fluorescence detection. The profile of AA was calculated based on the percentage of relative amount of each AA to serine (Ser) as it found to be the predominant peak. The statistical and chromatographic profiles of beta-Thal patients were characterized by significant decrease of ornithine, lysine, and zero tyrosine, with significant increase of ammonia, and proline. Other amino acids that exist in low ratios were estimated statistically for significance changes. The relative percentages of each AA of healthy subjects were approximately constant. For this reason, these mentioned AA were assigned as major fingerprint markers of beta-Thal.

  20. Ghrelin reduces hepatic mitochondrial fatty acid beta oxidation.

    Science.gov (United States)

    Rigault, C; Le Borgne, F; Georges, B; Demarquoy, J

    2007-04-01

    Ghrelin is a 28-amino-acid peptide secreted during starvation by gastric cells. Ghrelin physiologically induces food intake and seems to alter lipid and glucid metabolism in several tissues such as adipose tissue and liver. Liver has a key position in lipid metabolism as it allows the metabolic orientation of fatty acids between oxidation and esterification. We investigated the effects of peripheral ghrelin administration on 2 crucial parameters of fatty acid oxidation: the levocarnitine (L-carnitine)-dependent entry of the fatty acids in the mitochondria and the mitochondrial fatty acid oxidation. Ghrelin was either given to rats prior to the hepatocyte preparation and culture or used to treat hepatocytes prepared from control animals. Direct incubation of ghrelin to raw hepatocytes did not induce any change in the studied parameters. In hepatocytes prepared from 3 nmol ghrelin-treated rats, a 44% reduction of the mitochondrial fatty acid oxidation while no alteration of the L-carnitine-related parameters were observed. These results suggested (a) that ghrelin has no direct effect on liver, and (b) that when administrated to a whole organism, ghrelin may alter the lipid metabolism and the energy balance through a marked decrease in liver fatty acid oxidation. PMID:17556859

  1. Non-Acidic Free Fatty Acid Receptor 4 Agonists with Antidiabetic Activity

    DEFF Research Database (Denmark)

    Azevedo, Carlos M G; Watterson, Kenneth R; Wargent, Ed T;

    2016-01-01

    The free fatty acid receptor 4 (FFA4 or GPR120) has appeared as an interesting potential target for the treatment of metabolic disorders. At present, most FFA4 ligands are carboxylic acids that are assumed to mimic the endogenous long-chain fatty acid agonists. Here, we report preliminary structure...

  2. Positron emission tomography study on pancreatic somatostatin receptors in normal and diabetic rats with 68Ga-DOTA-octreotide: A potential PET tracer for beta cell mass measurement

    International Nuclear Information System (INIS)

    Highlights: •PET images showed high uptake of 68Ga-DOTA-octreotide in the normal pancreas. •68Ga-DOTA-octreotide specifically binds to somatostatin receptors in the pancreas. •The pancreatic uptake of 68Ga-DOTA-octreotide was decreased in the diabetic rats. •68Ga-DOTA-octreotide could be a candidate PET probe to measure the beta cell mass. -- Abstract: Diabetes mellitus (DM) is a metabolic disorder characterized by hyperglycemia, and the loss or dysfunction of pancreatic beta cells has been reported before the appearance of clinical symptoms and hyperglycemia. To evaluate beta cell mass (BCM) for improving the detection and treatment of DM at earlier stages, we focused on somatostatin receptors that are highly expressed in the pancreatic beta cells, and developed a positron emission tomography (PET) probe derived from octreotide, a metabolically stable somatostatin analog. Octreotide was conjugated with 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA), a chelating agent, and labeled with 68Gallium (68Ga). After intravenous injection of 68Ga-DOTA-octreotide, a 90-min emission scan of the abdomen was performed in normal and DM model rats. The PET studies showed that 68Ga-DOTA-octreotide radioactivity was highly accumulated in the pancreas of normal rats and that the pancreatic accumulation was significantly reduced in the rats administered with an excess amount of unlabeled octreotide or after treatment with streptozotocin, which was used for the chemical induction of DM in rats. These results were in good agreement with the ex vivo biodistribution data. These results indicated that the pancreatic accumulation of 68Ga-DOTA-octreotide represented specific binding to the somatostatin receptors and reflected BCM. Therefore, PET imaging with 68Ga-DOTA-octreotide could be a potential tool for evaluating BCM

  3. Direct Channeling of Retinoic Acid between Cellular Retinoic Acid-Binding Protein II and Retinoic Acid Receptor Sensitizes Mammary Carcinoma Cells to Retinoic Acid-Induced Growth Arrest

    OpenAIRE

    Budhu, Anuradha S.; Noy, Noa

    2002-01-01

    Cellular retinoic acid-binding protein II (CRABP-II) is an intracellular lipid-binding protein that associates with retinoic acid with a subnanomolar affinity. We previously showed that CRABP-II enhances the transcriptional activity of the nuclear receptor with which it shares a common ligand, namely, the retinoic acid receptor (RAR), and we suggested that it may act by delivering retinoic acid to this receptor. Here, the mechanisms underlying the effects of CRABP-II on the transcriptional ac...

  4. NR4A orphan nuclear receptors influence retinoic acid and docosahexaenoic acid signaling via up-regulation of fatty acid binding protein 5

    Energy Technology Data Exchange (ETDEWEB)

    Volakakis, Nikolaos; Joodmardi, Eliza [Ludwig Institute for Cancer Research Ltd., Box 240, S-17177 Stockholm (Sweden); Perlmann, Thomas, E-mail: thomas.perlmann@licr.ki.se [Ludwig Institute for Cancer Research Ltd., Box 240, S-17177 Stockholm (Sweden); The Department of Cell and Molecular Biology, Karolinska Institute, S-17177 Stockholm (Sweden)

    2009-12-25

    The orphan nuclear receptor (NR) Nurr1 is expressed in the developing and adult nervous system and is also induced as an immediate early gene in a variety of cell types. In silico analysis of human promoters identified fatty acid binding protein 5 (FABP5), a protein shown to enhance retinoic acid-mediated PPAR{beta}/{delta} signaling, as a potential Nurr1 target gene. Nurr1 has previously been implicated in retinoid signaling via its heterodimerization partner RXR. Since NRs are commonly involved in cross-regulatory control we decided to further investigate the regulatory relationship between Nurr1 and FABP5. FABP5 expression was up-regulated by Nurr1 and other NR4A NRs in HEK293 cells, and Nurr1 was shown to activate and bind to the FABP5 promoter, supporting that FABP5 is a direct downstream target of NR4A NRs. We also show that the RXR ligand docosahexaenoic acid (DHA) can induce nuclear translocation of FABP5. Moreover, via up-regulation of FABP5 Nurr1 can enhance retinoic acid-induced signaling of PPAR{beta}/{delta} and DHA-induced activation of RXR. We also found that other members of the NR4A orphan NRs can up-regulate FABP5. Thus, our findings suggest that NR4A orphan NRs can influence signaling events of other NRs via control of FABP5 expression levels.

  5. Reduced number of alpha- and beta-adrenergic receptors in the myocardium of rats exposed to tobacco smoke

    Energy Technology Data Exchange (ETDEWEB)

    Larue, D.; Kato, G.

    1981-04-09

    The concentration of alpha- and beta-adrenergic receptors--as measured by specific (/sup 3/H)WB-4101 and (-)-(/sup 3/H)dihydroalprenolol binding--was diminished by 60% below control values in the hearts of rats exposed to tobacco smoke. These changes in receptor numbers took place almost immediately after tobacco smoke exposure and were rapidly reversible after termination of the exposure. The dissociation constant, KD, for (/sup 3/H)WB-4101 was identical in exposed (KD . 0.34 +/- 0.09 nM) and control (KD . 0.35 +/- 0.07 nM) hearts but was significantly different in the case of (-)-(3H)dihydroalprenolol binding (exposed, KD . 2.83 +/- 0.30 mM vs. control KD . 5.22 +/- 0.61 nM). For beta-receptor binding there was no significant difference between exposed and control animals in the Ki values for (-)-epinephrine, (-)-norepinephrine, (-)-alprenolol, (+/-)-propranolol or timolol. (-)-Isoproterenol, however, was found to bind with lower affinity in exposed compared with control hearts. For alpha-receptor binding there was no significant difference between control and 'smoked' animals in the Ki values for (-)-epinephrine, (-0)-norepinephrine or phentolamine. The decrease in alpha- and beta-adrenergic receptor concentration may be related to the phenomenon of receptor desensitization resulting from a release of catecholamines in rats exposed to tobacco smoke.

  6. An LRP5 receptor with internal deletion in hyperparathyroid tumors with implications for deregulated WNT/beta-catenin signaling.

    Directory of Open Access Journals (Sweden)

    Peyman Björklund

    2007-11-01

    Full Text Available BACKGROUND: Hyperparathyroidism (HPT is a common endocrine disorder with incompletely understood etiology, characterized by enlarged hyperactive parathyroid glands and increased serum concentrations of parathyroid hormone and ionized calcium. We have recently reported activation of the Wnt signaling pathway by accumulation of beta-catenin in all analyzed parathyroid tumors from patients with primary HPT (pHPT and in hyperplastic parathyroid glands from patients with uremia secondary to HPT (sHPT. Mechanisms that may account for this activation have not been identified, except for a few cases of beta-catenin (CTNNB1 stabilizing mutation in pHPT tumors. METHODS AND FINDINGS: Reverse transcription PCR and Western blot analysis showed expression of an aberrantly spliced internally truncated WNT coreceptor low-density lipoprotein receptor-related protein 5 (LRP5 in 32 out of 37 pHPT tumors (86% and 20 out of 20 sHPT tumors (100%. Stabilizing mutation of CTNNB1 and expression of the internally truncated LRP5 receptor was mutually exclusive. Expression of the truncated LRP5 receptor was required to maintain the nonphosphorylated active beta-catenin level, transcription activity of beta-catenin, MYC expression, parathyroid cell growth in vitro, and parathyroid tumor growth in a xenograft severe combined immunodeficiency (SCID mouse model. WNT3 ligand and the internally truncated LRP5 receptor strongly activated transcription, and the internally truncated LRP5 receptor was insensitive to inhibition by DKK1. CONCLUSIONS: The internally truncated LRP5 receptor is strongly implicated in deregulated activation of the WNT/beta-catenin signaling pathway in hyperparathyroid tumors, and presents a potential target for therapeutic intervention.

  7. Genomic organization of the mouse peroxisome proliferator-activated receptor beta/delta gene

    DEFF Research Database (Denmark)

    Larsen, Leif K; Amri, Ez-Zoubir; Mandrup, Susanne;

    2002-01-01

    Peroxisome proliferator-activated receptor (PPAR) beta/delta is ubiquitously expressed, but the level of expression differs markedly between different cell types. In order to determine the molecular mechanisms governing PPARbeta/delta gene expression, we have isolated and characterized the mouse...... gene encoding PPARbeta/delta. The gene spans approx. 41 kb and comprises 11 exons of which the six exons located in the 3'-end of the gene are included in all transcripts. Primer-extension and 5'-rapid amplification of cDNA ends experiments revealed the presence of multiple transcription start points...... and splice variants, originating from the use of at least four different promoters. One of these transcription start points was found to be used predominantly in all tissues examined. Initiation from this major transcription start point gives rise to a transcript with a 548 nt 5'-untranslated leader...

  8. GABA{sub A} receptor beta 3 subunit gene is possibly paternally imprinted in humans

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-02-15

    As the gene for GABA{sub A} receptor beta 3 subunit (GABRB3) is encompassed by a small molecular deletion in chromosome 15q11-q13, which is the critical region for Angelman syndrome(AS), the GABRB3 gene could be a candidate gene for AS. The abnormal phenotype of AS is manifested only when the deletion is inherited from the mother, not from the father. Therefore, a candidate gene for AS should be paternally imprinted. Although it was reported that the GABRB3 gene was expressed equally from either the maternal or paternal chromosome in mouse brain (i.e., not imprinted), it is well known that imprinting shows tissue specificity, and it remains to be determined if all genes imprinted in the mouse are also imprinted in humans. 4 refs., 1 fig.

  9. Beta3 adrenergic receptor is involved in vascular injury in deoxycorticosterone acetate-salt hypertensive mice.

    Science.gov (United States)

    Sheng, Li-Juan; Ruan, Cheng-Chao; Ma, Yu; Chen, Dong-Rui; Kong, Ling-Ran; Zhu, Ding-Liang; Gao, Ping-Jin

    2016-03-01

    Beta3 adrenergic receptor (ADRB3) mediates vessel relaxation in the endothelium while it modulates lipolysis in the adipose tissue. However, the function and regulation mechanism of ADRB3 in the perivascular adipose tissue (PVAT), especially in hypertension, is still unclear. We show that ADRB3 protein is upregulated in the PVAT of deoxycorticosterone acetate-salt (DOCA-salt) hypertensive mice, with the characteristics of PVAT browning and increased uncoupling protein 1 (UCP1) expression. Inhibition of ADRB3 with selective antagonist SR59230A caused serious vascular injury in vivo, even though UCP1 expression was downregulated. ADRB3 protein was regulated by let-7b, which was decreased in the PVAT of the DOCA-salt group. These data reveal that ADRB3 in PVAT contributes to vascular function in the progression of hypertension. PMID:26910302

  10. The effects of beta acids from hops (Humulus lupulus L.)on mortality of Varroa destructor (Acari: Varroidae)

    Science.gov (United States)

    Beta acids from hop plants (Humulus lupulus L.) reduce feeding and oviposition behaviors and increase mortality in certain phytophagous mites. These compounds were tested for their effects on Varroa destructor (Anderson and Trueman) mortality. The effects of hops beta acids (HBA) on honey bee (Apis ...

  11. A Multicomponent UV Analysis of ["alpha"]- and ["beta"]-Acids in Hops

    Science.gov (United States)

    Egts, Haley; Durben, Dan J.; Dixson, John A.; Zehfus, Micheal H.

    2012-01-01

    A method is presented for the determination of ["alpha"]- and ["beta"]-acids (humulones and lupulones) in a hops sample using a multicomponent UV spectroscopic analysis of a methanolic hop extract. When compared with standard methods, this lab can be considered "greener" because it uses smaller volumes of safer solvents (methanol instead of…

  12. Hepatic fat is not associated with beta-cell function or postprandial free fatty acid response

    NARCIS (Netherlands)

    Rijkelijkhuizen, J.M.; Doesburg, T.; Girman, C.J.; Mari, A.; Rhodes, T.; Gastaldelli, A.; Nijpels, M.G.A.A.M.; Dekker, J.M.

    2009-01-01

    We evaluated the association of hepatic fat with beta-cell function estimated from the oral glucose tolerance test. In addition, we tested the hypothesis that postprandial free fatty acid (FFA) suppression after a meal tolerance test (MTT) is linked to hepatic fat. Individuals with normal glucose me

  13. AVPV neurons containing estrogen receptor-beta in adult male rats are influenced by soy isoflavones

    Directory of Open Access Journals (Sweden)

    Bu Lihong

    2007-02-01

    Full Text Available Abstract Background Isoflavones, the most abundant phytoestrogens in soy foods, are structurally similar to 17beta-estradiol. It is known that 17beta-estradiol induces apoptosis in anteroventral periventricular nucleus (AVPV in rat brain. Also, there is evidence that consumption of soy isoflavones reduces the volume of AVPV in male rats. Therefore, in this study, we examined the influence of dietary soy isoflavones on apoptosis in AVPV of 150 day-old male rats fed either a soy isoflavone-free diet (Phyto-free or a soy isoflavone-rich diet (Phyto-600. Results The occurrence of apoptosis in AVPV was examined by TUNEL staining. The incidence of apoptosis was about 10 times higher in the Phyto-600 group (33.1 ± 1.7% than in the Phyto-free group (3.6 ± 1.0%. Furthermore, these apoptotic cells were identified as neurons by dual immunofluorescent staining of GFAP and NeuN as markers of astrocytes and neurons, respectively. Then the dopaminergic neurons in AVPV were detected by immunohistochemistry staining of tyrosine hydroxylase (TH. No significant difference in the number of TH neurons was observed between the diet treatment groups. When estrogen receptor (ER alpha and beta were examined by immunohistochemistry, we observed a 22% reduction of ERbeta-positive cell numbers in AVPV with consumption of soy isoflavones, whereas no significant change in ERalpha-positive cell numbers was detected. Furthermore, almost all the apoptotic cells were ERbeta-immunoreactive (ir, but not ERalpha-ir. Last, subcutaneous injections of equol (a major isoflavone metabolite that accounts for approximately 70–90% of the total circulating plasma isoflavone levels did not alter the volume of AVPV in adult male rats. Conclusion In summary, these findings provide direct evidence that consumption of soy isoflavones, but not the exposure to equol, influences the loss of ERbeta-containing neurons in male AVPV.

  14. In vivo occupancy of female rat brain estrogen receptors by 17beta-estradiol and tamoxifen.

    Science.gov (United States)

    Pareto, D; Alvarado, M; Hanrahan, S M; Biegon, A

    2004-11-01

    Estrogens or antiestrogens are currently used by millions of women, but the interaction of these hormonal agents with brain estrogen receptors (ER) in vivo has not been characterized to date. Our goal was to assess, in vivo, the extent and regional distribution of brain ER occupancy in rats chronically exposed to 17beta-estradiol (E(2)) or tamoxifen (TAM). For that purpose, female ovariectomized Sprague-Dawley rats were implanted with subcutaneous pellets containing either placebo (OVX), E(2), or TAM for 3 weeks. ER occupancy in grossly dissected regions was quantified with 16alpha-[(18)F]fluoroestradiol ([(18)F]FES). Both E(2) and TAM produced significant decreases in radioligand uptake in the brain although the effect of E(2) was larger and more widespread than the effect of TAM. Detailed regional analysis of the interaction was then undertaken using a radioiodinated ligand, 11beta-methoxy-16alpha-[(125)I]iodo-estradiol ([(125)I]MIE(2)), and quantitative ex vivo autoradiography. E(2) treatment resulted in near-complete (86.6 +/- 17.5%) inhibition of radioligand accumulation throughout the brain, while ER occupancy in the TAM group showed a marked regional distribution such that percentage inhibition ranged from 40.5 +/- 15.6 in the ventrolateral part of the ventromedial hypothalamic nucleus to 84.6 +/- 4.5 in the cortical amygdala. These results show that exposure to pharmacologically relevant levels of TAM produces a variable, region-specific pattern of brain ER occupancy, which may be influenced by the regional proportion of ER receptor subtypes. These findings may partially explain the highly variable and region-specific effects observed in neurochemical, metabolic, and functional studies of the effects of TAM in the brain of experimental animals as well as human subjects.

  15. Obeticholic acid, a synthetic bile acid agonist of the farnesoid X receptor, attenuates experimental autoimmune encephalomyelitis

    OpenAIRE

    Peggy P. Ho; Steinman, Lawrence

    2016-01-01

    Bile acids bind to the nuclear hormone receptor, farnesoid X receptor (FXR). This bile acid–FXR interaction regulates bile acid synthesis, transport, and cholesterol metabolism. Recently, drugs targeting FXR activation have been reported to treat both liver and intestinal inflammatory diseases in both animal models and human clinical trials. Experimental autoimmune encephalomyelitis (EAE) is an inflammatory demyelinating disease of the central nervous system and serves as an animal model for ...

  16. Nuclear orphan receptor TLX affects gene expression, proliferation and cell apoptosis in beta cells.

    Science.gov (United States)

    Shi, Xiaoli; Xiong, Xiaokan; Dai, Zhe; Deng, Haohua; Sun, Li; Hu, Xuemei; Zhou, Feng; Xu, Yancheng

    Nuclear orphan receptor TLX is an essential regulator of the growth of neural stem cells. However, its exact function in pancreatic islet cells is still unknown. In the present study, gene expression profiling analysis revealed that overexpression of TLX in beta cell line MIN6 causes suppression of 176 genes and upregulation of 49 genes, including a cadre of cell cycle, cell proliferation and cell death control genes, such as Btg2, Ddit3 and Gadd45a. We next examined the effects of TLX overexpression on proliferation, apoptosis and insulin secretion in MIN6 cells. Proliferation analysis using EdU assay showed that overexpression of TLX increased percentage of EdU-positive cells. Cell cycle and apoptosis analysis revealed that overexpression of TLX in MIN6 cells resulted in higher percentage of cells exiting G1 into S-phase, and a 58.8% decrease of cell apoptosis induced by 0.5 mM palmitate. Moreover, TLX overexpression did not cause impairment of insulin secretion. Together, we conclude that TLX is among factors capable of controlling beta cell proliferation and survival, which may serve as a target for the development of novel therapies for diabetes.

  17. INTERACTION OF PAH-RELATED COMPOUNDS WITH THE ALPHA AND BETA ISOFORMS OF ESTROGEN RECEPTOR. (R826192)

    Science.gov (United States)

    The ability of several 4- and 5-ring polycyclic aromatic hydrocarbons (PAHs), heterocyclic PAHs, and their monohydroxy derivatives to interact with the estrogen receptor (ER) alpha and beta isoforms was examined. Only compounds possessing a hydroxyl group were able to compete wit...

  18. Vertebral Artery Aneurysm Mimicking as Left Subclavian Artery Aneurysm in a Patient with Transforming Growth Factor Beta Receptor II Mutation.

    Science.gov (United States)

    Afifi, Rana O; Dhillon, Baltej Singh; Sandhu, Harleen K; Charlton-Ouw, Kristofer M; Estrera, Anthony L; Azizzadeh, Ali

    2015-10-01

    We report successful endovascular repair of a left vertebral artery aneurysm in a patient with transforming growth factor beta receptor II mutation. The patient was initially diagnosed with a left subclavian artery aneurysm on computed tomography angiography. The patient consented to publication of this report.

  19. Polymorphisms of innate pattern recognition receptors, response to interferon-beta and development of neutralizing antibodies in multiple sclerosis patients

    DEFF Research Database (Denmark)

    Enevold, Christian; Oturai, Annette Bang; Sørensen, Per Soelberg;

    2010-01-01

    Interferon-beta therapy of patients with relapsing-remitting multiple sclerosis involves repeated 'immunizations' with exogenous protein solutions. Innate pattern recognition receptors play an important role in immune responses towards foreign substances and may thus be related to treatment outcome....

  20. Disappearance of beta(2)-adrenergic receptors on astrocytes in canine distemper encephalitis : possible implications for the pathogenesis of multiple sclerosis

    NARCIS (Netherlands)

    De Keyser, J; Wilczak, N; Zurbriggen, A

    2001-01-01

    It has been reported that astrocytes in the white matter of patients with multiple sclerosis (MS) lack beta (2)-adrenergic receptors. This abnormality might explain why astrocytes in active MS plaques aberrantly express major histocompatibility (MHC) class II molecules, which play an important role

  1. How Can 1+1=3? beta(2)-Adrenergic and Glucocorticoid Receptor Agonist Synergism in Obstructive Airway Diseases

    NARCIS (Netherlands)

    Schmidt, Martina; Michel, Martin C.

    2011-01-01

    For a long time it was believed that beta(2)-adrenergic receptor agonists used in the treatment of obstructive airway diseases worked primarily on airway smooth muscle cells, causing relaxation, whereas glucocorticoids primarily improved airway function via their anti-inflammatory action, indicating

  2. Platelet-Derived Growth Factor Receptor Beta Serum Concentrations during First-Line Therapy in Ovarian Cancer

    NARCIS (Netherlands)

    Mathey, Sabrina; Graeser, Monika Karla; Eulenburg, Christine Zu; Woelber, Linn; Trillsch, Fabian; Jaenicke, Fritz; Mueller, Volkmar; Milde-Langosch, Karin; Mahner, Sven

    2013-01-01

    Objectives: Angiogenesis plays an important role in ovarian cancer. The interaction of platelet-derived growth factor receptor-beta (PDGFR-P) with vascular endothelial growth factor (VEGF) in the process of angiogenesis may represent an essential feature in the progression of the disease. Methods: P

  3. Selective suppression of chemokine receptor CXCR3 expression by interferon-beta1a in multiple sclerosis

    DEFF Research Database (Denmark)

    Sørensen, Torben Lykke; Sellebjerg, F

    2002-01-01

    We studied the expression of chemokine receptors CCR1, CCR2, CCR3, CCR5, and CXCR3 on CD4 and CD8 positive T cells, and on CD14 positive monocytes in blood from 10 patients with relapsing-remitting multiple sclerosis (MS) at initiation of interferon (IFN)-beta treatment, after 1 month and after 3...

  4. Family-based association analysis of beta(2)-adrenergic receptor polymorphisms in the Childhood Asthma Management Program

    NARCIS (Netherlands)

    Silverman, EK; Kwiatkowski, DJ; Sylvia, JS; Lazarus, R; Drazen, JM; Lange, C; Laird, NM; Weiss, ST

    2003-01-01

    Background: beta(2)-Adrenergic receptor (B2AR) polymorphisms have been associated with a variety of asthma-related phenotypes, but association results have been inconsistent across different studies. Objective: We sought to apply family-based association methods to individual single nucleotide polym

  5. Internalization of the human CRF receptor 1 is independent of classical phosphorylation sites and of beta-arrestin 1 recruitment

    DEFF Research Database (Denmark)

    Rasmussen, Trine N; Novak, Ivana; Nielsen, Søren M

    2004-01-01

    . In the present study, agonist-induced internalization of CRFR1 in HEK293 cells was visualized by confocal microscopy and quantified using the radioligand 125I-labelled sauvagine. Recruitment of beta-arrestin 1 in response to receptor activation was demonstrated by confocal microscopy. The extent of 125I...

  6. Enzymatic synthesis of enantiopure alpha- and beta-amino acids by phenylalanine aminomutase-catalysed amination of cinnamic acid derivatives.

    Science.gov (United States)

    Wu, Bian; Szymanski, Wiktor; Wietzes, Piet; de Wildeman, Stefaan; Poelarends, Gerrit J; Feringa, Ben L; Janssen, Dick B

    2009-01-26

    The phenylalanine aminomutase (PAM) from Taxus chinensis catalyses the conversion of alpha-phenylalanine to beta-phenylalanine, an important step in the biosynthesis of the N-benzoyl phenylisoserinoyl side-chain of the anticancer drug taxol. Mechanistic studies on PAM have suggested that (E)-cinnamic acid is an intermediate in the mutase reaction and that it can be released from the enzyme's active site. Here we describe a novel synthetic strategy that is based on the finding that ring-substituted (E)-cinnamic acids can serve as a substrate in PAM-catalysed ammonia addition reactions for the biocatalytic production of several important beta-amino acids. The enzyme has a broad substrate range and a high enantioselectivity with cinnamic acid derivatives; this allows the synthesis of several non-natural aromatic alpha- and beta-amino acids in excellent enantiomeric excess (ee >99 %). The internal 5-methylene-3,5-dihydroimidazol-4-one (MIO) cofactor is essential for the PAM-catalysed amination reactions. The regioselectivity of amination reactions was influenced by the nature of the ring substituent.

  7. The effect of the creatine analogue beta-guanidinopropionic acid on energy metabolism: a systematic review.

    Directory of Open Access Journals (Sweden)

    Inge Oudman

    Full Text Available BACKGROUND: Creatine kinase plays a key role in cellular energy transport. The enzyme transfers high-energy phosphoryl groups from mitochondria to subcellular sites of ATP hydrolysis, where it buffers ADP concentration by catalyzing the reversible transfer of the high-energy phosphate moiety (P between creatine and ADP. Cellular creatine uptake is competitively inhibited by beta-guanidinopropionic acid. This substance is marked as safe for human use, but the effects are unclear. Therefore, we systematically reviewed the effect of beta-guanidinopropionic acid on energy metabolism and function of tissues with high energy demands. METHODS: We performed a systematic review and searched the electronic databases Pubmed, EMBASE, the Cochrane Library, and LILACS from their inception through March 2011. Furthermore, we searched the internet and explored references from textbooks and reviews. RESULTS: After applying the inclusion criteria, we retrieved 131 publications, mainly considering the effect of chronic oral administration of beta-guanidinopropionic acid (0.5 to 3.5% on skeletal muscle, the cardiovascular system, and brain tissue in animals. Beta-guanidinopropionic acid decreased intracellular creatine and phosphocreatine in all tissues studied. In skeletal muscle, this effect induced a shift from glycolytic to oxidative metabolism, increased cellular glucose uptake and increased fatigue tolerance. In heart tissue this shift to mitochondrial metabolism was less pronounced. Myocardial contractility was modestly reduced, including a decreased ventricular developed pressure, albeit with unchanged cardiac output. In brain tissue adaptations in energy metabolism resulted in enhanced ATP stability and survival during hypoxia. CONCLUSION: Chronic beta-guanidinopropionic acid increases fatigue tolerance of skeletal muscle and survival during ischaemia in animal studies, with modestly reduced myocardial contractility. Because it is marked as safe for human

  8. High-resolution crystal structure of an engineered human beta2-adrenergic G protein-coupled receptor

    DEFF Research Database (Denmark)

    Cherezov, Vadim; Rosenbaum, Daniel M; Hanson, Michael A;

    2007-01-01

    Heterotrimeric guanine nucleotide-binding protein (G protein)-coupled receptors constitute the largest family of eukaryotic signal transduction proteins that communicate across the membrane. We report the crystal structure of a human beta2-adrenergic receptor-T4 lysozyme fusion protein bound...... to the partial inverse agonist carazolol at 2.4 angstrom resolution. The structure provides a high-resolution view of a human G protein-coupled receptor bound to a diffusible ligand. Ligand-binding site accessibility is enabled by the second extracellular loop, which is held out of the binding cavity by a pair...

  9. Multifunctional acid formation from the gas-phase ozonolysis of beta-pinene.

    Science.gov (United States)

    Ma, Yan; Marston, George

    2008-10-28

    The gas-phase ozonolysis of beta-pinene was studied in static chamber experiments, using gas chromatography coupled to mass spectrometric and flame ionisation detection to separate and detect products. A range of multifunctional organic acids-including pinic acid, norpinic acid, pinalic-3-acid, pinalic-4-acid, norpinalic acid and OH-pinalic acid-were identified in the condensed phase after derivatisation. Formation yields for these products under systematically varying reaction conditions (by adding different OH radical scavengers and Criegee intermediate scavengers) were investigated and compared with those observed from alpha-pinene ozonolysis, allowing detailed information on product formation mechanisms to be elucidated. In addition, branching ratios for the initial steps of the reaction were inferred from quantitative measurements of primary carbonyl formation. Atmospheric implications of this work are discussed.

  10. Phenylalanine Aminomutase-Catalyzed Addition of Ammonia to Substituted Cinnamic Acids : a Route to Enantiopure alpha- and beta-Amino Acids

    NARCIS (Netherlands)

    Szymanski, Wiktor; Wu, Bian; Weiner, Barbara; Wildeman, Stefaan de; Feringa, Ben L.; Janssen, Dick B.

    2009-01-01

    An approach is described for the synthesis of aromatic alpha- and beta-amino acids that Uses phenylalanine aminomutase to catalyze a highly enantioselective addition of ammonia to substituted cinnamic acids. The reaction has a broad scope and yields Substituted alpha- and beta-phenylalanines with ex

  11. Bile acid receptors and nonalcoholic fatty liver disease

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    With the high prevalence of obesity, diabetes, and otherfeatures of the metabolic syndrome in United States,nonalcoholic fatty liver disease (NAFLD) has inevitablybecome a very prevalent chronic liver disease and isnow emerging as one of the leading indications for livertransplantation. Insulin resistance and derangementof lipid metabolism, accompanied by activation ofthe pro-inflammatory response and fibrogenesis, areessential pathways in the development of the moreclinically significant form of NAFLD, known as nonalcoholicsteatohepatitis (NASH). Recent advances inthe functional characterization of bile acid receptors,such as farnesoid X receptor (FXR) and transmembraneG protein-coupled receptor (TGR) 5, have providedfurther insight in the pathophysiology of NASH andhave led to the development of potential therapeutictargets for NAFLD and NASH. Beyond maintaining bileacid metabolism, FXR and TGR5 also regulate lipidmetabolism, maintain glucose homeostasis, increaseenergy expenditure, and ameliorate hepatic inflammation.These intriguing features have been exploitedto develop bile acid analogues to target pathways inNAFLD and NASH pathogenesis. This review providesa brief overview of the pathogenesis of NAFLD andNASH, and then delves into the biological functions ofbile acid receptors, particularly with respect to NASHpathogenesis, with a description of the associatedexperimental data, and, finally, we discuss the prospectsof bile acid analogues in the treatment of NAFLD andNASH.

  12. High affinity retinoic acid receptor antagonists: analogs of AGN 193109.

    Science.gov (United States)

    Johnson, A T; Wang, L; Gillett, S J; Chandraratna, R A

    1999-02-22

    A series of high affinity retinoic acid receptor (RAR) antagonists were prepared based upon the known antagonist AGN 193109 (2). Introduction of various phenyl groups revealed a preference for substitution at the para-position relative to the meta-site. Antagonists with the highest affinities for the RARs possessed hydrophobic groups, however, the presence of polar functionality was also well tolerated.

  13. Study of binding glycyrrhetic acid to AT1 receptor

    Institute of Scientific and Technical Information of China (English)

    ZHANG; Fengyun; (张凤云); YUE; Baozhen; (岳保珍); HE; Shipeng; (贺师鹏)

    2003-01-01

    To analyze the binding of glycyrrhetic acid (GA) to angiotensin II type I (AT1) receptor and to explore the mechanisms underlying the binding, primary cell culture of rat vascular smooth muscle cell (VSMC), radioactive ligand-receptor binding assay, lascer confocal scanning microscope (LCSM), Northern blot, 3H-TdR incorporation DNA assay were used in this study. The results suggest that specific binding of GA to AT1 receptor (IC50 value was 35.0 μmol/L) increases intracellular [Ca2+]i of VSMC, activates transcription factor c-myc and promotes the proliferation of VSMC, therefore GA was probably an agonist of AT1 receptor, providing a new target for GA's pharmaceutical effects.

  14. Retinoic Acid-mediated Nuclear Receptor Activation and Hepatocyte Proliferation

    Science.gov (United States)

    Bushue, Nathan; Wan, Yu-Jui Yvonne

    2016-01-01

    Due to their well-known differentiation and apoptosis-inducing abilities, retinoic acid (RA) and its analogs have strong anti-cancer efficacy in human cancers. However, in vivo RA is a liver mitogen. While speculation has persisted that RA-mediated signaling is likely involved in hepatocyte proliferation during liver regeneration, direct evidence is still required. Findings in support of this proposition include observations that a release of retinyl palmitate (the precursor of RA) occurs in liver stellate cells following liver injury. Nevertheless, the biological action of this released vitamin A is virtually unknown. More likely is that the released vitamin A is converted to RA, the biological form, and then bound to a specific receptor (retinoid x receptor; RXRα), which is most abundantly expressed in the liver. Considering the mitogenic effects of RA, the RA-activated RXRα would likely then influence hepatocyte proliferation and liver tissue repair. At present, the mechanism by which RA stimulates hepatocyte proliferation is largely unknown. This review summarizes the activation of nuclear receptors (peroxisome proliferator activated receptor-α, pregnane x receptor, constitutive androstane receptor, and farnesoid x receptor) in an RXRα dependent manner to induce hepatocyte proliferation, providing a link between RA and its proliferative role.

  15. Platelet-derived growth factor receptor beta is critical for zebrafish intersegmental vessel formation.

    Directory of Open Access Journals (Sweden)

    Katie M Wiens

    Full Text Available BACKGROUND: Platelet-derived growth factor receptor beta (PDGFRbeta is a tyrosine kinase receptor known to affect vascular development. The zebrafish is an excellent model to study specific regulators of vascular development, yet the role of PDGF signaling has not been determined in early zebrafish embryos. Furthermore, vascular mural cells, in which PDGFRbeta functions cell autonomously in other systems, have not been identified in zebrafish embryos younger than 72 hours post fertilization. METHODOLOGY/PRINCIPAL FINDINGS: In order to investigate the role of PDGFRbeta in zebrafish vascular development, we cloned the highly conserved zebrafish homolog of PDGFRbeta. We found that pdgfrbeta is expressed in the hypochord, a developmental structure that is immediately dorsal to the dorsal aorta and potentially regulates blood vessel development in the zebrafish. Using a PDGFR tyrosine kinase inhibitor, a morpholino oligonucleotide specific to PDGFRbeta, and a dominant negative PDGFRbeta transgenic line, we found that PDGFRbeta is necessary for angiogenesis of the intersegmental vessels. SIGNIFICANCE/CONCLUSION: Our data provide the first evidence that PDGFRbeta signaling is required for zebrafish angiogenesis. We propose a novel mechanism for zebrafish PDGFRbeta signaling that regulates vascular angiogenesis in the absence of mural cells.

  16. Oxidative dehydration of glycerol to acrylic acid over vanadium-impregnated zeolite beta

    International Nuclear Information System (INIS)

    The oxidative dehydration of glycerol to acrylic acid was studied over vanadium-impregnated zeolite Beta. Catalysts were prepared by wet impregnation of ammonium metavanadate over ammonium-exchanged zeolite Beta, followed by air calcination at 823 K. Impregnation reduced the specific surface area, but did not significantly affected the acidity (Bronsted and Lewis) of the zeolites. The catalytic evaluation was carried out in a fixed bed flow reactor using air as the carrier and injecting glycerol by means of a syringe pump. Acrolein was the main product, with acetaldehyde and hydroxy-acetone (acetol) being also formed. Acrylic acid was formed with approximately 25% selectivity at 548 K over the impregnated zeolites. The result can be explained by XPS (X-ray photoelectron spectroscopy) measurements, which indicated a good dispersion of the vanadium inside the pores. (author)

  17. Oxidative dehydration of glycerol to acrylic acid over vanadium-impregnated zeolite beta

    Energy Technology Data Exchange (ETDEWEB)

    Pestana, Carolina F.M.; Guerra, Antonio C.O.; Turci, Cassia C. [Universidade Federal do Rio de Janeiro, RJ (Brazil). Inst. de Quimica; Ferreira, Glaucio B. [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Inst. de Quimica; Mota, Claudio J.A., E-mail: cmota@iq.ufrj.br [INCT Energia e Ambiente, Universidade Federal do Rio de Janeiro, RJ (Brazil)

    2013-01-15

    The oxidative dehydration of glycerol to acrylic acid was studied over vanadium-impregnated zeolite Beta. Catalysts were prepared by wet impregnation of ammonium metavanadate over ammonium-exchanged zeolite Beta, followed by air calcination at 823 K. Impregnation reduced the specific surface area, but did not significantly affected the acidity (Bronsted and Lewis) of the zeolites. The catalytic evaluation was carried out in a fixed bed flow reactor using air as the carrier and injecting glycerol by means of a syringe pump. Acrolein was the main product, with acetaldehyde and hydroxy-acetone (acetol) being also formed. Acrylic acid was formed with approximately 25% selectivity at 548 K over the impregnated zeolites. The result can be explained by XPS (X-ray photoelectron spectroscopy) measurements, which indicated a good dispersion of the vanadium inside the pores. (author)

  18. Molecular basis for amino acid sensing by family C G-protein-coupled receptors

    DEFF Research Database (Denmark)

    Wellendorph, Petrine; Bräuner-Osborne, Hans

    2009-01-01

    -alpha;-amino acid receptor G-protein-coupled receptor family C, group 6, subtype A (GPRC6A) and seven orphan receptors. Aside from the orphan receptors, the family C GPCRs are dimeric receptors characterized by a large extracellular Venus flytrap domain which bind the endogenous agonists. Except from the GABA(B1......-2) and T1R2-3 receptor, all receptors are either activated or positively modulated by amino acids. In this review, we outline mutational, biophysical and structural studies which have elucidated the interaction of the amino acids with the Venus flytrap domains, molecular mechanisms of receptor selectivity...

  19. Generation of an estrogen receptor beta-iCre knock-in mouse.

    Science.gov (United States)

    Cacioppo, Joseph A; Koo, Yongbum; Lin, Po-Ching Patrick; Osmulski, Sarah A; Ko, Chunjoo D; Ko, CheMyong

    2016-01-01

    A novel knock-in mouse that expresses codon-improved Cre recombinase (iCre) under regulation of the estrogen receptor beta (Esr2) promoter was developed for conditional deletion of genes and for the spatial and/or temporal localization of Esr2 expression. ESR2 is one of two classical nuclear estrogen receptors and displays a spatiotemporal expression pattern and functions that are different from the other estrogen receptor, ESR1. A cassette was constructed that contained iCre, a polyadenylation sequence, and a neomycin selection marker. This construct was used to insert iCre in front of the endogenous start codon of the Esr2 gene of a C57BL/6J embryonic stem cell line via homologous recombination. Resulting Esr2-iCre mice were bred with ROSA26-lacZ and Ai9-RFP reporter mice to visualize cells of functional iCre expression. Strong expression was observed in the ovary, the pituitary, the interstitium of the testes, the head and tail but not body of the epididymis, skeletal muscle, the coagulation gland (anterior prostate), the lung, and the preputial gland. Additional diffuse or patchy expression was observed in the cerebrum, the hypothalamus, the heart, the adrenal gland, the colon, the bladder, and the pads of the paws. Overall, Esr2-iCre mice will serve as a novel line for conditionally ablating genes in Esr2-expressing tissues, identifying novel Esr2-expressing cells, and differentiating the functions of ESR2 and ESR1.

  20. The role of peroxisomal fatty acyl-CoA beta-oxidation in bile acid biosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, H.; Miwa, A. (Josai Univ., Saitama (Japan))

    1989-11-01

    The physiological role of the peroxisomal fatty acyl-CoA beta-oxidizing system (FAOS) is not yet established. We speculated that there might be a relationship between peroxisomal degradation of long-chain fatty acids in the liver and the biosynthesis of bile acids. This was investigated using (1-{sup 14}C)butyric acid and (1-{sup 14}C)lignoceric acid as substrates of FAOS in mitochondria and peroxisomes, respectively. The incorporation of ({sup 14}C)lignoceric acid into primary bile acids was approximately four times higher than that of ({sup 14}C)butyric acid (in terms of C-2 units). The pools of these two fatty acids in the liver were exceedingly small. The incorporations of radioactivity into the primary bile acids were strongly inhibited by administration of aminotriazole, which is a specific inhibitor of peroxisomal FAOS in vivo. Aminotriazole inhibited preferentially the formation of cholate, the major primary bile acid, from both ({sup 14}C)lignoceric acid and ({sup 14}C)butyric acid, rather than the formation of chenodeoxycholate. The former inhibition was about 70% and the latter was approximately 40-50%. In view of reports that cholate is biosynthesized from endogenous cholesterol, the above results indicate that peroxisomal FAOS may have an anabolic function, supplying acetyl CoA for bile acid biosynthesis.

  1. Bile acid nuclear receptor FXR and digestive system diseases

    Directory of Open Access Journals (Sweden)

    Lili Ding

    2015-03-01

    Full Text Available Bile acids (BAs are not only digestive surfactants but also important cell signaling molecules, which stimulate several signaling pathways to regulate some important biological processes. The bile-acid-activated nuclear receptor, farnesoid X receptor (FXR, plays a pivotal role in regulating bile acid, lipid and glucose homeostasis as well as in regulating the inflammatory responses, barrier function and prevention of bacterial translocation in the intestinal tract. As expected, FXR is involved in the pathophysiology of a wide range of diseases of gastrointestinal tract, including inflammatory bowel disease, colorectal cancer and type 2 diabetes. In this review, we discuss current knowledge of the roles of FXR in physiology of the digestive system and the related diseases. Better understanding of the roles of FXR in digestive system will accelerate the development of FXR ligands/modulators for the treatment of digestive system diseases.

  2. NMDA-receptor activation but not ion flux is required for amyloid-beta induced synaptic depression.

    Directory of Open Access Journals (Sweden)

    Albert Tamburri

    Full Text Available Alzheimer disease is characterized by a gradual decrease of synaptic function and, ultimately, by neuronal loss. There is considerable evidence supporting the involvement of oligomeric amyloid-beta (Aβ in the etiology of Alzheimer's disease. Historically, AD research has mainly focused on the long-term changes caused by Aβ rather than analyzing its immediate effects. Here we show that acute perfusion of hippocampal slice cultures with oligomeric Aβ depresses synaptic transmission within 20 minutes. This depression is dependent on synaptic stimulation and the activation of NMDA-receptors, but not on NMDA-receptor mediated ion flux. It, therefore, appears that Aβ dependent synaptic depression is mediated through a use-dependent metabotropic-like mechanism of the NMDA-receptor, but does not involve NMDA-receptor mediated synaptic transmission, i.e. it is independent of calcium flux through the NMDA-receptor.

  3. Retinoic acid receptor alpha is associated with tamoxifen resistance in breast cancer

    OpenAIRE

    Johansson, Henrik J; Sanchez, Betzabe C.; Mundt, Filip; Forshed, Jenny; Kovacs, Aniko; Panizza, Elena; Hultin-Rosenberg, Lina; Lundgren, Bo; Martens, Ulf; Máthé, Gyöngyvér; Yakhini, Zohar; Helou, Khalil; Krawiec, Kamilla; Kanter, Lena; Hjerpe, Anders

    2013-01-01

    About one-third of oestrogen receptor alpha-positive breast cancer patients treated with tamoxifen relapse. Here we identify the nuclear receptor retinoic acid receptor alpha as a marker of tamoxifen resistance. Using quantitative mass spectrometry-based proteomics, we show that retinoic acid receptor alpha protein networks and levels differ in a tamoxifen-sensitive (MCF7) and a tamoxifen-resistant (LCC2) cell line. High intratumoural retinoic acid receptor alpha protein levels also correlate...

  4. Selective agonists of retinoic acid receptors: comparative toxicokinetics and embryonic exposure.

    Science.gov (United States)

    Arafa, H M; Elmazar, M M; Hamada, F M; Reichert, U; Shroot, B; Nau, H

    2000-01-01

    Three biologically active synthetic retinoids were investigated that bind selectively to retinoic acid receptors RARs (alpha, beta and gamma). The retinoids were previously demonstrated to have different teratogenic effects in the mouse in terms of potency and regioselectivity. The teratogenic potency rank order (alpha >beta >gamma) was found to be more or less compatible with the receptor binding affinities and transactivation potencies of the retinoid ligands to their respective receptors. The RARalpha agonist (Am580; CD336) induced a wide spectrum of malformations; CD2019 (RARbeta agonist) and especially CD437 (RARgamma agonist) produced more restricted defects. In the current study we tried to address whether the differences in teratogenic effects are solely related to binding affinity and transactivation differences or also due to differences in embryonic exposure. Therefore, transplacental kinetics of the ligands were assessed following administration of a single oral dose of 15 mg/kg of either retinoid given to NMRI mice on day 11 of gestation. Am580 was rapidly transferred to the embryo resulting in the highest embryonic exposure [embryo to maternal plasma area under the time vs concentration curve (AUC)(0-24 h )ratio (E/M) was 1.7], in accordance with its highest teratogenic potency. The low placental transfer of CD2019 (E/M of 0.3) was compatible with its lower teratogenic potential. Of major interest was the finding that the CD437, though being least teratogenic, exhibited considerable embryonic exposure (E/M of 0.6). These findings suggest that both the embryonic exposure and receptor binding transactivation selectivity are crucial determinants of the teratogenicity of these retinoid ligands.

  5. Molecular pharmacology of homologues of ibotenic acid at cloned metabotropic glutamic acid receptors

    DEFF Research Database (Denmark)

    Bräuner-Osborne, Hans; Nielsen, B; Krogsgaard-Larsen, P

    1998-01-01

    We have studied the effects of the enantiomers of 2-amino-3-(3-hydroxyisoxazol-5-yl)propionic acid (homoibotenic acid, HIBO) and analogues substituted with a methyl, bromo or butyl group in the four position of the ring at cloned metabotropic glutamate (mGlu) receptors expressed in Chinese hamste...

  6. Role of Bile Acids and Bile Acid Receptors in Metabolic Regulation

    NARCIS (Netherlands)

    Lefebvre, Philippe; Cariou, Bertrand; Lien, Fleur; Kuipers, Folkert; Staels, Bart

    2009-01-01

    Lefebvre P, Cariou B, Lien F, Kuipers F, Staels B. Role of Bile Acids and Bile Acid Receptors in Metabolic Regulation. Physiol Rev 89: 147-191,2009; doi: 10.1152/physrev.00010.2008. - The incidence of the metabolic syndrome has taken epidemic proportions in the past decades, contributing to an incre

  7. Differential interleukin-1 receptor antagonism on pancreatic beta and alpha cells. Studies in rodent and human islets and in normal rats

    DEFF Research Database (Denmark)

    Zumsteg, U; Reimers, J I; Pociot, F;

    1993-01-01

    , mouse and human islets exposed to recombinant human interleukin-1 beta, and on interleukin-1 beta induced changes in blood glucose, serum insulin and serum glucagon levels in Wistar Kyoto rats. The interleukin-1 receptor antagonist reduced the co-mitogenic effect of interleukin-1 beta on mouse and rat......The monokines interleukin-1 alpha and -beta have been implicated as effector molecules in the immune-mediated pancreatic beta-cell destruction leading to insulin-dependent diabetes mellitus. Here we investigated the effects of interleukin-1 receptor antagonism on insulin and glucagon release of rat...... thymocytes with a 50% inhibitory concentration of 10- and 100-fold molar excess, respectively. Complete inhibition was obtained with a 100-1,000-fold molar excess. However, at a 100-fold molar excess the interleukin-1 receptor antagonist did not antagonise the potentiating effect of interleukin-1 beta on rat...

  8. Mutant U5A cells are complemented by an interferon-alpha beta receptor subunit generated by alternative processing of a new member of a cytokine receptor gene cluster.

    Science.gov (United States)

    Lutfalla, G; Holland, S J; Cinato, E; Monneron, D; Reboul, J; Rogers, N C; Smith, J M; Stark, G R; Gardiner, K; Mogensen, K E

    1995-10-16

    The cellular receptor for the alpha/beta interferons contains at least two components that interact with interferon. The ifnar1 component is well characterized and a putative ifnar2 cDNA has recently been identified. We have cloned the gene for ifnar2 and show that it produces four different transcripts encoding three different polypeptides that are generated by exon skipping, alternative splicing and differential use of polyadenylation sites. One polypeptide is likely to be secreted and two are transmembrane proteins with identical extracellular and transmembrane domains but divergent cytoplasmic tails of 67 and 251 amino acids. A mutant cell line U5A, completely defective in IFN-alpha beta binding and response, has been isolated and characterized. Expression in U5A cells of the polypeptide with the long cytoplasmic domain reconstitutes a functional receptor that restores normal interferon binding, activation of the JAK/STAT signal transduction pathway, interferon-inducible gene expression and antiviral response. The IFNAR2 gene maps at 0.5 kb from the CRFB4 gene, establishing that together IFNAR2, CRFB4, IFNAR1 and AF1 form a cluster of class II cytokine receptor genes on human chromosome 21.

  9. Molecular analysis of T-cell receptor beta genes in cutaneous T-cell lymphoma reveals Jbeta1 bias.

    Science.gov (United States)

    Morgan, Suzanne M; Hodges, Elizabeth; Mitchell, Tracey J; Harris, Susan; Whittaker, Sean J; Smith, John L

    2006-08-01

    Molecular characterization of T-cell receptor junctional region sequences in cutaneous T-cell lymphoma had not been previously reported. We have examined in detail the features of the T-cell receptor beta (TCRB) gene rearrangements in 20 individuals with well-defined stages of cutaneous T-cell lymphoma (CTCL) comprising 10 cases with early-stage mycosis fungoides (MF) and 10 cases with late-stage MF or Sezary syndrome. Using BIOMED-2 PCR primers, we detected a high frequency of clonally rearranged TCR gamma and TCRB genes (17/20 and 15/20 cases, respectively). We carried out sequencing analysis of each complete clonal variable (V)beta-diversity (D)beta-joining(J)beta fingerprint generated by PCR amplification, and determined the primary structure of the Vbeta-Dbeta-Jbeta junctional regions. We observed considerable diversity in the T-cell receptor Vbeta gene usage and complementarity-determining region 3 loops. Although we found that TCRB gene usage in CTCL and normal individuals share common features, our analysis also revealed preferential usage of Jbeta1 genes in all cases with advanced stages of disease.

  10. Live Borrelia burgdorferi preferentially activate interleukin-1 beta gene expression and protein synthesis over the interleukin-1 receptor antagonist.

    Science.gov (United States)

    Miller, L C; Isa, S; Vannier, E; Georgilis, K; Steere, A C; Dinarello, C A

    1992-01-01

    Lyme arthritis is one of the few forms of chronic arthritis in which the cause is known with certainty. Because cytokines are thought to contribute to the pathogenesis of chronic arthritis, we investigated the effect of the Lyme disease spirochete, Borrelia burgdorferi, on the gene expression and synthesis of IL-1 beta and the IL-1 receptor antagonist (IL-1ra) in human peripheral blood mononuclear cells. Live B. burgdorferi induced fivefold more IL-1 beta than IL-1 alpha and sevenfold more IL-1 beta than IL-1ra; LPS or sonicated B. burgdorferi induced similar amounts of all three cytokines. This preferential induction of IL-1 beta was most dramatic in response to a low passage, virulent preparation of B. burgdorferi vs. three high passage avirulent strains. No difference in induction of IL-1ra was seen between these strains. The marked induction of IL-1 beta was partially diminished by heat-treatment and abrogated by sonication; IL-1ra was not affected. This suggested that a membrane component(s) accounted for the preferential induction of IL-1 beta. However, recombinant outer surface protein beta induced little IL-1 beta. By 4 h after stimulation, B. burgdorferi induced sixfold more IL-1 beta protein than LPS. In contrast to LPS-induced IL-1 beta mRNA which reached maximal accumulation after 3 h, B. burgdorferi-induced IL-1 beta mRNA showed biphasic elevations at 3 and 18 h. B. burgdorferi-induced IL-1ra mRNA peaked at 12 h, whereas LPS-induced IL-1ra mRNA peaked at 9 h. IL-1 beta synthesis increased in response to increasing numbers of spirochetes, whereas IL-1ra synthesis did not. The preferential induction by B. burgdorferi of IL-1 beta over IL-1ra is an example of excess agonist over antagonist synthesis induced by a microbial pathogen, and may contribute to the destructive lesion of Lyme arthritis. Images PMID:1387885

  11. 4-Phenylbutyric Acid Attenuates Pancreatic Beta-Cell Injury in Rats with Experimental Severe Acute Pancreatitis.

    Science.gov (United States)

    Hong, Yu-Pu; Guo, Wen-Yi; Wang, Wei-Xing; Zhao, Liang; Xiang, Ming-Wei; Mei, Fang-Chao; Abliz, Ablikim; Hu, Peng; Deng, Wen-Hong; Yu, Jia

    2016-01-01

    Endoplasmic reticulum (ER) stress is a particular process with an imbalance of homeostasis, which plays an important role in pancreatitis, but little is known about how ER stress is implicated in severe acute pancreatitis (SAP) induced pancreatic beta-cell injury. To investigate the effect of 4-phenylbutyric acid (4-PBA) on the beta-cell injury following SAP and the underlying mechanism, twenty-four Sprague-Dawley rats were randomly divided into sham-operation (SO) group, SAP model group, and 4-PBA treatment group. SAP model was induced by infusion of 5% sodium taurocholate into the biliopancreatic duct. 4-PBA or normal saline was injected intraperitoneally for 3 days in respective group before successful modeling. Results showed that 4-PBA attenuated the following: (1) pancreas and islet pathological injuries, (2) serum TNF-α and IL-1β, (3) serum insulin and glucose, (4) beta-cell ultrastructural changes, (5) ER stress markers (BiP, ORP150, and CHOP), Caspase-3, and insulin expression in islet. These results suggested that 4-PBA mitigates pancreatic beta-cell injury and endocrine disorder in SAP, presumably because of its role in inhibiting excessive endoplasmic reticulum stress. This may serve as a new therapeutic target for reducing pancreatic beta-cell injury and endocrine disorder in SAP upon 4-PBA treatment. PMID:27656209

  12. Interleukin 2 receptor beta chain expressed in an oligodendroglioma line binds interleukin 2 and delivers growth signal.

    OpenAIRE

    Okamoto, Y; Minamoto, S; Shimizu, K.; Mogami, H; Taniguchi, T.

    1990-01-01

    Interleukin 2 (IL-2) is a potent growth factor for T lymphocytes, playing a crucial role in the immune response. In view of the considerable evidence that the immunoregulatory cytokines (or lymphokines) also play a role in the growth and differentiation of cells in the central nervous system (CNS), we examined the operation of the IL-2 system in a cell line of CNS origin by expressing a cDNA encoding the beta chain of the human IL-2 receptor (IL-2R beta, a 75-kDa protein). When the cDNA was e...

  13. Receptor tyrosine phosphatase beta is expressed in the form of proteoglycan and binds to the extracellular matrix protein tenascin

    DEFF Research Database (Denmark)

    Barnea, G; Grumet, M; Milev, P;

    1994-01-01

    immunohistochemical studies indicated that both RPTP beta and the extracellular matrix protein tenascin are localized in similar regions of the central nervous system. We have performed co-aggregation assays with red and green Co-vaspheres coated with tenascin and 3F8 PG, respectively, showing that the extracellular...... domain of RPTP beta (3F8 PG) binds specifically to tenascin. The interaction between a receptor tyrosine phosphatase and an extracellular matrix protein may have a role in development of the mammalian central nervous system....

  14. Seizure control by decanoic acid through direct AMPA receptor inhibition.

    Science.gov (United States)

    Chang, Pishan; Augustin, Katrin; Boddum, Kim; Williams, Sophie; Sun, Min; Terschak, John A; Hardege, Jörg D; Chen, Philip E; Walker, Matthew C; Williams, Robin S B

    2016-02-01

    The medium chain triglyceride ketogenic diet is an established treatment for drug-resistant epilepsy that increases plasma levels of decanoic acid and ketones. Recently, decanoic acid has been shown to provide seizure control in vivo, yet its mechanism of action remains unclear. Here we show that decanoic acid, but not the ketones β-hydroxybutryate or acetone, shows antiseizure activity in two acute ex vivo rat hippocampal slice models of epileptiform activity. To search for a mechanism of decanoic acid, we show it has a strong inhibitory effect on excitatory, but not inhibitory, neurotransmission in hippocampal slices. Using heterologous expression of excitatory ionotropic glutamate receptor AMPA subunits in Xenopus oocytes, we show that this effect is through direct AMPA receptor inhibition, a target shared by a recently introduced epilepsy treatment perampanel. Decanoic acid acts as a non-competitive antagonist at therapeutically relevant concentrations, in a voltage- and subunit-dependent manner, and this is sufficient to explain its antiseizure effects. This inhibitory effect is likely to be caused by binding to sites on the M3 helix of the AMPA-GluA2 transmembrane domain; independent from the binding site of perampanel. Together our results indicate that the direct inhibition of excitatory neurotransmission by decanoic acid in the brain contributes to the anti-convulsant effect of the medium chain triglyceride ketogenic diet. PMID:26608744

  15. Complex pharmacology of novel allosteric free fatty acid 3 receptor ligands

    DEFF Research Database (Denmark)

    Hudson, Brian D; Christiansen, Elisabeth; Murdoch, Hannah;

    2014-01-01

    Analysis of the roles of the short chain fatty acid receptor, free fatty acid 3 receptor (FFA3), has been severely limited by the low potency of its endogenous ligands, the crossover of function of these on the closely related free fatty acid 2 receptor, and a dearth of FFA3-selective synthetic l...

  16. Islet-selectivity of G-protein coupled receptor ligands evaluated for PET imaging of pancreatic {beta}-cell mass

    Energy Technology Data Exchange (ETDEWEB)

    Cline, Gary W., E-mail: gary.cline@yale.edu [Yale University School of Medicine (United States); Zhao, Xiaojian [Yale University School of Medicine (United States); Jakowski, Amy B.; Soeller, Walter C.; Treadway, Judith L. [Pfizer Global Research and Development, Pfizer Inc., Groton CT (United States)

    2011-09-02

    Highlights: {yields} We screened G-protein coupled receptors for imaging pancreatic. {yields} Database mining and immunohistochemistry identified GPCRs enriched in {beta}-cells. {yields} In vitro and in vivo assays were used to determine exocrine vs endocrine specificity. {yields} GPCR candidates for imaging of {beta}-cell mass are Prokineticin-1R, mGluR5, and GLP-1R. -- Abstract: A critical unmet need exists for methods to quantitatively measure endogenous pancreatic {beta}-cell mass (BCM) for the clinical evaluation of therapies to prevent or reverse loss of BCM and diabetes progression. Our objective was to identify G-protein coupled receptors (GPCRs) that are expressed with a high degree of specificity to islet {beta}-cells for receptor-targeted imaging of BCM. GPCRs enriched in pancreatic islets relative to pancreas acinar and hepatic tissue were identified using a database screen. Islet-specific expression was confirmed by human pancreas immunohistochemistry (IHC). In vitro selectivity assessment was determined from the binding and uptake of radiolabeled ligands to the rat insulinoma INS-1 832/13 cell line and isolated rat islets relative to the exocrine pancreas cell-type, PANC-1. Tail-vein injections of radioligands into rats were used to determine favorable image criteria of in vivo biodistribution to the pancreas relative to other internal organs (i.e., liver, spleen, stomach, and lungs). Database and IHC screening identified four candidate receptors for further in vitro and in vivo evaluation for PET imaging of BCM: prokineticin-1 receptor (PK-1R), metabotropic glutamate receptor type-5 (mGluR5), neuropeptide Y-2 receptor (NPY-2R), and glucagon-like peptide 1 receptor (GLP-1R). In vitro specificity ratios gave the following receptor rank order: PK-1R > GLP-1R > NPY-2R > mGluR5. The biodistribution rank order of selectivity to the pancreas was found to be PK-1R > VMAT2 {approx} GLP-1R > mGluR5. Favorable islet selectivity and biodistribution

  17. Influence of the aluminium impregnation [ Al(NO33] in the beta zeolite over its acidity

    Directory of Open Access Journals (Sweden)

    Francisco José Sánchez Castellanos

    2010-04-01

    Full Text Available Beta zeolite was impregnated with [ Al(NO33], increasing the aluminium content in increments of 0.05% from 0.00% to 0.25%. A parallel treatment with 0.05% sulphuric acid was also performed; in both cases, methanol was used as solvent (disperse phase. Cation exchange capacity (CEC, ammonia chemisorption, infrared spectroscopy (FIT-IR, scanning electronic microscopy (SEM, X-Ray powder diffraction (XRD, atomic absorption spectroscopy (AAS, titration with sodium hydroxide and nitrogen physisorption at 77K were used to carry out the physical and chemical characterization of the catalysts. Futhermore, the catalysts were employed in the esterification of ethanol with acetic acid, to quantify the effect of aluminium impregnation over the beta zeolite.

  18. Evaluation of estrogen receptor alpha and beta and progesterone receptor expression and correlation with clinicopathologic factors and proliferative marker Ki-67 in breast cancers

    DEFF Research Database (Denmark)

    Rosa, Fabíola E; Caldeira, José R F; Felipes, Joice;

    2008-01-01

    To elucidate the molecular profile of hormonal steroid receptor status, we analyzed ER-alpha, ER-beta, and PGR mRNA and protein expression in 80 breast carcinomas using reverse transcriptase polymerase chain reaction (RT-PCR), quantitative RT-PCR, and immunohistochemical analysis. Qualitative...... analysis revealed positive expression of ER-alpha, ER-beta, and PGR mRNA in 48%, 59%, and 48% of the breast carcinomas, respectively. ER-alpha, ER-beta, and PGR transcript overexpression was observed in 51%, 0%, and 12% of the cases, respectively, whereas moderate or strong protein expression was detected...... in 68%, 78%, and 49% of the cases, respectively. Tumor grade was negatively correlated with transcript and protein levels of ER-alpha (P = .0169 and P = .0006, respectively) and PGR (P = .0034 and P = .0005, respectively). Similarly, proliferative index Ki-67 was negatively associated with transcript...

  19. The antinociceptive effects of ferulic acid on neuropathic pain: involvement of descending monoaminergic system and opioid receptors.

    Science.gov (United States)

    Xu, Ying; Lin, Dan; Yu, Xuefeng; Xie, Xupei; Wang, Liqun; Lian, Lejing; Fei, Ning; Chen, Jie; Zhu, Naping; Wang, Gang; Huang, Xianfeng; Pan, Jianchun

    2016-04-12

    Neuropathic pain can be considered as a form of chronic stress that may share common neuropathological mechanism between pain and stress-related depression and respond to similar treatment. Ferulic acid (FA) is a major active component of angelica sinensis and has been reported to exert antidepressant-like effects; however, it remains unknown whether FA ameliorate chronic constriction injury (CCI)-induced neuropathic pain and the involvement of descending monoaminergic system and opioid receptors. Chronic treatment with FA (20, 40 and 80 mg/kg) ameliorated mechanical allodynia and thermal hyperalgesia in von Frey hair and hot plate tasks, accompanied by increasing spinal noradrenaline (NA) and serotonin (5-HT) levels. Subsequent study suggested that treatment of CCI animals with 40 and 80 mg/kg FA also inhibited spinal MAO-A levels. FA's effects on mechanical allodynia or thermal hyperalgesiawas blocked by 6-hydroxydopamine (6-OHDA) or p-chlorophenylalanine (PCPA) via pharmacological depletion of spinal noradrenaline or serotonin. Moreover, the anti-allodynic action of FA on mechanical stimuli was prevented by pre-treatment with beta2-adrenoceptor antagonist ICI 118,551, or by the delta-opioid receptor antagonist naltrindole. While the anti-hyperalgesia on thermal stimuli induced by FA was blocked by pre-treatment with 5-HT1A receptor antagonist WAY-100635, or with the irreversible mu-opioid receptor antagonist beta-funaltrexamine. These results suggest that the effect of FA on neuropathic pain is potentially mediated via amelioration of the descending monoaminergic system that coupled with spinal beta2- and 5-HT1A receptors and the downstream delta- and mu-opioid receptors differentially. PMID:26967251

  20. Beta-Adrenergic Receptor Population is Up-Regulated in Chicken Skeletal Muscle Cells Treated with Forskolin

    Science.gov (United States)

    Bridge, K. Y.; Young, R. B.; Vaughn, J. R.

    1998-01-01

    Skeletal muscle hypertrophy is promoted by in vivo administration of beta-adrenergic receptor (betaAR) agonists. These compounds presumably exert their physiological action through the betaAR, and alterations in the population of betaAR could potentially change the ability of the cell to respond to the betaAR agonists. Since the intracellular chemical signal generated by the betaAR is cyclic AMP (cAMP), experiments were initiated in primary chicken muscle cell cultures to determine if artificial elevation of intracellular cAMP by treatment with forskolin would alter the population of functional betaAR expressed on the surface of muscle cells. Chicken skeletal muscle cells after 7 days in culture were employed for the experiments because muscle cells have attained a steady state with respect to muscle protein metabolism at this stage. Cells were treated with 0-10 microM forskolin for a total of three days. At the end of the 1, 2, and 3 day treatment intervals, the concentration of cAMP and the betaAR population were measured. Receptor population was measured in intact muscle cell cultures as the difference between total binding of [H-3]CGP-12177 and non-specific binding of [H-3]CGP-12177 in the presence of 1 microM propranolol. Intracellular cAMP concentration was measured by radioimmunoassay. The concentration of cAMP in forskolin-treated cells increased up to 10-fold in a dose dependent manner. Increasing concentrations of forskolin also led to an increase in betaAR population, with a maximum increase of approximately 50% at 10 microM. This increase in PAR population was apparent after only 1 day of treatment, and the pattern of increase was maintained for all 3 days of the treatment period. Thus, increasing the intracellular concentration of cAMP leads to up-regulation of betaAR population. The effect of forskolin on the quantity and apparent synthesis rate of the heavy chain of myosin (mhc) were also investigated. A maximum increase of 50% in the quantity of mhc

  1. Tumour nuclear oestrogen receptor beta 1 correlates inversely with parathyroid tumour weight.

    Science.gov (United States)

    Haglund, Felix; Rosin, Gustaf; Nilsson, Inga-Lena; Juhlin, C Christofer; Pernow, Ylva; Norenstedt, Sophie; Dinets, Andrii; Larsson, Catharina; Hartman, Johan; Höög, Anders

    2015-03-01

    Primary hyperparathyroidism (PHPT) is a common endocrinopathy, frequently caused by a parathyroid adenoma, rarely by a parathyroid carcinoma that lacks effective oncological treatment. As the majority of cases are present in postmenopausal women, oestrogen signalling has been implicated in the tumourigenesis. Oestrogen receptor beta 1 (ERB1) and ERB2 have been recently identified in parathyroid adenomas, the former inducing genes coupled to tumour apoptosis. We applied immunohistochemistry and slide digitalisation to quantify nuclear ERB1 and ERB2 in 172 parathyroid adenomas, atypical adenomas and carcinomas, and ten normal parathyroid glands. All the normal parathyroid glands expressed ERB1 and ERB2. The majority of tumours expressed ERB1 (70.6%) at varying intensities, and ERB2 (96.5%) at strong intensities. Parathyroid carcinomas expressed ERB1 in three out of six cases and ERB2 in five out of six cases. The intensity of tumour nuclear ERB1 staining significantly correlated inversely with tumour weight (P=0.011), and patients whose tumours were classified as ERB1-negative had significantly greater tumour weight as well as higher serum calcium (P=0.002) and parathyroid hormone levels (P=0.003). Additionally, tumour nuclear ERB1 was not expressed differentially with respect to sex or age of the patient. Levels of tumour nuclear ERB2 did not correlate with clinical characteristics. In conclusion, decreased ERB1 immunoreactivity is associated with increased tumour weight in parathyroid adenomas. Given the previously reported correlation with tumour-suppressive signalling, selective oestrogen receptor modulation (SERMs) may play a role in the treatment of parathyroid carcinomas. Future studies of SERMs and oestrogen treatment in PHPT should consider tumour weight as a potential factor in pharmacological responsiveness. PMID:25648860

  2. Synthesis and activity of 2-oxoamides containing long chain beta-amino acids.

    Science.gov (United States)

    Constantinou-Kokotou, Violetta; Peristeraki, Anna; Kokotos, Christoforos G; Six, David A; Dennis, Edward A

    2005-07-01

    2-Oxoamides based on long chain beta-amino acids were synthesized. 1-Benzyl substituted long chain amines, needed for such synthesis, were synthesized starting from Boc-phenylalaninol. The oxidative conversion of a phenyl group to a carboxyl group was used as the key transformation synthetic step. The compounds synthesized were studied for their activity against GIVA PLA(2), and were proven to be weak inhibitors. PMID:15635664

  3. Effects of. beta. -cyclodextrin on the luminescence of para amino acids

    Energy Technology Data Exchange (ETDEWEB)

    Turnbull, J.H.; Walker, R.G. (Royal Military Coll. of Science, Shrivenham (UK))

    1981-05-11

    Beta-cyclodextrin has been added to para amino benzoic acid (PABA) and luminescence changes observed for the PABA anion. The intensity of fluorescence was increased upon complexation of the PABA at 298 K due to the prevention of collisional deactivation of the PABA, but at 77 K the fluorescence was reduced due to the increase of vibrational deactivation modes available to the complex relative to the free PABA. The luminescence effects were interpreted as inclusion complexation of the PABA anion.

  4. A role for Peroxisome Proliferator-Activated Receptor Beta in T cell development

    Science.gov (United States)

    Mothe-Satney, Isabelle; Murdaca, Joseph; Sibille, Brigitte; Rousseau, Anne-Sophie; Squillace, Raphaëlle; Le Menn, Gwenaëlle; Rekima, Akila; Larbret, Frederic; Pelé, Juline; Verhasselt, Valérie; Grimaldi, Paul A.; Neels, Jaap G.

    2016-01-01

    Metabolism plays an important role in T cell biology and changes in metabolism drive T cell differentiation and fate. Most research on the role of metabolism in T lymphocytes focuses on mature T cells while only few studies have investigated the role of metabolism in T cell development. In this study, we report that activation or overexpression of the transcription factor Peroxisome Proliferator-Activated Receptor β (PPARβ) increases fatty acid oxidation in T cells. Furthermore, using both in vivo and in vitro models, we demonstrate that PPARβ activation/overexpression inhibits thymic T cell development by decreasing proliferation of CD4−CD8− double-negative stage 4 (DN4) thymocytes. These results support a model where PPARβ activation/overexpression favours fatty acid- instead of glucose-oxidation in developing T cells, thereby hampering the proliferative burst normally occurring at the DN4 stage of T cell development. As a consequence, the αβ T cells that are derived from DN4 thymocytes are dramatically decreased in peripheral lymphoid tissues, while the γδ T cell population remains untouched. This is the first report of a direct role for a member of the PPAR family of nuclear receptors in the development of T cells. PMID:27680392

  5. Identification of COUP-TFII Orphan Nuclear Receptor as a Retinoic Acid-Activated Receptor

    Energy Technology Data Exchange (ETDEWEB)

    Kruse, Schoen W; Suino-Powell, Kelly; Zhou, X Edward; Kretschman, Jennifer E; Reynolds, Ross; Vonrhein, Clemens; Xu, Yong; Wang, Liliang; Tsai, Sophia Y; Tsai, Ming-Jer; Xu, H Eric [Baylor; (Van Andel); (Globel Phasing); (Grand Valley)

    2010-01-12

    The chicken ovalbumin upstream promoter-transcription factors (COUP-TFI and II) make up the most conserved subfamily of nuclear receptors that play key roles in angiogenesis, neuronal development, organogenesis, cell fate determination, and metabolic homeostasis. Although the biological functions of COUP-TFs have been studied extensively, little is known of their structural features or aspects of ligand regulation. Here we report the ligand-free 1.48 {angstrom} crystal structure of the human COUP-TFII ligand-binding domain. The structure reveals an autorepressed conformation of the receptor, where helix {alpha}10 is bent into the ligand-binding pocket and the activation function-2 helix is folded into the cofactor binding site, thus preventing the recruitment of coactivators. In contrast, in multiple cell lines, COUP-TFII exhibits constitutive transcriptional activity, which can be further potentiated by nuclear receptor coactivators. Mutations designed to disrupt cofactor binding, dimerization, and ligand binding, substantially reduce the COUP-TFII transcriptional activity. Importantly, retinoid acids are able to promote COUP-TFII to recruit coactivators and activate a COUP-TF reporter construct. Although the concentration needed is higher than the physiological levels of retinoic acids, these findings demonstrate that COUP-TFII is a ligand-regulated nuclear receptor, in which ligands activate the receptor by releasing it from the autorepressed conformation.

  6. Bace1 activity impairs neuronal glucose metabolism: rescue by beta-hydroxybutyrate and lipoic acid

    Directory of Open Access Journals (Sweden)

    John A Findlay

    2015-10-01

    Full Text Available Glucose hypometabolism and impaired mitochondrial function in neurons have been suggested to play early and perhaps causative roles in Alzheimer’s disease (AD pathogenesis. Activity of the aspartic acid protease, beta-site amyloid precursor protein (APP cleaving enzyme 1 (BACE1, responsible for beta amyloid peptide generation, has recently been demonstrated to modify glucose metabolism. We therefore examined, using a human neuroblastoma (SH-SY5Y cell line, whether increased BACE1 activity is responsible for a reduction in cellular glucose metabolism. Overexpression of active BACE1, but not a protease-dead mutant BACE1, protein in SH-SY5Y cells reduced glucose oxidation and the basal oxygen consumption rate, which was associated with a compensatory increase in glycolysis. Increased BACE1 activity had no effect on the mitochondrial electron transfer process but was found to diminish substrate delivery to the mitochondria by inhibition of key mitochondrial decarboxylation reaction enzymes. This BACE1 activity-dependent deficit in glucose oxidation was alleviated by the presence of beta hydroxybutyrate or α-lipoic acid. Consequently our data indicate that raised cellular BACE1 activity drives reduced glucose oxidation in a human neuronal cell line through impairments in the activity of specific tricarboxylic acid cycle enzymes. Because this bioenergetic deficit is recoverable by neutraceutical compounds we suggest that such agents, perhaps in conjunction with BACE1 inhibitors, may be an effective therapeutic strategy in the early-stage management or treatment of AD.

  7. Beta-receptor activation increases sodium current in guinea pig heart

    Institute of Scientific and Technical Information of China (English)

    Hong-wei WANG; Zhi-fang YANG; Yin ZHANG; Jian-min YANG; Yuan-mou LIU; Ci-zhen LI

    2009-01-01

    Aim: To study the influence of β-receptor activation on sodium channel current and the physiological significance of increased sodium current with regard to the increased cardiac output caused by sympathetic excitation.Methods: Multiple experimental approaches, including ECG, action potential recording with conventional microelectrodes, whole-cell current measurements, single-channel recordings, and pumping-force measurements, were applied to guinea pig hearts and isolated ventricular myocytes.Results: Isoprenaline was found to dose-dependently shorten QRS waves, increase the amplitude and the Vmaxof action potentials, aug-ment the fast sodium current, and increase the occurrence frequencies and open time constants of the long-open and burst modes of the sodium channel. Increased levels of membrane-permeable cAMP have similar effects. In the presence of a calcium channel blocker, TTX reversed the increased pumping force produced by isoprenaline.Conclusion: Beta-adrenergic modulation increases the inward sodium current and accelerates the conduction velocity within the ventri-cles by changing the sodium channel modes, which might both be conducive to the synchronous contraction of the heart and enhance its pumping function.

  8. Identification of higenamine in Radix Aconiti Lateralis Preparata as a beta2-adrenergic receptor agonist

    Institute of Scientific and Technical Information of China (English)

    Gang BAI; Yang YANG; Qian SHI; Ze LIU; Qi ZHANG; Yuan-yuan ZHU

    2008-01-01

    Aim:To screen beta2-adrenergic receptor (β+-AR) agonists from Radix Aconiti Lateralis Preparata (RALP) as potential drug leads for asthma using a sensi-tive cell-based agonist assay.Methods:The β+-AR gene was stably expressed by Chinese hamster ovary (CHO) cells also stably expressing a cyclic adenosine monophosphate (AMP) response element-linked enhanced green fluorescent pro-tein reporter gene.The cells were used to screen agonists from high-performance liquid chromatographic fractions of an extract of RALE The fraction with the highest activity was selected for further compound isolation and the study of the structure-activity relationship.Its active compound was further identified by chromatography and mass spectrometry.Results:Bioactivity-directed fraction-ation of the crude extract of RALP led to the isolation and characterization of the effective compound,namely hignamine.It could dose-dependently relax the iso-lated guinea pig trachea strip precontraction with acetylcholine with EC50 value of (2.60±0.36)x 10-5 mol/L.Further in vivo studies also displayed that higuamine could protect experimental asthma model induced by histamine in guinea pigs to prolong the latent periods of asthma.Conclusion:Hignamine,as a β2-AR ago-nist existing in the extract of RALE is the key compound contributing to the suc-cessful relief of the bronchoconstriction.

  9. [Cloning of gene fragment of estrogen receptor-beta and its expression in mouse embryo].

    Science.gov (United States)

    Zhang, Zi-Feng; Fan, Shao-Hua; Lu, Jun; Wu, Dong-Mei; Shan, Qun; Hu, Bin; Li, Fei; Zheng, Yuan-Lin

    2008-03-01

    In order to study the expression and regulation effects of estrogen receptor-beta (ERbeta) in the development of mouse embryo, the primer of ERbeta was designed, the ERbeta fragment was first obtained by RT-PCR and subcloned into plasmids pGEM- 3Z, then the recombinant plasmids were linearized with the restriction enzymes of EcoRand Hind. Using Sp6 and T7 RNA polymerase, the digoxigenin(dig) labeled sense and anti-sense probes were transcriped in vitro, respectively. Then the expression of ERbeta in mouse embryo was examined with the probes by whole-mount in situ hybridization. The results indicated that ERbeta is expressed in the brain, spinal neural tube, genital ridge, pericardium, limb bud and mandibular arch of 10.5 dpc embryo, and is also expressed in the telencephalon, mesencephalon, medulla oblongata, spinal cord and limb bud of 13.5 dpc embryo. These results suggest that ERbeta maybe play a role of regulation in sexual differentiation, primal differentiation of neural tube, further differentiation of three primary cerebral vesicles and spinal cord, generation and differentiation of bone and cartilage of limb bud, development of pericardium and configuration differentiation of mandibular in mouse embryo. PMID:18332005

  10. Blockade of lysophosphatidic acid receptors LPAR1/3 ameliorates lung fibrosis induced by irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Gan, Lu [State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu (China); Xue, Jian-Xin [Department of Thoracic Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu (China); Laboratory of Stem Cell Biology, West China Hospital, Sichuan University, Chengdu (China); Li, Xin [Department of Thoracic Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu (China); Liu, De-Song [Department of Pediatrics, Sichuan Provincial Hospital of Women and Children, Chengdu (China); Ge, Yan; Ni, Pei-Yan; Deng, Lin [State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu (China); Lu, You, E-mail: radyoulu@hotmail.com [State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu (China); Department of Thoracic Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu (China); Jiang, Wei, E-mail: wcumsjw72@hotmail.com [State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu (China); Molecular Medicine Research Center, West China Hospital, Sichuan University, Chengdu (China)

    2011-05-27

    Highlights: {yields} Lysophosphatidic acid (LPA) levels and its receptors LPAR1/3 transcripts were elevated during the development of radiation-induced lung fibrosis. {yields} Lung fibrosis was obviously alleviated in mice treated with the dual LPAR1/3 antagonist, VPC12249. {yields} VPC12249 administration effectively inhibited radiation-induced fibroblast accumulation in vivo, and suppressed LPA-induced fibroblast proliferation in vitro. {yields} LPA-LPAR1/3 signaling regulated TGF{beta}1 and CTGF expressions in radiation-challenged lungs, but only influenced CTGF expression in cultured fibroblasts. {yields} LPA-LPAR1/3 signaling induced fibroblast proliferation through a CTGF-dependent pathway, rather than through TGF{beta}1 activation. -- Abstract: Lung fibrosis is a common and serious complication of radiation therapy for lung cancer, for which there are no efficient treatments. Emerging evidence indicates that lysophosphatidic acid (LPA) and its receptors (LPARs) are involved in the pathogenesis of fibrosis. Here, we reported that thoracic radiation with 16 Gy in mice induced development of radiation lung fibrosis (RLF) accompanied by obvious increases in LPA release and LPAR1 and LPAR3 (LPAR1/3) transcripts. RLF was significantly alleviated in mice treated with the dual LPAR1/3 antagonist, VPC12249. VPC12249 administration effectively prolonged animal survival, restored lung structure, inhibited fibroblast accumulation and reduced collagen deposition. Moreover, profibrotic cytokines in radiation-challenged lungs obviously decreased following administration of VPC12249, including transforming growth factor {beta}1 (TGF{beta}1) and connective tissue growth factor (CTGF). In vitro, LPA induced both fibroblast proliferation and CTGF expression in a dose-dependent manner, and both were suppressed by blockade of LPAR1/3. The pro-proliferative activity of LPA on fibroblasts was inhibited by siRNA directed against CTGF. Together, our data suggest that the LPA-LPAR1

  11. Structural alterations of transforming growth factor-beta receptor genes in human cervical carcinoma

    NARCIS (Netherlands)

    Chen, TP; De Vries, EGE; Hollema, H; Yegen, HA; Vellucci, VF; Strickler, HD; Hildesheim, A; Reiss, M

    1999-01-01

    The development and progression of invasive uterine cervical carcinomas appear to be associated with the progressive loss of sensitivity to transforming growth factor-beta (TGF beta)-mediated cell cycle arrest. In order to identify possible molecular mechanisms responsible for TGF beta resistance, w

  12. Structural model for gamma-aminobutyric acid receptor noncompetitive antagonist binding: widely diverse structures fit the same site.

    Science.gov (United States)

    Chen, Ligong; Durkin, Kathleen A; Casida, John E

    2006-03-28

    Several major insecticides, including alpha-endosulfan, lindane, and fipronil, and the botanical picrotoxinin are noncompetitive antagonists (NCAs) for the GABA receptor. We showed earlier that human beta(3) homopentameric GABA(A) receptor recognizes all of the important GABAergic insecticides and reproduces the high insecticide sensitivity and structure-activity relationships of the native insect receptor. Despite large structural diversity, the NCAs are proposed to fit a single binding site in the chloride channel lumen lined by five transmembrane 2 segments. This hypothesis is examined with the beta(3) homopentamer by mutagenesis, pore structure studies, NCA binding, and molecular modeling. The 15 amino acids in the cytoplasmic half of the pore were mutated to cysteine, serine, or other residue for 22 mutants overall. Localization of A-1'C, A2'C, T6'C, and L9'C (index numbers for the transmembrane 2 region) in the channel lumen was established by disulfide cross-linking. Binding of two NCA radioligands [(3)H]1-(4-ethynylphenyl)-4-n-propyl-2,6,7-trioxabicyclo[2.2.2]octane and [(3)H] 3,3-bis-trifluoromethyl-bicyclo[2,2,1]heptane-2,2-dicarbonitrile was dramatically reduced with 8 of the 15 mutated positions, focusing attention on A2', T6', and L9' as proposed binding sites, consistent with earlier mutagenesis studies. The cytoplasmic half of the beta3 homopentamer pore was modeled as an alpha-helix. The six NCAs listed above plus t-butylbicyclophosphorothionate fit the 2' to 9' pore region forming hydrogen bonds with the T6' hydroxyl and hydrophobic interactions with A2', T6', and L9' alkyl substituents, thereby blocking the channel. Thus, widely diverse NCA structures fit the same GABA receptor beta subunit site with important implications for insecticide cross-resistance and selective toxicity between insects and mammals.

  13. Molecular Characterization and Expression Analysis of Adrenergic Receptor Beta 2 (ADRB2) Gene before and after Exercise in the Horse

    OpenAIRE

    Cho, Hyun-Woo; Shin, Sangsu; Song, Ki-Duk; Park, Jeong-woong; Choi, Jae-Young; Lee, Hak-Kyo; Cho, Byung-Wook

    2015-01-01

    The adrenergic receptor beta 2 (ADRB2) plays a role in various physiological responses of the muscle to exercise, such as contraction and relaxation. Given its important role in muscle function, we investigated the structure of the horse ADRB2 gene and its expression pattern after exercise to determine if it can serve as a putative biomarker for recovery. Evolutionary analyses using synonymous and non-synonymous mutation ratios, were compared with other species (human, chimpanzee, mouse, rat,...

  14. Bile Acids Trigger GLP-1 Release Predominantly by Accessing Basolaterally Located G Protein-Coupled Bile Acid Receptors

    DEFF Research Database (Denmark)

    Brighton, Cheryl A.; Rievaj, Juraj; Kuhre, Rune E.;

    2015-01-01

    Bile acids are well-recognized stimuli of glucagon-like peptide-1 (GLP-1) secretion. This action has been attributed to activation of the G protein-coupled bile acid receptor GPBAR1 (TGR5), although other potential bile acid sensors include the nuclear farnesoid receptor and the apical sodium...

  15. Design, synthesis, and evaluation of 2 beta-alkenyl penam sulfone acids as inhibitors of beta-lactamases.

    Science.gov (United States)

    Richter, H G; Angehrn, P; Hubschwerlen, C; Kania, M; Page, M G; Specklin, J L; Winkler, F K

    1996-09-13

    A general method for synthesis of 2 beta-alkenyl penam sulfones has been developed. The new compounds inhibited most of the common types of beta-lactamase. The level of activity depended very strongly on the nature of the substituent in the 2 beta-alkenyl group. The inhibited species formed with the beta-lactamase from Citrobacter freundii 1205 was sufficiently stable for X-ray crystallographic studies. These, together with UV absorption spectroscopy and studies of chemical degradation, suggested a novel reaction mechanism for the new inhibitors that might account for their broad spectrum of action. The (Z)-2 beta-acrylonitrile penam sulfone Ro 48-1220 was the most active inhibitor from this class of compound. The inhibitor enhanced the action of, for example, ceftriaxone against a broad selection of organisms producing beta-lactamases. The organisms included strains of Enterobacteriaceae that produce cephalosporinases, which is an exceptional activity for penam sulfones.

  16. Effect of clavulanic acid on activity of beta-lactam antibiotics in Serratia marcescens isolates producing both a TEM beta-lactamase and a chromosomal cephalosporinase.

    Science.gov (United States)

    Bush, K; Flamm, R K; Ohringer, S; Singer, S B; Summerill, R; Bonner, D P

    1991-01-01

    An isolate of Serratia marcescens that produced both an inducible chromosomal and a plasmid-mediated TEM-1 beta-lactamase was resistant to ampicillin and amoxicillin and also demonstrated decreased susceptibility to extended-spectrum beta-lactam antibiotics (ESBAs). Clavulanic acid did not lower the MICs of the ESBAs, but it decreased the MICs of the penicillins. The TEM-1-producing plasmid was transferred to a more susceptible S. marcescens strain that produced a well-characterized inducible chromosomal beta-lactamase. The MICs of the ESBAs remained at a low level for the transconjugant. Ampicillin and amoxicillin which were good substrates for the plasmid-mediated enzyme, were not well hydrolyzed by the chromosomal enzymes; the ESBAs were hydrolyzed slowly by all the enzymes. When each of the S. marcescens strains was grown with these beta-lactam antibiotics, at least modest increases in chromosomal beta-lactamase activity were observed. When organisms were grown in the presence of clavulanic acid and an ESBA, no enhanced induction was observed. The increases in the MICs of the ESBAs observed for the initial clinical isolate may have been due to a combination of low inducibility, slow hydrolysis, and differences in permeability between the S. marcescens isolates. When clavulanic acid and a penicillin were added to strains that produced both a plasmid-mediated TEM and a chromosomal beta-lactamase, much higher levels of chromosomal beta-lactamase activity were present than were observed in cultures induced by the penicillin alone. This was due to the higher levels of penicillin that were available for induction as a result of inhibition of the TEM enzyme by clavulanate. Images PMID:1803992

  17. Inactivation of the transforming growth factor beta type II receptor in human small cell lung cancer cell lines

    DEFF Research Database (Denmark)

    Hougaard, S; Nørgaard, P; Abrahamsen, N;

    1999-01-01

    Transforming growth factor beta (TGF-beta) exerts a growth inhibitory effect on many cell types through binding to two types of receptors, the type I and II receptors. Resistance to TGF-beta due to lack of type II receptor (RII) has been described in some cancer types including small cell lung...... cancer (SCLC). The purpose of this study was to examine the cause of absent RII expression in SCLC cell lines. Northern blot analysis showed that RII RNA expression was very weak in 16 of 21 cell lines. To investigate if the absence of RII transcript was due to mutations, we screened the poly-A tract...... of the mutation, which has not previously been observed in RII, has been linked to exposure to benzo[a]-pyrene, a component of cigarette smoke. Since RII has been mapped to chromosome 3p22 and nearby loci are often hypermethylated in SCLC, it was examined whether the lack of RII expression was due...

  18. Analysis of the GM-CSF and GM-CSF/IL-3/IL-5 receptor common beta chain in a patient with pulmonary alveolar proteinosis

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Objective To investigate the expression of the granulocyte-macrophage colony-stimulating factor (GM-CSF) and GM-CSF/IL-3/IL-5 receptor common beta chain (βc receptor) in an adult patient with idiopathic pulmonary alveolar proteinosis (PAP), so as to demonstrate the possible association of the GM-CSF and βc receptor with the pathogenesis of human PAP. Methods The GM-CSF levels were measured with a commercial ELISA kit (sensitivity 5?pg/ml) and the βc receptor expression on the cell surface was detected by flow cytometry analysis. Reverse transcription-polymerase chain reaction (RT-PCR) analysis was employed to detect the expression of the GM-CSF mRNA and the βc receptor mRNA in peripheral blood mononuclear cells and alveolar macrophages. The entire coding regions of the GM-CSF cDNA and the βc receptor cDNA were sequenced by the Sanger dideoxy-mediated chain termination method to detect possible mutations. Results The patient with PAP failed to release the GM-CSF protein either from circulating mononuclear cells or from alveolar macrophages. The expression of the GM-CSF mRNA was normal after the stimulation of lipopolysaccharide, whereas a point mutation at position 382 of the GM-CSF cDNA from “T" to “C" was revealed by cDNA sequencing, which caused a change in amino acid 117 of the protein from isoleucine to threonine. The βc receptor expression on the cell surface was normal, and the βc receptor mRNA expression and the sequence of the entire coding region of the βc receptor were also normal. Conclusions The decreased GM-CSF production is associated with the pathogenesis of human PAP. A point mutation of the GM-CSF cDNA may contribute to the decreased GM-CSF production in our adult PAP patient. The mutation of the βc receptor in some of paediatric patients with PAP may not be a common problem in adult patients.

  19. The effect of folic acid on GABA(A)-B 1 receptor subunit.

    Science.gov (United States)

    Vasquez, Kizzy; Kuizon, Salomon; Junaid, Mohammed; Idrissi, Abdeslem El

    2013-01-01

    Autism contains a spectrum of behavioral and cognitive disturbances of childhood development that is manifested by deficits in social interaction, impaired communication, repetitive behavior, and/or restricted interest. Much research has been dedicated to finding the genes that are responsible for autism, but less than 10% of the cases can be attributed to one gene. Autism prevalence has increased in the last decade and there may be environmental components that are leading to this increase. There are reports of disruption of epigenetic mechanisms controlling the regulation of gene expression as probable cause for autism. Folic acid (FA) is prescribed to women during pregnancy, and can cause epigenetic changes. GABAergic pathway is involved in inhibitory neurotransmission in the central nervous system and plays a crucial role during early embryonic development. Autism may entail defect or deregulation of the GABAergic receptor pathway in the brain. Gamma-aminobutyric acid (type A) beta 1 receptor (GABRB1) disruption has been implicated in autism. In the present study, we investigated GABRB1 expression in response to FA supplementation in neuronal cells. Western blot analysis showed GABRB1 protein levels increased in the FA-treated cells in a concentration-dependent manner. FA-dependent increased expression of GABRB1 was further confirmed at the mRNA level using quantitative RT-PCR. These results suggest that epigenetic control of gene expression may affect the expression of GABRB1 and disrupt inhibitory synaptic transmission during embryonic development. PMID:23392927

  20. Ascorbic acid recycling by cultured beta cells: effects of increased glucose metabolism.

    Science.gov (United States)

    Steffner, Robert J; Wu, Lan; Powers, Alvin C; May, James M

    2004-11-15

    Ascorbic acid is necessary for optimal insulin secretion from pancreatic islets. We evaluated ascorbate recycling and whether it is impaired by increased glucose metabolism in the rat beta-cell line INS-1. INS-1 cells, engineered with the potential for overexpression of glucokinase under the control of a tetracycline-inducible gene expression system, took up and reduced dehydroascorbic acid to ascorbate in a concentration-dependent manner that was optimal in the presence of physiologic D-glucose concentrations. Ascorbate uptake did not affect intracellular GSH concentrations. Whereas depletion of GSH in culture to levels about 25% of normal also did not affect the ability of the cells to reduce dehydroascorbic acid, more severe acute GSH depletion to less than 10% of normal levels did impair dehydroascorbic acid reduction. Culture of inducible cells in 11.8 mM D-glucose and doxycycline for 48 h enhanced glucokinase activity, increased glucose utilization, abolished D-glucose-dependent insulin secretion, and increased generation of reactive oxygen species. The latter may have contributed to subsequent decreases in the ability of the cells both to maintain intracellular ascorbate and to recycle it from dehydroascorbic acid. Cultured beta cells have a high capacity to recycle ascorbate, but this is sensitive to oxidant stress generated by increased glucose metabolism due to culture in high glucose concentrations and increased glucokinase expression. Impaired ascorbate recycling as a result of increased glucose metabolism may have implications for the role of ascorbate in insulin secretion in diabetes mellitus and may partially explain glucose toxicity in beta cells. PMID:15477012

  1. Pancreatic beta-cell overexpression of the glucagon receptor gene results in enhanced beta-cell function and mass

    DEFF Research Database (Denmark)

    Gelling, Richard W; Vuguin, Patricia M; Du, Xiu Quan;

    2009-01-01

    In addition to its primary role in regulating glucose production from the liver, glucagon has many other actions, reflected by the wide tissue distribution of the glucagon receptor (Gcgr). To investigate the role of glucagon in the regulation of insulin secretion and whole body glucose homeostasi...

  2. Plasmin-induced migration requires signaling through protease-activated receptor 1 and integrin alpha(9)beta(1).

    Science.gov (United States)

    Majumdar, Mousumi; Tarui, Takehiko; Shi, Biao; Akakura, Nobuaki; Ruf, Wolfram; Takada, Yoshikazu

    2004-09-01

    Plasmin is a major extracellular protease that elicits intracellular signals to mediate platelet aggregation, chemotaxis of peripheral blood monocytes, and release of arachidonate and leukotriene from several cell types in a G protein-dependent manner. Angiostatin, a fragment of plasmin(ogen), is a ligand and an antagonist for integrin alpha(9)beta(1). Here we report that plasmin specifically interacts with alpha(9)beta(1) and that plasmin induces of cells expressing migration recombinant alpha(9)beta(1) (alpha(9)-Chinese hamster ovary (CHO) cells). Migration was dependent on an interaction of the kringle domains of plasmin with alpha(9)beta(1) as well as the catalytic activity of plasmin. Angiostatin, representing the kringle domains of plasmin, alone did not induce the migration of alpha(9)-CHO cells, but simultaneous activation of the G protein-coupled protease-activated receptor (PAR)-1 with an agonist peptide induced the migration on angiostatin, whereas PAR-2 or PAR-4 agonist peptides were without effect. Furthermore, a small chemical inhibitor of PAR-1 (RWJ 58259) and a palmitoylated PAR-1-blocking peptide inhibited plasmin-induced migration of alpha(9)-CHO cells. These results suggest that plasmin induces migration by kringle-mediated binding to alpha(9)beta(1) and simultaneous proteolytic activation of PAR-1. PMID:15247268

  3. Studies of the associations between functional beta2-adrenergic receptor variants and obesity, hypertension and type 2 diabetes in 7,808 white subjects

    DEFF Research Database (Denmark)

    Gjesing, A P; Andersen, G; Burgdorf, K S;

    2007-01-01

    Functional and common Arg16Gly and Gln27Glu polymorphisms have been identified in ADRB2, the gene encoding the beta2-adrenergic receptor. These variants have previously been examined for association with obesity, hypertension and diabetes with inconclusive results.......Functional and common Arg16Gly and Gln27Glu polymorphisms have been identified in ADRB2, the gene encoding the beta2-adrenergic receptor. These variants have previously been examined for association with obesity, hypertension and diabetes with inconclusive results....

  4. Beta-adrenergic receptor agonists induce the release of granulocyte chemotactic protein-2, oncostatin M, and vascular endothelial growth factor from macrophages

    NARCIS (Netherlands)

    Verhoeckx, K.C.; Doornbos, R.P.; Witkamp, R.F.; Greef, J. van der; Rodenburg, R.J.T.

    2006-01-01

    Vascular endothelial growth factor (VEGF), oncostatin M (OSM), and granulocyte chemotactic protein-2 (GCP-2/CXCL6) are up-regulated in U937 macrophages and peripheral blood macrophages exposed to LPS, beta-adrenergic receptor (beta2-AR) agonists (e.g. zilpaterol, and clenbuterol) and some other agen

  5. In vitro bile-acid binding and fermentation of high, medium, and low molecular weight beta-glucan.

    Science.gov (United States)

    Kim, Hyun Jung; White, Pamela J

    2010-01-13

    The impact of beta-glucan molecular weight (MW) on in vitro bile-acid binding and in vitro fermentation with human fecal flora was evaluated. beta-Glucan extracted from oat line 'N979-5-4' was treated with lichenase (1,3-1,4-beta-D-glucanase) to yield high (6.87x10(5) g/mol), medium (3.71x10(5) g/mol), and low (1.56x10(5) g/mol) MW fractions. The low MW beta-glucan bound more bile acid than did the high MW beta-glucan (pbeta-glucan with high, medium, and low MW was 15, 27, 24, and 21%, respectively. Significant effects of high, medium, and low MW beta-glucans on total SCFA were observed compared to the blank without substrate (pbeta-glucans, and lactulose. The low MW beta-glucan produced greater amounts of SCFA than the high MW after 24 h of fermentation. Among the major SCFA, more propionate was produced from all MW fractions of extracted beta-glucans than from lactulose. In vitro fermentation of extracted beta-glucan fractions with different MW lowered pH and produced SCFA, providing potential biological function. PMID:20020684

  6. Development of novel silicon-containing inverse agonists of retinoic acid receptor-related orphan receptors.

    Science.gov (United States)

    Toyama, Hirozumi; Nakamura, Masaharu; Nakamura, Masahiko; Matsumoto, Yotaro; Nakagomi, Madoka; Hashimoto, Yuichi

    2014-03-15

    Retinoic acid receptor (RAR)-related orphan receptors (RORs) regulate a variety of physiological processes, including hepatic gluconeogenesis, lipid metabolism, circadian rhythm and immune function. The RAR agonist: all-trans retinoic acid was reported to be an RORβ inverse agonist, but no information is available regarding ROR activity of its synthetic analogue Am580. Therefore, we screened Am580 and some related tetramethyltetrahydronaphthalene derivatives and carried out structural development studies, including substitution of carbon atoms with silicon, with the aim of creating a potent ROR transcriptional inhibitor. The phenyl amide disila compound 22 showed the most potent ROR-inhibitory activity among the compounds examined. Its activity towards RORα, RORβ and RORγ was increased compared to that of Am580. The IC₅₀ values for RORα, RORβ and RORγ are 1.3, >10 and 4.5 μM, respectively.

  7. A novel missense mutation in oncostatin M receptor beta causing primary localized cutaneous amyloidosis.

    Science.gov (United States)

    Saeedi, Marjan; Ebrahim-Habibi, Azadeh; Haghighi, Alireza; Zarrabi, Fariba; Amoli, Mahsa M; Robati, Reza M

    2014-01-01

    Primary localized cutaneous amyloidosis (PLCA) is a chronic skin disorder, caused by amyloid material deposition in the upper dermis. Autosomal dominant PLCA has been mapped earlier to pathogenic missense mutations in the OSMR gene, which encodes the oncostatin M receptor ß subunit (OSMRß). OSMRß is interleukin-6 family cytokine receptors and possesses two ligands, oncostatin M and interleukin-31, which both have biologic roles in inflammation and keratinocyte cell proliferation, differentiation, and apoptosis. Here, we identified a new OSMR mutation in a Kurdish family for the first time. Blood samples were taken from all the affected individuals in the family. DNA extraction was performed using salting out technique. Primers were designed for intron flanking individual exons of OSMR gene which were subjected to direct sequencing after PCR amplification for each sample. Sequencing showed a C/T substitution at position 613 in the proband. This mutation results in an L613S (leucine 613 to serine) amino acid change. The identified mutation was observed in all affected family members but not in 100 ethnically matched healthy controls. Elucidating the molecular basis of familial PLCA provides new insight into mechanisms of itch in human skin and may lead to new therapeutic targets for pruritus. PMID:25054142

  8. A Novel Missense Mutation in Oncostatin M Receptor Beta Causing Primary Localized Cutaneous Amyloidosis

    Directory of Open Access Journals (Sweden)

    Marjan Saeedi

    2014-01-01

    Full Text Available Primary localized cutaneous amyloidosis (PLCA is a chronic skin disorder, caused by amyloid material deposition in the upper dermis. Autosomal dominant PLCA has been mapped earlier to pathogenic missense mutations in the OSMR gene, which encodes the oncostatin M receptor ß subunit (OSMRß. OSMRß is interleukin-6 family cytokine receptors and possesses two ligands, oncostatin M and interleukin-31, which both have biologic roles in inflammation and keratinocyte cell proliferation, differentiation, and apoptosis. Here, we identified a new OSMR mutation in a Kurdish family for the first time. Blood samples were taken from all the affected individuals in the family. DNA extraction was performed using salting out technique. Primers were designed for intron flanking individual exons of OSMR gene which were subjected to direct sequencing after PCR amplification for each sample. Sequencing showed a C/T substitution at position 613 in the proband. This mutation results in an L613S (leucine 613 to serine amino acid change. The identified mutation was observed in all affected family members but not in 100 ethnically matched healthy controls. Elucidating the molecular basis of familial PLCA provides new insight into mechanisms of itch in human skin and may lead to new therapeutic targets for pruritus.

  9. Hyaluronic acid induces activation of the κ-opioid receptor.

    Directory of Open Access Journals (Sweden)

    Barbara Zavan

    Full Text Available INTRODUCTION: Nociceptive pain is one of the most common types of pain that originates from an injury involving nociceptors. Approximately 60% of the knee joint innervations are classified as nociceptive. The specific biological mechanism underlying the regulation of nociceptors is relevant for the treatment of symptoms affecting the knee joint. Intra-articular administration of exogenous hyaluronic acid (HA in patients with osteoarthritis (OA appears to be particularly effective in reducing pain and improving patient function. METHODS: We performed an in vitro study conducted in CHO cells that expressed a panel of opioid receptors and in primary rat dorsal root ganglion (DRG neurons to determine if HA induces the activation of opioid peptide receptors (OPr using both aequorin and the fluorescent dye Fura-2/AM. RESULTS: Selective agonists and antagonists for each OPr expressed on CHO cells were used to test the efficacy of our in vitro model followed by stimulation with HA. The results showed that HA induces stimulatory effects on the κ receptor (KOP. These effects of HA were also confirmed in rat DRG neurons, which express endogenously the OPr. CONCLUSIONS: HA activates the KOP receptor in a concentration dependent manner, with a pEC(50 value of 7.57.

  10. Thyroid hormone receptor can modulate retinoic acid-mediated axis formation in frog embryogenesis.

    OpenAIRE

    Banker, D E; Eisenman, R N

    1993-01-01

    Thyroid hormone receptor acts as a hormone-dependent transcriptional transactivator and as a transcriptional repressor in the absence of thyroid hormone. Specifically, thyroid hormone receptor can repress retinoic acid-induced gene expression through interactions with retinoic acid receptor. (Retinoic acid is a potent teratogen in the frog Xenopus laevis, acting at early embryonic stages to interfere with the formation of anterior structures. Endogenous retinoic acid is thought to act in norm...

  11. beta-TrCP inhibition reduces prostate cancer cell growth via upregulation of the aryl hydrocarbon receptor.

    Directory of Open Access Journals (Sweden)

    Udi Gluschnaider

    Full Text Available BACKGROUND: Prostate cancer is a common and heterogeneous disease, where androgen receptor (AR signaling plays a pivotal role in development and progression. The initial treatment for advanced prostate cancer is suppression of androgen signaling. Later on, essentially all patients develop an androgen independent stage which does not respond to anti hormonal treatment. Thus, alternative strategies targeting novel molecular mechanisms are required. beta-TrCP is an E3 ligase that targets various substrates essential for many aspects of tumorigenesis. METHODOLOGY/PRINCIPAL FINDINGS: Here we show that beta-TrCP depletion suppresses prostate cancer and identify a relevant growth control mechanism. shRNA targeted against beta-TrCP reduced prostate cancer cell growth and cooperated with androgen ablation in vitro and in vivo. We found that beta-TrCP inhibition leads to upregulation of the aryl hydrocarbon receptor (AhR mediating the therapeutic effect. This phenomenon could be ligand independent, as the AhR ligand 2,3,7,8-Tetrachlorodibenzo-p-Dioxin (TCDD did not alter prostate cancer cell growth. We detected high AhR expression and activation in basal cells and atrophic epithelial cells of human cancer bearing prostates. AhR expression and activation is also significantly higher in tumor cells compared to benign glandular epithelium. CONCLUSIONS/SIGNIFICANCE: Together these observations suggest that AhR activation may be a cancer counteracting mechanism in the prostate. We maintain that combining beta-TrCP inhibition with androgen ablation could benefit advanced prostate cancer patients.

  12. Transforming growth factor beta receptor II polymorphisms are associated with Kawasaki disease

    Directory of Open Access Journals (Sweden)

    Yu Mi Choi

    2012-01-01

    Full Text Available Purpose : Transforming growth factor beta receptor 2 (TGFBR2 is a tumor suppressor gene that plays a role in the differentiation of striated cells and remodeling of coronary arteries. Single nucleotide polymorphisms (SNPs of this gene are associated with Marfan syndrome and sudden death in patients with coronary artery disease. Cardiovascular remodeling and T cell activation of TGFBR2 gene suggest that the TGFBR2 gene SNPs are related to the pathogenesis of Kawasaki disease (KD and coronary artery lesion (CAL. Methods : The subjects were 105 patients with KD and 500 healthy adults as controls. Mean age of KD group was 32 months age and 26.6% of those had CAL. We selected TGFBR2 gene SNPs from serum and performed direct sequencing. Results : The sequences of the eleven SNPs in the TGFBR2 gene were compared between the KD group and controls. Three SNPs (rs1495592, rs6550004, rs795430 were associated with development of KD (P=0.019, P=0.026, P=0.016, respectively. One SNP (rs1495592 was associated with CAL in KD group (P=0.022. Conclusion : Eleven SNPs in TGFBR2 gene were identified at that time the genome wide association. But, with the change of the data base, only six SNPs remained associated with the TGFBR2 gene. One of the six SNPs (rs6550004 was associated with development of KD. One SNP associated with CAL (rs1495592 was disassociated from the TGFBR2 gene. The other five SNPs were not functionally identified, but these SNPs are notable because the data base is changing. Further studies involving larger group of patients with KD are needed.

  13. ChREBP Mediates Glucose Repression of Peroxisome Proliferator-activated Receptor {alpha} Expression in Pancreatic {beta}-Cells

    DEFF Research Database (Denmark)

    Boergesen, Michael; Poulsen, Lars la Cour; Schmidt, Søren Fisker;

    2011-01-01

    Chronic exposure to elevated levels of glucose and fatty acids leads to dysfunction of pancreatic β-cells by mechanisms that are only partly understood. The transcription factor peroxisome proliferator-activated receptor α (PPARα) is an important regulator of genes involved in fatty acid metaboli...... of glucose repression of PPARα gene expression in pancreatic β-cells, suggesting that ChREBP may be important for glucose suppression of the fatty acid oxidation capacity of β-cells....

  14. Tetrazolyl isoxazole amino acids as ionotropic glutamate receptor antagonists: synthesis, modelling and molecular pharmacology

    DEFF Research Database (Denmark)

    Frølund, Bente; Greenwood, Jeremy R; Holm, Mai Marie;

    2005-01-01

    and 1b were pharmacologically characterized in receptor binding assays, and electrophysiologically on homomeric AMPA receptors (GluR1-4), homomeric (GluR5 and GluR6) and heteromeric (GluR6/KA2) kainic acid receptors, using two-electrode voltage-clamped Xenopus laevis oocytes expressing these receptors...

  15. Quinic acids from Aster caucasicus and from transgenic callus expressing a beta-amyrin synthase.

    Science.gov (United States)

    Pecchia, Paola; Cammareri, Maria; Malafronte, Nicola; Consiglio, M Federica; Gualtieri, Maria Josefina; Conicella, Clara

    2011-11-01

    Several different classes of secondary metabolites, including flavonoids, triterpenoid saponins and quinic acid derivatives, are found in Aster spp. (Fam. Asteraceae). Several Aster compounds revealed biological as well as pharmacological activities. In this work, a phytochemical investigation of A. caucasicus evidenced the presence of quinic acid derivatives, as well as the absence of triterpene saponins. To combine in one species the production of different phytochemicals, including triterpenes, an Agrobacterium-mediated transformation of A. caucasicus was set up to introduce A. sedifolius beta-amyrin synthase (AsOXA1)-encoding gene under the control of the constitutive promoter CaMV35S. The quali-quantitative analysis of transgenic calli with ectopic expression of AsOXA1 showed, in one sample, a negligible amount of triterpene saponins combined with higher amount of quinic acid derivatives as compared with the wild type callus. PMID:22224284

  16. Histochemical demonstration of activity of acid phosphatase and beta-glucuronidase in bovine incisor tooth germs

    DEFF Research Database (Denmark)

    Kirkeby, S; Salling, E; Moe, D

    1983-01-01

    Activity of acid phosphatase and beta-glucuronidase was shown in bovine preodontoblasts and preameloblasts prior to the onset of secretion. In the preameloblasts the rather weak reaction consisted of small discrete granules dispersed in the cytoplasm apical, lateral, and proximal to the nucleus....... After initiation of enamel formation, a change in localization and intensity of the colored reaction product was observed in the ameloblasts. The activity appeared stronger and was restricted to a narrow zone just apical to the nucleus. It is proposed that the acid hydrolases in the tooth forming cells...... are located to the Golgi complex. The differences in activity of acid hydrolases between bone and tooth forming cells are expounded....

  17. Growth suppression by transforming growth factor beta 1 of human small-cell lung cancer cell lines is associated with expression of the type II receptor

    DEFF Research Database (Denmark)

    Nørgaard, P; Damstrup, L; Rygaard, K;

    1994-01-01

    was observed in two cell lines expressing only type III receptor and in TGF-beta-r negative cell lines. In two cell lines expressing all three receptor types, growth suppression was accompanied by morphological changes. To evaluate the possible involvement of the retinoblastoma protein (pRb) in mediating...... the growth-suppressive effect of TGF-beta 1, the expression of functional pRb, as characterised by nuclear localisation, was examined by immunocytochemistry. Nuclear association of pRb was only seen in two of the five TGF-beta 1-responsive cell lines. These results indicate that in SCLC pRb is not required...

  18. Bile Acids Trigger GLP-1 Release Predominantly by Accessing Basolaterally Located G Protein–Coupled Bile Acid Receptors

    OpenAIRE

    Brighton, Cheryl A.; Rievaj, Juraj; Kuhre, Rune E; Glass, Leslie L; Schoonjans, Kristina; Holst, Jens J.; Gribble, Fiona M.; Reimann, Frank

    2015-01-01

    Bile acids are well-recognized stimuli of glucagon-like peptide-1 (GLP-1) secretion. This action has been attributed to activation of the G protein–coupled bile acid receptor GPBAR1 (TGR5), although other potential bile acid sensors include the nuclear farnesoid receptor and the apical sodium-coupled bile acid transporter ASBT. The aim of this study was to identify pathways important for GLP-1 release and to determine whether bile acids target their receptors on GLP-1–secreting L-cells from t...

  19. Susceptibility of pancreatic beta cells to fatty acids is regulated by LXR/PPARalpha-dependent stearoyl-coenzyme A desaturase.

    Directory of Open Access Journals (Sweden)

    Karine H Hellemans

    Full Text Available Chronically elevated levels of fatty acids-FA can cause beta cell death in vitro. Beta cells vary in their individual susceptibility to FA-toxicity. Rat beta cells were previously shown to better resist FA-toxicity in conditions that increased triglyceride formation or mitochondrial and peroxisomal FA-oxidation, possibly reducing cytoplasmic levels of toxic FA-moieties. We now show that stearoyl-CoA desaturase-SCD is involved in this cytoprotective mechanism through its ability to transfer saturated FA into monounsaturated FA that are incorporated in lipids. In purified beta cells, SCD expression was induced by LXR- and PPARalpha-agonists, which were found to protect rat, mouse and human beta cells against palmitate toxicity. When their SCD was inhibited or silenced, the agonist-induced protection was also suppressed. A correlation between beta cell-SCD expression and susceptibility to palmitate was also found in beta cell preparations isolated from different rodent models. In mice with LXR-deletion (LXRbeta(-/- and LXRalphabeta(-/-, beta cells presented a reduced SCD-expression as well as an increased susceptibility to palmitate-toxicity, which could not be counteracted by LXR or PPARalpha agonists. In Zucker fatty rats and in rats treated with the LXR-agonist TO1317, beta cells show an increased SCD-expression and lower palmitate-toxicity. In the normal rat beta cell population, the subpopulation with lower metabolic responsiveness to glucose exhibits a lower SCD1 expression and a higher susceptibility to palmitate toxicity. These data demonstrate that the beta cell susceptibility to saturated fatty acids can be reduced by stearoyl-coA desaturase, which upon stimulation by LXR and PPARalpha agonists favors their desaturation and subsequent incorporation in neutral lipids.

  20. The repertoire of olfactory C family G protein-coupled receptors in zebrafish: candidate chemosensory receptors for amino acids

    Directory of Open Access Journals (Sweden)

    Ngai John

    2006-12-01

    Full Text Available Abstract Background Vertebrate odorant receptors comprise at least three types of G protein-coupled receptors (GPCRs: the OR, V1R, and V2R/V2R-like receptors, the latter group belonging to the C family of GPCRs. These receptor families are thought to receive chemosensory information from a wide spectrum of odorant and pheromonal cues that influence critical animal behaviors such as feeding, reproduction and other social interactions. Results Using genome database mining and other informatics approaches, we identified and characterized the repertoire of 54 intact "V2R-like" olfactory C family GPCRs in the zebrafish. Phylogenetic analysis – which also included a set of 34 C family GPCRs from fugu – places the fish olfactory receptors in three major groups, which are related to but clearly distinct from other C family GPCRs, including the calcium sensing receptor, metabotropic glutamate receptors, GABA-B receptor, T1R taste receptors, and the major group of V2R vomeronasal receptor families. Interestingly, an analysis of sequence conservation and selective pressure in the zebrafish receptors revealed the retention of a conserved sequence motif previously shown to be required for ligand binding in other amino acid receptors. Conclusion Based on our findings, we propose that the repertoire of zebrafish olfactory C family GPCRs has evolved to allow the detection and discrimination of a spectrum of amino acid and/or amino acid-based compounds, which are potent olfactory cues in fish. Furthermore, as the major groups of fish receptors and mammalian V2R receptors appear to have diverged significantly from a common ancestral gene(s, these receptors likely mediate chemosensation of different classes of chemical structures by their respective organisms.

  1. Specific in vitro toxicity of crude and refined petroleum products: II. Estrogen (alpha and beta) and androgen receptor-mediated responses in yeast assays.

    NARCIS (Netherlands)

    Vrabie, C.M.; Candido, A.; van Duursen, M.B.M.; Jonker, M.T.O.

    2010-01-01

    The present study is the second in a series aiming at a systematic inventory of specific toxic effects of oils. By employing a recombinant yeast stably transfected with human estrogen receptor-alpha (ERalpha) or -beta (ERbeta) or androgen receptor (AR) and expressing yeast enhanced green fluorescent

  2. Human-Specific SNP in Obesity Genes, Adrenergic Receptor Beta2 (ADRB2), Beta3 (ADRB3), and PPAR γ2 (PPARG), during Primate Evolution

    Science.gov (United States)

    Takenaka, Akiko; Nakamura, Shin; Mitsunaga, Fusako; Inoue-Murayama, Miho; Udono, Toshifumi; Suryobroto, Bambang

    2012-01-01

    Adrenergic-receptor beta2 (ADRB2) and beta3 (ADRB3) are obesity genes that play a key role in the regulation of energy balance by increasing lipolysis and thermogenesis. The Glu27 allele in ADRB2 and the Arg64 allele in ADRB3 are associated with abdominal obesity and early onset of non-insulin-dependent diabetes mellitus (NIDDM) in many ethnic groups. Peroxisome proliferator-activated receptor γ (PPARG) is required for adipocyte differentiation. Pro12Ala mutation decreases PPARG activity and resistance to NIDDM. In humans, energy-expense alleles, Gln27 in ADRB2 and Trp64 in ADRB3, are at higher frequencies than Glu27 and Arg64, respectively, but Ala12 in PPARG is at lower frequency than Pro12. Adaptation of humans for lipolysis, thermogenesis, and reduction of fat accumulation could be considered by examining which alleles in these genes are dominant in non-human primates (NHP). All NHP (P. troglodytes, G. gorilla, P. pygmaeus, H. agilis and macaques) had energy-thrifty alleles, Gly16 and Glu27 in ADRB2, and Arg64 in ADRB3, but did not have energy-expense alleles, Arg16, Gln27 and Trp64 alleles. In PPARG gene, all NHP had large adipocyte accumulating type, the Pro12 allele. Conclusions These results indicate that a tendency to produce much more heat through the energy-expense alleles developed only in humans, who left tropical rainforests for savanna and developed new features in their heat-regulation systems, such as reduction of body hair and increased evaporation of water, and might have helped the protection of entrails from cold at night, especially in glacial periods. PMID:22937051

  3. Human-specific SNP in obesity genes, adrenergic receptor beta2 (ADRB2, Beta3 (ADRB3, and PPAR γ2 (PPARG, during primate evolution.

    Directory of Open Access Journals (Sweden)

    Akiko Takenaka

    Full Text Available UNLABELLED: Adrenergic-receptor beta2 (ADRB2 and beta3 (ADRB3 are obesity genes that play a key role in the regulation of energy balance by increasing lipolysis and thermogenesis. The Glu27 allele in ADRB2 and the Arg64 allele in ADRB3 are associated with abdominal obesity and early onset of non-insulin-dependent diabetes mellitus (NIDDM in many ethnic groups. Peroxisome proliferator-activated receptor γ (PPARG is required for adipocyte differentiation. Pro12Ala mutation decreases PPARG activity and resistance to NIDDM. In humans, energy-expense alleles, Gln27 in ADRB2 and Trp64 in ADRB3, are at higher frequencies than Glu27 and Arg64, respectively, but Ala12 in PPARG is at lower frequency than Pro12. Adaptation of humans for lipolysis, thermogenesis, and reduction of fat accumulation could be considered by examining which alleles in these genes are dominant in non-human primates (NHP. All NHP (P. troglodytes, G. gorilla, P. pygmaeus, H. agilis and macaques had energy-thrifty alleles, Gly16 and Glu27 in ADRB2, and Arg64 in ADRB3, but did not have energy-expense alleles, Arg16, Gln27 and Trp64 alleles. In PPARG gene, all NHP had large adipocyte accumulating type, the Pro12 allele. CONCLUSIONS: These results indicate that a tendency to produce much more heat through the energy-expense alleles developed only in humans, who left tropical rainforests for savanna and developed new features in their heat-regulation systems, such as reduction of body hair and increased evaporation of water, and might have helped the protection of entrails from cold at night, especially in glacial periods.

  4. Treatment of type 2 diabetes by free Fatty Acid receptor agonists

    DEFF Research Database (Denmark)

    Watterson, Kenneth R; Hudson, Brian D; Ulven, Trond;

    2014-01-01

    Dietary free fatty acids (FFAs), such as ω-3 fatty acids, regulate metabolic and anti-inflammatory processes, with many of these effects attributed to FFAs interacting with a family of G protein-coupled receptors. Selective synthetic ligands for free fatty acid receptors (FFA1-4) have consequently...

  5. RAGE is a nucleic acid receptor that promotes inflammatory responses to DNA

    OpenAIRE

    Sirois, Cherilyn M.; Jin, Tengchuan; Miller, Allison L.; Bertheloot, Damien; Nakamura, Hirotaka; Horvath, Gabor L.; Mian, Abubakar; Jiang, Jiansheng; Schrum, Jacob; Bossaller, Lukas; Pelka, Karin; Garbi, Natalio; Brewah, Yambasu; Tian, Jane; Chang, ChewShun

    2013-01-01

    Recognition of DNA and RNA molecules derived from pathogens or self-antigen is one way the mammalian immune system senses infection and tissue damage. Activation of immune signaling receptors by nucleic acids is controlled by limiting the access of DNA and RNA to intracellular receptors, but the mechanisms by which endosome-resident receptors encounter nucleic acids from the extracellular space are largely undefined. In this study, we show that the receptor for advanced glycation end-products...

  6. Interaction of the C-terminal acidic domain of the insulin receptor with histone modulates the receptor kinase activity.

    Science.gov (United States)

    Baron, V; Kaliman, P; Alengrin, F; Van Obberghen, E

    1995-04-01

    In this study, we investigated the role of the insulin receptor domain 1270-1280, an acid-rich sequence located in the receptor C-terminus. Antipeptide IgG raised against this sequence were obtained and used to analyze their effect on receptor function. Antipeptide IgG inhibited receptor autophosphorylation at Tyr1146, Tyr1150 and Tyr1151. These sites are known to be key modulators of the receptor activity. Autophosphorylation at other sites may also have been inhibited. The antipeptide antibody decreased the receptor kinase activity measured with poly(Glu80Tyr20) and a synthetic peptide corresponding to the proreceptor sequence 1142-1158. We provide evidence that the effect of the antibody on substrate phosphorylation may result from the control of the phosphorylation level of the receptor. Concerning the action of the antipeptide IgG on the receptor kinase activity, histone did not behave similarly to poly(Glu80Tyr20). The antibody recognizing sequence 1270-1280 competed with histone for an overlapping binding site. Histone also modulated insulin receptor autophosphorylation, supporting the idea that interference with domain 1270-1280 alters the receptor kinase. Our data suggest that the acidic region including residues 1270-1280 of the insulin receptor C-terminus is involved in the following events: (a) receptor binding with histone, an exogenous substrate of the receptor kinase, and (b) the regulation of receptor autophosphorylation and kinase activity. Based on these observations, we would like to propose that this insulin receptor domain could interact with cellular proteins modulating the receptor kinase. PMID:7744039

  7. Stereospecific synthesis of threo- and erythro-beta-hydroxyglutamic acid during kutzneride biosynthesis.

    Science.gov (United States)

    Strieker, Matthias; Nolan, Elizabeth M; Walsh, Christopher T; Marahiel, Mohamed A

    2009-09-23

    The antifungal and antimicrobial kutznerides, hexadepsipeptides composed of one alpha-hydroxy acid and five nonproteinogenic amino acids, are remarkable examples of the structural diversity found in nonribosomally produced natural products. They contain D-3-hydroxyglutamic acid, which is found in the threo and erythro isomers in mature kutznerides. In this study, two putative nonheme iron oxygenase enzymes, KtzO and KtzP, were recombinantly expressed, characterized biochemically in vitro, and found to stereospecifically hydroxylate the beta-position of glutamic acid. KtzO generates threo-L-hydroxyglutamic acid and KtzP catalyzes the formation of the erythro-isomer bound to the peptidyl carrier protein of the third module of the nonribosomal peptide synthetase KtzH. This module has a truncated adenylation domain and is unable to activate and incorporate glutamic acid. The lack of a functional adenylation domain in the third KtzH module is compensated in trans by the stand-alone adenylation domain KtzN, which activates and transfers glutamic acid onto the carrier of KtzH in the presence of the truncated adenylation domain and either KtzO or KtzP. A method that employs nonhydrolyzable coenzyme A analogs was developed and used to determine the kinetic parameters for KtzO- and KtzP-catalyzed hydroxylation of glutamic acid bound to the carrier protein. A detailed mechanism for the in trans compensation of the truncated adenylation domain and the stereospecific hydroxyglutamic acid generation and incorporation is presented. These insights may guide the use of KtzO/KtzP and KtzN or other in trans modification/restoration tools in biocombinatorial engineering approaches.

  8. Structural Characterization of the Boca/Mesd Maturation Factors for LDL-Receptor-Type beta Propeller Domains

    Energy Technology Data Exchange (ETDEWEB)

    M Collins; W Hendrickson

    2011-12-31

    Folding and trafficking of low-density lipoprotein receptor (LDLR) family members, which play essential roles in development and homeostasis, are mediated by specific chaperones. The Boca/Mesd chaperone family specifically promotes folding and trafficking of the YWTD {beta} propeller-EGF domain pair found in the ectodomain of all LDLR members. Limited proteolysis, NMR spectroscopy, analytical ultracentrifugation, and X-ray crystallography were used to define a conserved core composed of a structured domain that is preceded by a disordered N-terminal region. High-resolution structures of the ordered domain were determined for homologous proteins from three metazoans. Seven independent protomers reveal a novel ferrodoxin-like superfamily fold with two distinct {beta} sheet topologies. A conserved hydrophobic surface forms a dimer interface in each crystal, but these differ substantially at the atomic level, indicative of nonspecific hydrophobic interactions that may play a role in the chaperone activity of the Boca/Mesd family.

  9. Interleukin 1 (IL-1) type I receptors mediate activation of rat hypothalamus-pituitary-adrenal axis and interleukin 6 production as shown by receptor type selective deletion mutants of IL-1beta.

    Science.gov (United States)

    Van Dam, A M; Malinowsky, D; Lenczowski, M J; Bartfai, T; Tilders, F J

    1998-06-01

    The cytokine interleukin 1 (IL-1) plays an important role in the activation of the hypothalamus-pituary-adrenal (HPA)-axis and interleukin 6 (IL-6) production during infection or inflammation. Which of the interleukin-1 receptor types mediates these effects is not known. To investigate this issue a pharmacological approach was chosen by using recently developed IL-1 receptor type selective ligands. Rats were given one of various doses of recombinant human IL-1beta (rhIL-1beta; 1 and 10 microg/kg) and of several IL-1beta mutants (DeltaSND, DeltaQGE and DeltaI; 1, 10 and 100 microg/kg), that differ in their affinities for the IL-1 type I receptor but have similar affinities for the IL-1 type II receptor. One hour after intravenous administration of rhIL-1beta or IL-1beta mutants, plasma levels of ACTH, corticosterone (cort) and IL-6 were measured. Doses of 1 and 10 microg/kg rhIL-1beta markedly elevated plasma levels of ACTH, cort and IL-6. However, 10-100-fold higher doses of IL-1beta mutants DeltaSND and DeltaQGE and at least 100-fold higher doses of DeltaI have to be administered to increase plasma levels of ACTH, cort and IL-6. The potency differences correlate with their respective affinity for the type I receptor but not with that of the IL-1 type II receptor. It is concluded that IL-1beta induced ACTH, cort and IL-6 production is mediated by interleukin 1 type I receptors.

  10. Retinoic acid receptors: from molecular mechanisms to cancer therapy.

    Science.gov (United States)

    di Masi, Alessandra; Leboffe, Loris; De Marinis, Elisabetta; Pagano, Francesca; Cicconi, Laura; Rochette-Egly, Cécile; Lo-Coco, Francesco; Ascenzi, Paolo; Nervi, Clara

    2015-02-01

    Retinoic acid (RA), the major bioactive metabolite of retinol or vitamin A, induces a spectrum of pleiotropic effects in cell growth and differentiation that are relevant for embryonic development and adult physiology. The RA activity is mediated primarily by members of the retinoic acid receptor (RAR) subfamily, namely RARα, RARβ and RARγ, which belong to the nuclear receptor (NR) superfamily of transcription factors. RARs form heterodimers with members of the retinoid X receptor (RXR) subfamily and act as ligand-regulated transcription factors through binding specific RA response elements (RAREs) located in target genes promoters. RARs also have non-genomic effects and activate kinase signaling pathways, which fine-tune the transcription of the RA target genes. The disruption of RA signaling pathways is thought to underlie the etiology of a number of hematological and non-hematological malignancies, including leukemias, skin cancer, head/neck cancer, lung cancer, breast cancer, ovarian cancer, prostate cancer, renal cell carcinoma, pancreatic cancer, liver cancer, glioblastoma and neuroblastoma. Of note, RA and its derivatives (retinoids) are employed as potential chemotherapeutic or chemopreventive agents because of their differentiation, anti-proliferative, pro-apoptotic, and anti-oxidant effects. In humans, retinoids reverse premalignant epithelial lesions, induce the differentiation of myeloid normal and leukemic cells, and prevent lung, liver, and breast cancer. Here, we provide an overview of the biochemical and molecular mechanisms that regulate the RA and retinoid signaling pathways. Moreover, mechanisms through which deregulation of RA signaling pathways ultimately impact on cancer are examined. Finally, the therapeutic effects of retinoids are reported. PMID:25543955

  11. RXR alpha, a promiscuous partner of retinoic acid and thyroid hormone receptors.

    OpenAIRE

    Bugge, T H; Pohl, J.; Lonnoy, O; Stunnenberg, H G

    1992-01-01

    Retinoic acid receptor (RAR), thyroid hormone receptor (T3R) and vitamin D3 receptor (VD3R) differ from steroid hormone receptors in that they bind and transactivate through responsive elements organized as direct rather than inverted repeats. We now show that recombinant RAR and T3R are monomers in solution and cannot form stable homodimeric complexes on their responsive elements. Stable binding of the receptors to their responsive elements requires heterodimerization with a nuclear factor. ...

  12. Biological roles and therapeutic potential of hydroxy-carboxylic acid receptors

    Directory of Open Access Journals (Sweden)

    Kashan eAhmed

    2011-10-01

    Full Text Available In the recent past, deorphanization studies have described intermediates of energy metabolism to activate G protein-coupled receptors (GPCRs and to thereby regulate metabolic functions. GPR81, GPR109A and GPR109B, formerly known as the nicotinic acid receptor family, are encoded by clustered genes and share a high degree of sequence homology. Recently, hydroxy-carboxylic acids were identified as endogenous ligands of GPR81, GPR109A and GPR109B, and therefore these receptors have been placed into a novel receptor family of hydroxy-carboxylic acid (HCA receptors. The HCA1 receptor (GPR81 is activated by the glycolytic metabolite 2-hydroxy-propionic acid (lactate, the HCA2 receptor is activated by the ketone body 3-hydroxy-butyric acid and the HCA3 receptor (GPR109B is a receptor for the β-oxidation intermediate 3-hydroxy-octanoic acid. While HCA1 and HCA2 receptors are present in most mammalian species, the HCA3 receptor is exclusively found in humans and higher primates. HCA receptors are expressed in adipose tissue and mediate anti-lipolytic effects in adipocytes through Gi-type G-protein-dependent inhibition of adenylyl cyclase. HCA2 and HCA3 inhibit lipolysis during conditions of increased β-oxidation such as prolonged fasting, whereas HCA1 mediates the anti-lipolytic effects of insulin in the fed state. As HCA2 is a receptor for the established anti-dyslipidemic drug nicotinic acid, HCA1 and HCA3 also represent promising drug targets and several synthetic ligands for HCA receptors have been developed. In this article, we will summarize the deorphanization and pharmacological characterization of HCA receptors. Moreover, we will discuss recent progress in elucidating the physiological and pathophysiological role to further evaluate the therapeutic potential of the HCA receptor family for the treatment of metabolic disease.

  13. Role of leucine in isoprenoid metabolism. Incorporation of (3-/sup 13/C)leucine and of (2-/sup 3/H,4-/sup 14/C)-. beta. ,. beta. -dimethyl-acrylic acid into phytosterols by tissue cultures of Andrographis paniculata

    Energy Technology Data Exchange (ETDEWEB)

    Anastasis, P.; Freer, I.; Overton, K.; Rycroft, D.; Singh, S.B. (Glasgow Univ. (UK). Dept. of Chemistry)

    1985-02-01

    (3-/sup 13/C)Leucine is incorporated into phytosterols by tissue cultures of Andrographis paniculata by breakdown to acetyl-CoA and its subsequent incorporation via (3S)-3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) and mevalonic acid; (2-/sup 3/H,4-/sup 14/C)-..beta..,..beta..-dimethylacrylic acid also is not incorporated intact.

  14. Association of beta 2 -adrenergic receptor gene polymorphisms and nocturnal asthma in Saudi patients

    Directory of Open Access Journals (Sweden)

    Al-Rubaish Abdullah

    2011-01-01

    Full Text Available Background and Objectives : Two polymorphisms of beta 2 -adrenergic receptor (β2 -AR gene, namely the substitution from arginine (Arg to glycine (Gly at codon 16 and from glutamine (Gln to glutamic (Glu at codon 27, are linked with functional changes in the β2 -AR in the respiratory system even though they are not deemed to be susceptibility genes for asthma per se. The objective of this study was to investigate this association in a subset of asthmatic patients, namely those with nocturnal asthma. Methods : The β2 -AR gene polymorphisms at codon 16 and 27 were assessed in 40 patients clinically diagnosed with nocturnal asthma and 96 normal controls. Genomic DNA was obtained from whole blood and genotyping was carried out by a PCR based restriction fragment length polymorphism technique. Results : There was a statistically significant difference in genotype frequencies at codon 16 (Arg/Gly between nocturnal asthmatic patients and normal control subjects (P < 0.05. However, there was no statistically significant difference in allele frequencies between the two groups. In addition, there was a significant association between Arg16-Gly genotype with nocturnal asthma compared to homozygous Gly16 (codominant model P = 0.0033, OR = 3.69: 95% CI: 1.49-9.12. However, there were no statistically significant differences in genotype and allele frequencies at codon 27 (Gln/Glu between the normal control and nocturnal asthmatic groups (χ2 = 1.81, P = 0.41. The results also indicate that linkage disequilibrium existed between the β2 -AR codon 16 and β2 -AR codon 27 polymorphism (/ D΄/ = 0.577. The data for all haplotypes did not show a statistically significant association. Conclusion : We present the genotype and allele frequencies of β2 -AR gene polymorphisms in normal Saudi subjects and nocturnal asthmatic patients. There was a significant difference in genotype frequencies at codon 16 (Arg/Gly. However, our study indicates a poor association of

  15. Beta-aminobutyric acid priming of plant defense: the role of ABA and other hormones.

    Science.gov (United States)

    Baccelli, Ivan; Mauch-Mani, Brigitte

    2016-08-01

    Plants are exposed to recurring biotic and abiotic stresses that can, in extreme situations, lead to substantial yield losses. With the changing environment, the stress pressure is likely to increase and sustainable measures to alleviate the effect on our crops are sought. Priming plants for better stress resistance is one of the sustainable possibilities to reach this goal. Here, we report on the effects of beta-aminobutyric acid, a priming agent with an exceptionally wide range of action and describe its way of preparing plants to defend themselves against various attacks, among others through the modulation of their hormonal defense signaling, and highlight the special role of abscisic acid in this process. PMID:26584561

  16. Selective estrogen receptor-beta (SERM-beta) compounds modulate raphe nuclei tryptophan hydroxylase-1 (TPH-1) mRNA expression and cause antidepressant-like effects in the forced swim test.

    Science.gov (United States)

    Clark, J A; Alves, S; Gundlah, C; Rocha, B; Birzin, E T; Cai, S-J; Flick, R; Hayes, E; Ho, K; Warrier, S; Pai, L; Yudkovitz, J; Fleischer, R; Colwell, L; Li, S; Wilkinson, H; Schaeffer, J; Wilkening, R; Mattingly, E; Hammond, M; Rohrer, S P

    2012-11-01

    Estrogen acts through two molecularly distinct receptors termed estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ) which bind estradiol with similar affinities and mediate the effects of estrogen throughout the body. ERα plays a major role in reproductive physiology and behavior, and mediates classic estrogen signaling in such tissues as the uterus, mammary gland, and skeleton. ERβ, however, modulates estrogen signaling in the ovary, the immune system, prostate, gastrointestinal tract, and hypothalamus, and there is some evidence that ERβ can regulate ERα activity. Moreover, ERβ knockout studies and receptor distribution analyses in the CNS suggest that this receptor may play a role in the modulation of mood and cognition. In recent years several ERβ-specific compounds (selective estrogen receptor beta modulators; SERM-beta) have become available, and research suggests potential utility of these compounds in menopausal symptom relief, breast cancer prevention, diseases that have an inflammatory component, osteoporosis, cardiovascular disease, and inflammatory bowel disease, as well as modulation of mood, and anxiety. Here we demonstrate an antidepressant-like effect obtained using two SERM-beta compounds, SERM-beta1 and SERM-beta2. These compounds exhibit full agonist activity at ERβ in a cell based estrogen response element (ERE) transactivation assay. SERM-beta1 and 2 are non-proliferative with respect to breast as determined using the MCF-7 breast cancer cell-based assay and non-proliferative in the uterus as determined by assessing the effects of SERM-beta compounds on immature rat uterine weight and murine uterine weight. In vivo SERM-beta1 and 2 are brain penetrant and display dose dependent efficacy in the murine dorsal raphe assays for induction of tryptophan hydroxylase mRNA and progesterone receptor protein. These compounds show activity in the murine forced swim test and promote hippocampal neurogenesis acutely in rats. Taken

  17. Placental expression of estrogen receptor beta and its hormone binding variant – comparison with estrogen receptor alpha and a role for estrogen receptors in asymmetric division and differentiation of estrogen-dependent cells

    Directory of Open Access Journals (Sweden)

    Henley Donald C

    2003-04-01

    Full Text Available Abstract During human pregnancy, the production of 17-beta-estradiol (E2 rises steadily to eighty fold at term, and placenta has been found to specifically bind estrogens. We have recently demonstrated the expression of estrogen receptor alpha (ER-alpha protein in human placenta and its localization in villous cytotrophoblast (CT, vascular pericytes, and amniotic fibroblasts. In vitro, E2 stimulated development of large syncytiotrophoblast (ST aggregates. In the present study we utilized ER-beta affinity purified polyclonal (N19:sc6820 and ER-alpha monoclonal (clone h-151 antibodies. Western blot analysis revealed a single ~52 kDa ER-beta band in chorionic villi (CV protein extracts. In CV, strong cytoplasmic ER-beta immunoreactivity was confined to ST. Dual color immunohistochemistry revealed asymmetric segregation of ER-alpha in dividing villous CT cells. Prior to separation, the cell nuclei more distant from ST exhibited high ER-alpha, while cell nuclei associated with ST showed diminution of ER-alpha and appearance of ER-beta. In trophoblast cultures, development of ST aggregates was associated with diminution of ER-alpha and appearance of ER-beta immunoreactivity. ER-beta was also detected in endothelial cells, amniotic epithelial cells and fibroblasts, extravillous trophoblast (nuclear and cytoplasmic and decidual cells (cytoplasmic only. In addition, CFK-E12 (E12 and CWK-F12 (F12 monoclonal antibodies, which recognize ~64 kDa ER-beta with hormone binding domain, showed nuclear-specific reactivity with villous ST, extravillous trophoblast, and amniotic epithelium and fibroblasts. Western blot analysis indicated abundant expression of a ~64 kDa ER-beta variant in trophoblast cultures, significantly higher when compared to the chorionic villi and freshly isolated trophoblast cell protein extracts. This is the first report on ER-beta expression in human placenta and cultured trophoblast. Our data indicate that during trophoblast

  18. Synthesis and biological evaluation of potent {alpha}{sub v}{beta}{sub 3}-integrin receptor antagonists

    Energy Technology Data Exchange (ETDEWEB)

    Dijkgraaf, Ingrid [Department of Nuclear Medicine, Radboud University Nijmegen Medical Center, Nijmegen (Netherlands) and Department of Medicinal Chemistry, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht (Netherlands)]. E-mail: i.dijkgraaf@nucmed.umcn.nl; Kruijtzer, John A.W. [Department of Medicinal Chemistry, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht (Netherlands); Frielink, Cathelijne [Department of Nuclear Medicine, Radboud University Nijmegen Medical Center, Nijmegen (Netherlands); Soede, Annemieke C. [Department of Nuclear Medicine, Radboud University Nijmegen Medical Center, Nijmegen (Netherlands); Hilbers, Hans W. [Department of Medicinal Chemistry, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht (Netherlands); Oyen, Wim J.G. [Department of Nuclear Medicine, Radboud University Nijmegen Medical Center, Nijmegen (Netherlands); Corstens, Frans H.M. [Department of Nuclear Medicine, Radboud University Nijmegen Medical Center, Nijmegen (Netherlands); Liskamp, Rob M.J. [Department of Medicinal Chemistry, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht (Netherlands); Boerman, Otto C. [Department of Nuclear Medicine, Radboud University Nijmegen Medical Center, Nijmegen (Netherlands)

    2006-11-15

    Introduction: {alpha}{sub v}{beta}{sub 3} Integrin is expressed in sprouting endothelial cells in growing tumors, whereas it is absent in quiescent blood vessels. In addition, various tumor cell types express {alpha}{sub v}{beta}{sub 3} integrin. {alpha}{sub v}{beta}{sub 3} Integrin, a transmembrane heterodimeric protein, binds to the arginine-glycine-aspartic acid (RGD) amino acid sequence of extracellular matrix proteins such as vitronectin and plays a pivotal role in invasion, proliferation and metastasis. Due to the selective expression of {alpha}{sub v}{beta}{sub 3} integrin in tumors, radiolabeled RGD peptides and peptidomimetics are attractive candidates for tumor targeting. Methods: A cyclic RGD peptide, a peptoid-peptide hybrid, an all-peptoid and a peptidomimetic compound were synthesized, conjugated with 1,4,7,10-tetraazadodecane-N,N',N'',N'''-tetraacetic acid (DOTA) and radiolabeled with {sup 111}In. Their in vitro and in vivo {alpha}{sub v}{beta}{sub 3}-binding characteristics were determined. Results: IC{sub 5} values were 236 nM for DOTA-E-c(RGDfK), 219 nM for DOTA-peptidomimetic, >10 mM for DOTA-all-peptoid and 9.25 mM for the peptoid-peptide hybrid DOTA-E-c(nRGDfK). {sup 111}In-labeled compounds, except for [{sup 111}In]DOTA-all-peptoid, showed specific uptake in human {alpha}{sub v}{beta}{sub 3}-expressing tumors xenografted in athymic mice. Tumor uptake for [{sup 111}In]DOTA-E-c(RGDfK) was 1.73{+-}0.4% ID/g (2 h postinjection) and that of [{sup 111}In]DOTA-peptidomimetic was 2.04{+-}0.3% ID/g. Tumor uptake for the peptoid-peptide hybrid [{sup 111}In]DOTA-E-c(nRGDfK) was markedly lower (0.45{+-}0.07% ID/g). The all-peptoid [{sup 111}In]DOTA-E-c(nRGnDnFnK) did not show specific uptake in tumors (0.11{+-}0.04% ID/g). Conclusions: The peptidomimetic compound and the cyclic RGD peptide have a high affinity for {alpha}{sub v}{beta}{sub 3} integrin, and these compounds have better tumor-targeting characteristics than the

  19. Biological activity of all-trans retinol requires metabolic conversion to all-trans retinoic acid and is mediated through activation of nuclear retinoid receptors in human keratinocytes.

    Science.gov (United States)

    Kurlandsky, S B; Xiao, J H; Duell, E A; Voorhees, J J; Fisher, G J

    1994-12-30

    The biological activity of all-trans retinol, in human keratinocytes, was investigated through metabolic and functional analyses that assessed the capacity for retinol uptake and metabolism and the mechanism of retinol-induced activation of gene transcription. Human keratinocytes converted all-trans retinol predominantly to retinyl esters, which accounted for 60 and 90% of cell-associated radiolabel after a 90-min pulse and a 48-h chase, respectively. Human keratinocytes also metabolized all-trans retinol to low levels of all-trans retinoic acid (11.47-131.3 ng/mg of protein) in a dose-dependent manner, between 0.3 and 10 microM added retinol. Small amounts of 13-cis retinoic acid (5.47-8.62 ng/mg of protein) were detected, but 9-cis retinoic acid was detected only when keratinocytes were incubated with radiolabeled retinol. There was no accumulation of the oxidized catabolic metabolites 4-hydroxy- or 4-oxoretinoic acid; however, 5,6-epoxy retinoic acid was detected at pharmacological levels (10 and 30 microM) of added retinol. Biological activity of retinol was assessed through analysis of two known retinoic acid-mediated responses: 1) reduction of type I epidermal transglutaminase and 2) activation of a retinoic acid receptor-dependent reporter gene, beta RARE3-tk-CAT. Both all-trans retinol and all-trans retinoic acid reduced type I epidermal transglutaminase in a dose-dependent manner; however, the ED50 for all-trans retinol (10 nM) was 10 times greater than for all-trans retinoic acid (1 nM). All-trans retinol also stimulated beta RARE3-tk-CAT reporter gene activity in a dose-dependent manner. Half-maximal induction was observed at 30 nM retinol, which was again 10-fold greater than observed with all-trans retinoic acid. Cotransfection of human keratinocytes with expression vectors for dominant negative mutant retinoic acid and retinoid X receptors reduced retinol-induced beta RARE3-tk-CAT reporter gene activation by 80%. Inhibition of conversion of all

  20. Synthesis and structure-activity studies on acidic amino acids and related diacids as NMDA receptor ligands

    DEFF Research Database (Denmark)

    Johansen, T N; Frydenvang, Karla Andrea; Ebert, B;

    1994-01-01

    The 3-isoxazolol amino acids (S)-2-amino-3-(3-hydroxy-5-methyl-4- isoxazolyl)propionic acid [(S)-AMPA, 2] and (R,S)-2-amino-2-(3-hydroxy-5-methyl-4-isoxazolyl)acetic acid (AMAA, 5a) (Figure 1) are potent and specific agonists at the AMPA and N-methyl-D-aspartic acid (NMDA) subtypes, respectively......, of (S)-glutamic acid (1) receptors. A number of amino acids and diacids structurally related to AMAA were synthesized and tested electrophysiologically and in receptor-binding assays. The hydroxymethyl analogue 7c of AMAA was an NMDA agonist approximately equipotent with AMAA in the [3H...

  1. Effect of clavulanic acid on the activities of ten beta-lactam agents against members of the Bacteroides fragilis group.

    Science.gov (United States)

    Lamothe, F; Auger, F; Lacroix, J M

    1984-01-01

    Clavulanic acid reduced the MICs of amoxicillin, carbencillin , cefamandole, cefotaxime, ceftazidime, ceftizoxime, cephalothin, and penicillin G, but not of cefoxitin or moxalactam, against 77 isolates of the Bacteroides fragilis group, all rapidly beta-lactamase positive by the nitrocefin slide test. It had no effect on the susceptibilities of eight Bacteroides distasonis strains that were slowly beta-lactamase positive (18 h of incubation). PMID:6732233

  2. Polymorphism analysis in estrogen receptors alpha and beta genes and their association with infertile population in Pakistan

    OpenAIRE

    Liaqat, Sinha; Hasnain, Shahida; Muzammil, Saima; Hayat, Sumreen

    2015-01-01

    Studies on polymorphism of estrogen receptor (ESR) alpha and beta genes have been mostly implicated in infertility, but the results have been controversial due to lack of comprehensive data. The present study focused on association of ESR genes with both male and female infertility. In ESRα, PvuII (rs2234693) and XbaI (rs9340799) were studied while in ESRβ gene, risk of infertility was determined for silent G/A RsaI (rs1256049) polymorphism. Total 124 subjects (74 cases and 50 controls) were ...

  3. Effect of Cardiopulmonary Bypass on Beta Adrenergic ReceptorAdenylate Cyclase System on Surfaces of Peripheral Lymphocytes

    Institute of Scientific and Technical Information of China (English)

    LUO Ailin; TIAN Yuke; JIN Shiao

    2000-01-01

    The experimental results showed that the level of CAMP, the ratio of cAPM to cGMP,IL-2R expression and IL-2 production in vitro in lymphocytes immediate and 2 weeks after cardiopulmonary bypass (CPB) were significantly lower than those before anesthetics in the patients undergoing cardiac surgery with CPB. These findings suggested that CPB could cause serious damage to adrenergic beta receptor-adenylate cyclase system on circulating lymphocytes surfaces,which might be one of the mechanisms resulting in immunosuppression after open heart surgery with CPB.

  4. FATTY ACIDS MODULATE TOLL-LIKE RECEPTOR 4 ACTIVATION THROUGH REGULATION OF RECEPTOR DIMERIZATION AND RECRUITMENT INTO LIPID RAFTS

    Science.gov (United States)

    The saturated fatty acids acylated on Lipid A of lipopolysaccharide (LPS) or bacterial lipoproteins play critical roles in ligand recognition and receptor activation for Toll-like Receptor 4 (TLR4) and TLR2. The results from our previous studies (J Biol Chem 2003, 2004) demonstrated that saturated ...

  5. Estrogen receptors alpha and beta in rat placenta: detection by RT-PCR, real time PCR and Western blotting

    Directory of Open Access Journals (Sweden)

    Al-Bader Maie D

    2006-03-01

    Full Text Available Abstract Background High levels of estrogens during pregnancy not only retard placental and fetal growth but can lead to reproductive tract abnormalities in male progeny. Estrogens act through estrogen receptors (ER to modulate the transcription of target genes. These ER exist in two isoforms, ER alpha and ER beta and recently several variants of these isoforms have been identified. Methods The expressions of ER isoforms and variants have been studied in rat placenta at 16, 19 and 21 days gestation (dg. Gene expression was assessed using RT-PCR and real time PCR while protein expression was studied using Western blotting followed by immunodetection. Placental homogenates were probed with: a monoclonal antibody raised against the steroid binding domain of the ER alpha (ER alpha -S, a monoclonal antibody raised against the hinge region of ER alpha (ER alpha -H and a polyclonal antibody raised against the amino terminus of ER beta. Results ER alpha and ER beta mRNA and protein were detected from as early as 16 dg. Two PCR products were detected for ER alpha, one for the wild type ER alpha, and a smaller variant. Real time PCR results suggested the presence of a single product for ER beta. The antibodies used for detection of ER alpha protein both identified a single 67 kDa isoform; however a second 54 kDa band, which may be an ER alpha variant, was identified when using the ER alpha -H antibody. The abundance of both ER alpha bands decreased significantly between 16 and 19 dg. As for ER beta, four bands (76, 59, 54 and 41 kDa were detected. The abundance of the 59 and 54 kDa bands decreased significantly between 16 and 19 dg. Conclusion This study shows that both ER protein isoforms and their variants are present in rat placenta. The decrease in their expression near parturition suggests that the placenta may be relatively unresponsive to estrogens at this stage.

  6. Validation study of a receptor-based lateral flow assay for detection of beta-lactam antibiotics in milk.

    Science.gov (United States)

    Abouzied, Mohamed; Sarzynski, Michael; Walsh, Aaron; Wood, Heather; Mozola, Mark

    2009-01-01

    A validation study designed to meet the requirements of the AOAC Research Institute and the U.S. Food and Drug Administration (FDA), Center for Veterinary Medicine, was conducted for a receptor-based, immunochromatographic method (BetaStar US) for detection of beta-lactam antibiotic residues in raw, commingled bovine milk. The assay was found to detect amoxicillin, ampicillin, cephapirin, cloxacillin, and penicillin G at levels below the FDA tolerance/safe levels but above the maximum sensitivity thresholds established by the National Conference on Interstate Milk Shipments. Results of the Part I (internal) and Part II (independent laboratory) dose-response studies using spiked samples were in very close agreement for all five drugs tested, with differences between the Part I and Part II 90/95% sensitivity values ranging from 0 to 1 ppb. The test was able to detect all five drugs at the approximate 90/95% sensitivity levels when present as incurred residues in milk collected from cows that had been treated with the specific drug. A sixth drug, ceftiofur, was found to be undetectable at levels of 1000 control milk samples. The assay was found to be applicable to the testing of frozen raw milk samples. Results of ruggedness experiments established the operating parameter tolerances for the BetaStar US assay. Results of cross-reactivity testing established that the assay detects certain other beta-lactam drugs (dicloxacillin and ticarcillin), but it does not cross-react with any of 30 drugs belonging to other classes. Abnormally high bacterial or somatic cell counts in raw milk produced no interference with the ability of the test to detect beta-lactams at tolerance/safe levels. PMID:19610391

  7. Molecular Characterization and Sex-Specific Tissue Expression of Estrogen Receptor Alpha (esr1), Estrogen Receptor Beta-a (esr2a) and Ovarian Aromatase (cyp19a1a) in Yellow Perch (Perca flavescens)

    Science.gov (United States)

    Yellow perch (Perca flavescens) exhibit an estrogen-stimulated sexual size dimorphism (SSD) wherein females grow faster and larger than males. To aid in the examination of this phenomenon, the cDNA sequences encoding estrogen receptor-alpha (esr1), estrogen receptor-beta-a (esr2a) and ovarian aroma...

  8. 17-Beta-estradiol inhibits transforming growth factor-beta signaling and function in breast cancer cells via activation of extracellular signal-regulated kinase through the G protein-coupled receptor 30.

    Science.gov (United States)

    Kleuser, Burkhard; Malek, Daniela; Gust, Ronald; Pertz, Heinz H; Potteck, Henrik

    2008-12-01

    Breast cancer development and breast cancer progression involves the deregulation of growth factors leading to uncontrolled cellular proliferation, invasion and metastasis. Transforming growth factor (TGF)-beta plays a crucial role in breast cancer because it has the potential to act as either a tumor suppressor or a pro-oncogenic chemokine. A cross-communication between the TGF-beta signaling network and estrogens has been postulated, which is important for breast tumorigenesis. Here, we provide evidence that inhibition of TGF-beta signaling is associated with a rapid estrogen-dependent nongenomic action. Moreover, we were able to demonstrate that estrogens disrupt the TGF-beta signaling network as well as TGF-beta functions in breast cancer cells via the G protein-coupled receptor 30 (GPR30). Silencing of GPR30 in MCF-7 cells completely reduced the ability of 17-beta-estradiol (E2) to inhibit the TGF-beta pathway. Likewise, in GPR30-deficient MDA-MB-231 breast cancer cells, E2 achieved the ability to suppress TGF-beta signaling only after transfection with GPR30-encoding plasmids. It is most interesting that the antiestrogen fulvestrant (ICI 182,780), which possesses agonistic activity at the GPR30, also diminished TGF-beta signaling. Further experiments attempted to characterize the molecular mechanism by which activated GPR30 inhibits the TGF-beta pathway. Our results indicate that GPR30 induces the stimulation of the mitogen-activated protein kinases (MAPKs), which interferes with the activation of Smad proteins. Inhibition of MAPK activity prevented the ability of E2 from suppressing TGF-beta signaling. These findings are of great clinical relevance, because down-regulation of TGF-beta signaling is associated with the development of breast cancer resistance in response to antiestrogens.

  9. 8-[2-(2-pentyl-cyclopropylmethyl)-cyclopropyl]-octanoic acid stimulates GABA release from interneurons projecting to CA1 pyramidal neurons in the rat hippocampus via pre-synaptic alpha7 acetylcholine receptors.

    Science.gov (United States)

    Kanno, Takeshi; Yaguchi, Takahiro; Yamamoto, Satoshi; Yamamoto, Hideyuki; Fujikawa, Hirokazu; Nagata, Tetsu; Tanaka, Akito; Nishizaki, Tomoyuki

    2005-11-01

    Nicotinic acetylcholine (ACh) receptors, such as alpha7, alpha3beta4 and alpha4beta2 receptors in the hippocampus, are suggested to modulate neurotransmitter release. 8-[2-(2-Pentyl-cyclopropylmethyl)-cyclopropyl]-octanoic acid (DCP-LA) (100 nM), a linoleic acid derivative, potentiated responses of alpha7, alpha3beta4 and alpha4beta2 ACh receptors expressed in Xenopus oocytes that are blocked by 3-(1-[dimethylaminopropyl] indol-3-yl)-4-[indol-3-yl] maleimide (GF109203X), a selective inhibitor of protein kinase C (PKC), except for alpha3beta4 ACh receptors. DCP-LA enhanced the nicotine-triggered release of GABA from rat hippocampal slices in the presence of tetrodotoxin in a bell-shaped dose-dependent manner at concentrations ranging from 10 nM to 10 microM, although DCP-LA by itself had no effect on GABA release. The DCP-LA action was inhibited by GF109203X or alpha-bungarotoxin, an inhibitor of alpha7 ACh receptors, but not by mecamylamine or dihydro-beta-erithroidine, an inhibitor of alpha3beta4 and alpha4beta2 ACh receptors. A similar effect on GABA release was obtained with 12-O-tetradecanoylphorbol 13-acetate, a PKC activator. DCP-LA (100 nM) also enhanced GABA release triggered by choline, an agonist of alpha7 ACh receptors, but not 3-[2(s)-azetidinylmethoxy] pyridine, an agonist of alpha4beta2 ACh receptors. In addition, DCP-LA (100 nM) increased the rate of nicotine-triggered GABA(A) receptor-mediated miniature inhibitory post-synaptic currents, monitored from CA1 pyramidal neurons of rat hippocampal slices, and the effect was also inhibited by GF109203X or alpha-bungarotoxin but not by mecamylamine. Thus, the results of the present study indicate that DCP-LA stimulates GABA release by enhancing activity of pre-synaptic alpha7 ACh receptors present on the GABAergic terminals of interneurons that transmit to CA1 pyramidal neurons via a PKC pathway. PMID:16248884

  10. cDNA-derived amino-acid sequence of a land turtle (Geochelone carbonaria) beta-chain hemoglobin.

    Science.gov (United States)

    Bordin, S; Meza, A N; Saad, S T; Ogo, S H; Costa, F F

    1997-06-01

    The cDNA sequence encoding the turtle Geochelone carbonaria beta-chain was determinated. The isolation of hemoglobin mRNA was based on degenerate primers' PCR in combination with 5'- and 3'-RACE protocol. The full length cDNA is 615 bp with the ATG start codon at position 53 and TGA stop codon at position 495; The AATAAA polyadenylation signal is found at position 599. The deduced polypeptyde contains 146 amino-acid residues. The predicted amino acid sequence shares 83% identity with the beta-globin of a related specie, the aquatic turtle C. p. belli. Otherwise, identity is higher when compared with chicken beta-Hb (80%) than with other reptilian orders (Squamata, 69%, and Crocodilia, 61%). Compared with human HbA, there is 67% identity, and at least three amino acid substitutions could be of some functional significance (Glu43 beta-->Ser, His116 beta-->Thr and His143 beta-->Leu). To our knowledge this represents the first cDNA sequence of a reptile globin gene described. PMID:9238523

  11. Chromosomal translocation involving the beta T cell receptor gene in acute leukemia

    OpenAIRE

    1988-01-01

    DNA spanning a t(7;19) chromosomal translocation breakpoint was isolated from the human T cell line SUP-T7 established from an acute lymphoblastic leukemia. Nucleotide sequence analysis showed that the point of crossover on chromosome 7 occurred immediately adjacent to joining segment J beta 1.1 within the TCR-beta gene, suggesting that this translocation resulted from an error in TCR gene rearrangement. On chromosome 19, the translocation occurred within a previously uncharacterized transcri...

  12. The structure, rearrangement, and ontogenic expression of DB and JB gene segments of the Mexican axolotl T-cell antigen receptor beta chain (TCRB).

    Science.gov (United States)

    Kerfourn, F; Charlemagne, J; Fellah, J S

    1996-01-01

    We sequenced a total of 189 independent rearrangements in which the VB7.1 element is associated with CB1 (99 clones) or CB2 (90 clones) isotypes of the T-cell receptor (TCR) beta chain in the Mexican axolotl. Three stages of development were analyzed: 2.5 months, 10 months, and 25 months. Three JB1 segments were associated with the VB-CB1 rearrangements and six JB2 segments with VB-CB2. As in other vertebrates, some amino acid positions were conserved in all Jbetas (e. g., Phe-108, Gly-109, Gly-111, Thr-112, and Val-116). Two 11 nucleotides DB-like sequences, differed by one (A or T) central residue and could be productively read in the three putative reading frames. Most of the DB1 and JB1 segments were in the VB-CB1 clones, and most of the DB2 and JB2 segments were in the VB-CB2 clones, suggesting that the TCRB locus is organized into independent DB-JB-CB clusters that used the same collection of VB segments. About 40% of the beta-chain VDJ junctions in 2.5-month-old larvae had N nucleotides, compared with about 73% in 10 - 25-month old animals. The beta-chain VDJ junctions had about 30% of defective rearrangements at all stages of development, which could be due to the slow rate of cell division in the axolotl lymphoid organs, and the large genome in this urodele. Many of the axolotl CDRbeta3 sequences deduced for in frame VDJ rearrangements are the same in animals of different origins. Such redundancy could be a statistical effect due to the small number of thymocytes in the developing axolotl, rather than to some bias due to junctional preferences.

  13. The structure, rearrangement, and ontogenic expression of DB and JB gene segments of the Mexican axolotl T-cell antigen receptor beta chain (TCRB).

    Science.gov (United States)

    Kerfourn, F; Charlemagne, J; Fellah, J S

    1996-01-01

    We sequenced a total of 189 independent rearrangements in which the VB7.1 element is associated with CB1 (99 clones) or CB2 (90 clones) isotypes of the T-cell receptor (TCR) beta chain in the Mexican axolotl. Three stages of development were analyzed: 2.5 months, 10 months, and 25 months. Three JB1 segments were associated with the VB-CB1 rearrangements and six JB2 segments with VB-CB2. As in other vertebrates, some amino acid positions were conserved in all Jbetas (e. g., Phe-108, Gly-109, Gly-111, Thr-112, and Val-116). Two 11 nucleotides DB-like sequences, differed by one (A or T) central residue and could be productively read in the three putative reading frames. Most of the DB1 and JB1 segments were in the VB-CB1 clones, and most of the DB2 and JB2 segments were in the VB-CB2 clones, suggesting that the TCRB locus is organized into independent DB-JB-CB clusters that used the same collection of VB segments. About 40% of the beta-chain VDJ junctions in 2.5-month-old larvae had N nucleotides, compared with about 73% in 10 - 25-month old animals. The beta-chain VDJ junctions had about 30% of defective rearrangements at all stages of development, which could be due to the slow rate of cell division in the axolotl lymphoid organs, and the large genome in this urodele. Many of the axolotl CDRbeta3 sequences deduced for in frame VDJ rearrangements are the same in animals of different origins. Such redundancy could be a statistical effect due to the small number of thymocytes in the developing axolotl, rather than to some bias due to junctional preferences. PMID:8753858

  14. Structure of the T-cell receptor in a Ti alpha beta, Ti gamma delta double positive T-cell line

    DEFF Research Database (Denmark)

    Kuhlmann, J; Geisler, C

    1993-01-01

    is still not known. It has been suggested that each T-cell receptor contains two Ti dimers. To gain insight into the structure of the T-cell receptor we constructed a Ti alpha beta, Ti gamma delta double positive T-cell line which contained four functional Ti chains (Ti alpha, beta, gamma, and delta......The multichain T-cell receptor is composed of at least six different polypeptide chains. The clonotypic Ti heterodimer (Ti alpha beta or Ti gamma delta) is non-covalently associated with the CD3 chains (CD3 gamma delta epsilon zeta). The exact number of subunits constituting the T-cell receptor......). The data demonstrated an absence of Ti dimers containing mixtures of chains other than the typical Ti alpha beta and Ti gamma delta combinations. Furthermore, by co-modulation experiments we demonstrated that the Ti alpha beta and the Ti gamma delta dimers were not expressed in the same T-cell receptor...

  15. Effect of clavulanic acid on susceptibility of Campylobacter jejuni and Campylobacter coli to eight beta-lactam antibiotics.

    Science.gov (United States)

    Gaudreau, C L; Lariviere, L A; Lauzer, J C; Turgeon, F F

    1987-01-01

    The effect of clavulanic acid on the susceptibility of 32 strains of Campylobacter jejuni and Campylobacter coli to eight beta-lactam agents was studied. Almost all strains tested became susceptible to amoxicillin and ticarcillin with 1 microgram of clavulanic acid per ml. This compound had little or no effect on susceptibility to penicillin G, cephalothin, cefamandole, and cefoxitin. Clavulanic acid had a marginal effect on cefotaxime and moxalactam susceptibility. PMID:3619428

  16. Effect of clavulanic acid on susceptibility of Campylobacter jejuni and Campylobacter coli to eight beta-lactam antibiotics.

    OpenAIRE

    Gaudreau, C L; Lariviere, L A; Lauzer, J C; Turgeon, F F

    1987-01-01

    The effect of clavulanic acid on the susceptibility of 32 strains of Campylobacter jejuni and Campylobacter coli to eight beta-lactam agents was studied. Almost all strains tested became susceptible to amoxicillin and ticarcillin with 1 microgram of clavulanic acid per ml. This compound had little or no effect on susceptibility to penicillin G, cephalothin, cefamandole, and cefoxitin. Clavulanic acid had a marginal effect on cefotaxime and moxalactam susceptibility.

  17. The low-density lipoprotein receptor-related protein 10 is a negative regulator of the canonical Wnt/{beta}-catenin signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Young-Hee; Sekiya, Manami; Hirata, Michiko; Ye, Mingjuan; Yamagishi, Azumi [Department of Molecular and Biochemical Nutrition, Graduate School of Human Life Science, Osaka City University, Osaka 558-8585 (Japan); Lee, Sang-Mi; Kang, Man-Jong [Department of Animal Science, College of Agriculture and Life Science, Chonnam National University, Gwangju 500-757 (Korea, Republic of); Hosoda, Akemi; Fukumura, Tomoe; Kim, Dong-Ho [Department of Molecular and Biochemical Nutrition, Graduate School of Human Life Science, Osaka City University, Osaka 558-8585 (Japan); Saeki, Shigeru, E-mail: saeki@life.osaka-cu.ac.jp [Department of Molecular and Biochemical Nutrition, Graduate School of Human Life Science, Osaka City University, Osaka 558-8585 (Japan)

    2010-02-19

    Wnt signaling pathways play fundamental roles in the differentiation, proliferation and functions of many cells as well as developmental, growth, and homeostatic processes in animals. Low-density lipoprotein receptor (LDLR)-related protein (LRP) 5 and LRP6 serve as coreceptors of Wnt proteins together with Frizzled receptors, triggering activation of canonical Wnt/{beta}-catenin signaling. Here, we found that LRP10, a new member of the LDLR gene family, inhibits the canonical Wnt/{beta}-catenin signaling pathway. The {beta}-catenin/T cell factor (TCF) transcriptional activity in HEK293 cells was activated by transfection with Wnt3a or LRP6, which was then inhibited by co-transfection with LRP10. Deletion of the extracellular domain of LRP10 negated its inhibitory effect. The inhibitory effect of LRP10 was consistently conserved in HEK293 cells even when GSK3{beta} phosphorylation was inhibited by incubation with lithium chloride and co-transfection with constitutively active S33Y-mutated {beta}-catenin. Nuclear {beta}-catenin accumulation was unaffected by LRP10. The present studies suggest that LRP10 may interfere with the formation of the {beta}-catenin/TCF complex and/or its binding to target DNA in the nucleus, and that the extracellular domain of LRP10 is critical for inhibition of the canonical Wnt/{beta}-catenin signaling pathway.

  18. Quantification of syntrophic fatty acid-beta-oxidizing bacteria in a mesophilic biogas reactor by oligonucleotide probe hybridization

    DEFF Research Database (Denmark)

    Hansen, K.W.; Ahring, Birgitte Kiær; Raskin, L.

    1999-01-01

    Small-subunit rRNA sequences were obtained for two saturated fatty acid-beta-oxidizing syntrophic bacteria, Syntrophomonas sapovorans and Syntrophomonas wolfei LYE, and sequence analysis confirmed their classification as members of the family Syntrophomonadaceae. S, wolfei LYE was closely related...... to S. wolfei subsp. wolfei, but S. sapovorans did not cluster with the other members of the genus Syntrophomonas, Five oligonucleotide probes targeting the small-subunit rRNA of different groups within the family Syntrophomonadaceae, which contains all currently known saturated fatty acid-beta-oxidizing...... fatty acid-beta-oxidizing syntrophic bacteria in methanogenic environments, the microbial community structure of a sample from a full-scale biogas plant was determined. Hybridization results with probes for syntrophic bacteria-and methanogens were compared to specific methanogenic activities...

  19. Obeticholic acid, a synthetic bile acid agonist of the farnesoid X receptor, attenuates experimental autoimmune encephalomyelitis.

    Science.gov (United States)

    Ho, Peggy P; Steinman, Lawrence

    2016-02-01

    Bile acids are ligands for the nuclear hormone receptor, farnesoid X receptor (FXR). The bile acid-FXR interaction regulates bile acid synthesis, transport, and cholesterol metabolism. Recently, bile acid-FXR regulation has been reported to play an integral role in both hepatic and intestinal inflammation, and in atherosclerosis. In this study, we found that FXR knockout mice had more disease severity in experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). Obeticholic acid (6α-ethyl-chenodeoxycholic acid, 6-ECDCA), a synthetic FXR agonist, is an orally available drug that is currently in clinical trials for the treatment of inflammatory diseases such as alcoholic hepatitis, nonalcoholic steatohepatitis, and primary biliary cirrhosis. When we treated mice exhibiting established EAE with 6-ECDCA, or the natural FXR ligand chenodeoxycholic acid (CDCA), clinical disease was ameliorated by (i) suppressing lymphocyte activation and proinflammatory cytokine production; (ii) reducing CD4(+) T cells and CD19(+) B cell populations and their expression of negative checkpoint regulators programmed cell death protein 1 (PD1), programmed death-ligand 1 (PD-L1), and B and T lymphocyte attenuator (BTLA); (iii) increasing CD8(+) T cells and PD1, PDl-1, and BTLA expression; and (iv) reducing VLA-4 expression in both the T- and B-cell populations. Moreover, adoptive transfer of 6-ECDCA- or CDCA-treated donor cells failed to transfer disease in naive recipients. Thus, we show that FXR functions as a negative regulator in neuroinflammation and we highlight that FXR agonists represent a potential previously unidentified therapy for MS. PMID:26811456

  20. Acquired resistance of Nocardia brasiliensis to clavulanic acid related to a change in beta-lactamase following therapy with amoxicillin-clavulanic acid.

    Science.gov (United States)

    Steingrube, V A; Wallace, R J; Brown, B A; Pang, Y; Zeluff, B; Steele, L C; Zhang, Y

    1991-01-01

    Previous studies have demonstrated that Nocardia brasiliensis is susceptible to amoxicillin-clavulanic acid and that its beta-lactamases are inhibited in vitro by clavulanic acid. A cardiac transplant patient with disseminated infection caused by N. brasiliensis was treated with this drug combination with good response, but relapsed while still on therapy. The relapse isolate was found to be identical to the initial isolate by using genomic DNA restriction fragment patterns obtained by pulsed field gel electrophoresis, but it was resistant to amoxicillin-clavulanic acid. On isoelectric focusing, the beta-lactamase from the relapse isolate exhibited a shift in the isoelectric point (pI) of its major band from 5.10 to 5.04 compared with the enzyme from the pretreatment isolate. As determined by using values of the amount of beta-lactamase inhibitor necessary to give 50 +/- 5% inhibition of beta-lactamase-mediated hydrolysis of 50 microM nitrocefin, the beta-lactamase of the relapse isolate was also 200-fold more resistant than the enzyme from the pretreatment isolate to clavulanic acid and was more resistant to sulbactam, tazobactam, cloxacillin, and imipenem. The beta-lactamase of the relapse isolate exhibited a 10-fold decrease in hydrolytic activity for cephaloridine and other hydrolyzable cephalosporins compared with that for nitrocefin. Acquired resistance to amoxicillin-clavulanic acid in this isolate of N. brasiliensis appears to have resulted from a mutational change affecting the inhibitor and active site(s) in the beta-lactamase. Images PMID:2039203

  1. HLA-DR, DQ and T cell antigen receptor constant beta genes in Japanese patients with ulcerative colitis.

    Science.gov (United States)

    Kobayashi, K; Atoh, M; Konoeda, Y; Yagita, A; Inoko, H; Sekiguchi, S

    1990-01-01

    We studied the T cell antigen receptor (TcR) constant beta chain genes on HLA typed Japanese patients with ulcerative colitis (UC). A TcR constant beta EcoRI 6.0-kb fragment was present in all Japanese UC patients (n = 17) but completely absent in the controls (n = 35) (chi2 = 47.6, P less than 0.001). The frequency of HLA-DR2 antigen was significantly higher in UC patients (85% versus 28% in controls, P less than 0.001). Furthermore, HLA-DQw1 antigen was also increased in UC patients (96% versus 60% in controls, P less than 0.001). However, HLA-DR4 antigen was significantly decreased in UC patients (12% versus 37%, P = 0.02). HLA-DR1 antigen was not found in UC patients and was present in only 15% of the controls. These results suggest that TcR beta chain and HLA-DQw1 antigen may be important in the pathogenesis of Japanese UC. Images Fig. 1 PMID:1973647

  2. Expression of estrogen receptors alpha and beta in the corpus luteum and uterus from non-pregnant and pregnant llamas.

    Science.gov (United States)

    Powell, Susan A; Smith, Bradford B; Timm, Karen I; Menino, Alfred R

    2007-08-01

    Because estrogen may be involved in maternal recognition of pregnancy and embryonic migration in llamas, expression of estrogen receptor subtypes alpha (ERalpha) and beta (ERbeta) was evaluated in corpus luteum (CL), endometrium, and uterus using relative RT-PCR. Tissues were recovered from sterile-mated (SM) and pregnant (PG) females during Days 7-11 and 7-13 (Day 0 = day of mating), respectively, and follicular phase and juvenile females. Luteal expression of ERalpha and beta was similar (P > 0.10) in SM and PG females and within Days 7-11, however, expression of ERalpha in ovarian tissue from follicular phase females was greater (P Uterus expressed less ERalpha and beta compared to endometrium (P = 0.07 and P 0.10) between SM and PG females or by day. The presence of luteal ER during this period may mean a role for estradiol in maternal recognition of pregnancy. Observed increases in uterine ER expression with no changes in endometrium suggest expression increased in myometrium and/or perimetrium. Upregulation of myometrial ERbeta in PG females may be involved in supporting uterine migration of the embryo. PMID:17219432

  3. Pet measurements of postsynaptic muscarinic and beta adrenergic receptors in the heart

    International Nuclear Information System (INIS)

    There is ample evidence from both experimental and clinical studies that changes in β-adrenergic and muscarinic receptor density can be associated with such cardiac diseases as congestive heart failure, myocardial ischemia and infarction, cardiomyopathy, diabetes, or thyroid-induced muscle disease. Changes in B-adrenergic density also have been shown in the denervated transplanted heart. These alterations of cardiac receptors have been demonstrated in vitro on homogenates from samples collected mainly during surgery or post mortem. Recent developments of Positron Emission Tomography (PET) techniques and of radioligands suitable for cardiac receptor binding studies in vivo have made possible both the imaging and the measurement of receptor density. From these studies, important information is now available concerning physiologic and pathologic conditions, as well as alterations induced by treatment. For the investigation of myocardial B-adrenergic receptors we have used [11C] CGP 12177, a potent hydrophilic antagonist of the 3-adrenergic receptor. The quantification of myocardial muscarinic receptors in vivo has been obtained with [11C] MQNB, a nonmetabolized hydrophilic antagonist of the muscarinic receptor. Receptor density and affinity have been measured by a kinetic, nonequilibrium approach in an experimental protocol that provides sufficient data to determine values for all parameters from a single experiment

  4. Pavlovian conditioning of morphine-induced alterations of immune status: evidence for peripheral beta-adrenergic receptor involvement.

    Science.gov (United States)

    Coussons-Read, M E; Dykstra, L A; Lysle, D T

    1994-09-01

    The present studies examined the involvement of peripheral beta-adrenergic receptor activity in the establishment and expression of conditioned morphine-induced alterations of immune status. Previous work in our laboratory has shown that morphine's immunomodulatory effects can become conditioned to environmental stimuli which predict drug administration. These immune alterations include conditioned changes in natural killer cell activity, interleukin-2 production, and mitogen-induced lymphocyte proliferation. During the training phase of these experiments, Lewis rats received two conditioning sessions during which a subcutaneous injection of 15 mg/kg morphine sulfate was paired with exposure to a distinctive environment. On the test day, rats were reexposed to the conditioned stimulus prior to sacrifice. Saline or nadolol (0.002, 0.02, 0.2, or 2.0 mg/kg) was administered either prior to the training sessions or prior to the test session. Administration of nadolol prior to training did not affect the development of conditioned alterations of immune status. Conversely, nadolol administration prior to testing completely attenuated the expression of a subset of the conditioned morphine-induced changes in immune status. Taken together, these studies suggest that whereas peripheral beta-adrenergic receptor activity is not required for the establishment of conditioned morphine-induced alterations of immune status, it is involved in the expression of a subset of these conditioned immunomodulatory effects.

  5. Interferon beta and vitamin D synergize to induce immunoregulatory receptors on peripheral blood monocytes of multiple sclerosis patients.

    Directory of Open Access Journals (Sweden)

    Anne Waschbisch

    Full Text Available Immunoglobulin-like transcript (ILT 3 and 4 are inhibitory receptors that modulate immune responses. Their expression has been reported to be affected by interferon, offering a possible mechanism by which this cytokine exerts its therapeutic effect in multiple sclerosis, a condition thought to involve excessive immune activity. To investigate this possibility, we measured expression of ILT3 and ILT4 on immune cells from multiple sclerosis patients, and in post-mortem brain tissue. We also studied the ability of interferon beta, alone or in combination with vitamin D, to induce upregulation of these receptors in vitro, and compared expression levels between interferon-treated and untreated multiple sclerosis patients. In vitro interferon beta treatment led to a robust upregulation of ILT3 and ILT4 on monocytes, and dihydroxyvitamin D3 increased expression of ILT3 but not ILT4. ILT3 was abundant in demyelinating lesions in postmortem brain, and expression on monocytes in the cerebrospinal fluid was higher than in peripheral blood, suggesting that the central nervous system milieu induces ILT3, or that ILT3 positive monocytes preferentially enter the brain. Our data are consistent with involvement of ILT3 and ILT4 in the modulation of immune responsiveness in multiple sclerosis by both interferon and vitamin D.

  6. 1,2,3-triazolyl amino acids as AMPA receptor ligands

    DEFF Research Database (Denmark)

    Stanley, Nathan J.; Pedersen, Daniel Sejer; Nielsen, Birgitte;

    2010-01-01

    The central nervous system glutamate receptors are an important target for drug discovery. Herein we report initial investigations into the synthesis and glutamate receptor activity of 1,2,3-triazolyl amino acids. Two compounds were found to be selective AMPA receptor ligands, which warrant further...

  7. Experimental and theoretical studies on the inclusion complexation of syringic acid with alpha-, beta-, gamma- and heptakis(2,6-di-O-methyl)-beta-cyclodextrin.

    Science.gov (United States)

    Song, Le Xin; Wang, Hai Ming; Xu, Peng; Yang, Yan; Zhang, Zi Qiang

    2008-04-01

    Intermolecular interactions of alpha-, beta-, gamma- and heptakis(2,6-di-O-methyl)-beta-cyclodextrin (CD) with syringic acid (Syr) in aqueous solution are investigated by fluorescence spectroscopy. The fluorescence intensity of Syr gradually increases with the addition of the CDs. The formation constants (K) of the host-guest inclusion complexes are determined using a nonlinear analysis. The association abilities of Syr with the CDs decrease in the order gamma->beta->alpha- approximately DMbeta-CD. Both the intrinsic binding abilities of the CDs and the structural effect of Syr are taken into consideration when comparing the K values. Based on the results of NMR experimental and theoretical PM3 calculations both in vacuo and in water, it is found that Syr stays near the wider rim of alpha-CD cavity. Both the number of substituted groups (NSG) in a guest and the molar volume ratio of the guest to host cavity (MVR) play an important role in forming the CD supramolecular complexes of a homologous series of phenol derivatives, such as 2-methoxylphenol (2-Mop), eugenol (Eug) and Syr, i.e., an appropriate NSG or MVR in an inclusion system, such as in 2-Mop-alpha-CD, Eug-beta-CD and Syr-gamma-CD systems, can maximize the intermolecular interaction between host and guest.

  8. Long-term exposure to IL-1beta enhances Toll-IL-1 receptor-mediated inflammatory signaling in murine airway hyperresponsiveness

    DEFF Research Database (Denmark)

    Zhang, Yaping; Xu, Cang-Bao; Cardell, Lars-Olaf

    2009-01-01

    Toll-interleukin-1 (Toll-IL-1) receptor signaling may play a key role in the development of airway hyperreactivity (AHR) and chronic airway inflammatory diseases such as asthma. Previously, we have demonstrated that pro-inflammatory cytokines, tumor necrosis factor-alpha (TNF-alpha) and interleukin......RNA expression following IL-1beta treatment. Immunohistochemistry confirmed that protein expression for CD14, RP105, MCP-1 and phosphorylated IkappaB-alpha were increased in both the airway epithelial and smooth muscle cells. In order to link the activation of Toll-IL-1 receptor-mediated inflammatory signal......-1beta (IL-1beta), induce AHR. However, the underlying intracellular signaling mechanisms that lead to AHR remain elusive. In order to see if the Toll-IL-1 receptor-mediated inflammatory signal pathways are involved in the development of AHR, the present study was designed to use a real-time PCR...

  9. Expression of glucocorticoid receptor, mineralocorticoid receptor, and 11beta-hydroxysteroid dehydrogenase 1 and 2 in the fetal and postnatal ovine hippocampus: ontogeny and effects of prenatal glucocorticoid exposure.

    Science.gov (United States)

    Sloboda, Deborah M; Moss, Timothy J M; Li, Shaofu; Matthews, Stephen G; Challis, John R G; Newnham, John P

    2008-05-01

    To determine the expression of glucocorticoid metabolizing and action genes in the hippocampus of fetal, neonatal, and adult sheep. Pregnant ewes (or their fetuses) received intramuscular injections of saline or betamethasone (BETA, 0-5 mg/kg) at 104, 111, 118, and/or 125 days of gestation (dG). Hippocampal tissue was collected prior to (75, 84, and 101 dG), during (109 and 116 dG), or after (121, 132, and 146 dG; 6 and 12 postnatal weeks; 3.5 years of age) saline or BETA injections. Hippocampal glucocorticoid receptor (GR), mineralocorticoid receptor (MR), and 11beta-hydroxysteroid dehydrogenase (11betaHSD)1 and 11betaHSD2 mRNA levels were determined using qRT-PCR. Control animals late in gestation demonstrated a decrease in mRNA encoding GR and 11betaHSD1, whereas 11betaHSD2 was undetectable, consistent with a damping of the negative feedback influence of circulating or locally produced cortisol on the hypothalamic-pituitary-adrenal (HPA) axis. BETA-administration had transient effects on fetal GR and MR, and early in postnatal life (12 weeks of age) 11betaHSD1 mRNA was increased. Hippocampal MR mRNA was elevated in adult offspring exposed to either one or four doses of maternal BETA (Pglucocorticoid negative feedback, facilitating increased preterm HPA activity and parturition. Adult offspring of BETA-treated mothers demonstrated increased MR and 11betaHSD2 mRNA, therefore it appears that exposure of fetus to high levels of synthetic glucocorticoids may have long-lasting effects on the hippocampal expression of HPA-related genes into adulthood.

  10. Purification of telluric acid for SNO+ neutrinoless double-beta decay search

    Energy Technology Data Exchange (ETDEWEB)

    Hans, S.; Rosero, R.; Hu, L. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Chkvorets, O. [Laurentian University, Sudbury (Canada); Chan, W.T.; Guan, S.; Beriguete, W. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Wright, A. [Queen University, Kingston (Canada); Ford, R. [SNOLAB, Creighton Mine, Sudbury (Canada); Chen, M.C. [Queen University, Kingston (Canada); Biller, S. [University of Oxford, Oxford OX1 3RH (United Kingdom); Yeh, M., E-mail: yeh@bnl.gov [Brookhaven National Laboratory, Upton, NY 11973 (United States)

    2015-09-21

    Tellurium-130 has the highest natural abundance of any double-beta decay isotopes. Recently it has been developed as a promising candidate for loading in liquid scintillator to explore the Majorana or Dirac nature of the neutrino through a search for neutrinoless double beta decay (0νββ). To this end, procedures have been developed to transfer tellurium ions into the organic liquid by a water-based loading technology. However, traces of naturally occurring radioactivity and cosmic-ray induced isotopes introduced into the scintillator with tellurium could produce undesirable contaminations in the {sup 130}Te 0νββ region. Measurements using various elemental spikes prepared from different chemical forms indicate that the uses of self-scavenging as well as acid and thermal recrystallization prior to the preparation of a tellurium-loaded liquid scintillator can deplete U and Th and several cosmic-activated isotopes from Te feedstock by a factor of 10{sup 2}–10{sup 3} in a single pass. The process is also found to improve the optical transmission in the blue region, sensible to the photomultiplier tube, by removing traces of colored impurities. In addition to the scintillator-based experiments, this cleansing scheme has potential applications to the production of radiopure tellurium crystals for other rare-event experiments.

  11. SIGNALLING THROUGH RETINOIC ACID RECEPTORS IN CARDIAC DEVELOPMENT: DOING THE RIGHT THINGS AT THE RIGHT TIMES

    OpenAIRE

    Xavier-Neto, José; Costa, Ângela M. Sousa; Figueira, Ana Carolina M.; Caiaffa, Carlo Donato; do Amaral, Fabio Neves; Peres, Lara Maldanis Cerqueira; da Silva, Bárbara Santos Pires; Santos, Luana Nunes; Moise, Alexander R.; Castillo, Hozana Andrade

    2014-01-01

    Retinoic acid (RA) is a terpenoid that is synthesized from Vitamin A/retinol (ROL) and binds to the nuclear receptors retinoic acid receptor (RAR)/retinoid X receptor (RXR) to control multiple developmental processes in vertebrates. The available clinic and experimental data provide uncontested evidence for the pleiotropic roles of RA signalling in development of multiple embryonic structures and organs such eyes, central nervous system, gonads, lungs and heart. The development of any of thes...

  12. TLR2 is a primary receptor for Alzheimer's amyloid beta peptide to trigger neuroinflammatory activation.

    NARCIS (Netherlands)

    Liu, S.; Liu, Y.; Hao, W.; Wolf, L.; Kiliaan, A.J.; Penke, B.; Rube, C.E.; Walter, J.; Heneka, M.T.; Hartmann, T.; Menger, M.D.; Fassbender, K.

    2012-01-01

    Microglia activated by extracellularly deposited amyloid beta peptide (Abeta) act as a two-edged sword in Alzheimer's disease pathogenesis: on the one hand, they damage neurons by releasing neurotoxic proinflammatory mediators (M1 activation); on the other hand, they protect neurons by triggering an

  13. Crystal structure of the human beta2 adrenergic G-protein-coupled receptor

    DEFF Research Database (Denmark)

    Rasmussen, Søren Gøgsig Faarup; Choi, Hee-Jung; Rosenbaum, Daniel M;

    2007-01-01

    was crystallized in a lipid environment when bound to an inverse agonist and in complex with a Fab that binds to the third intracellular loop. Diffraction data were obtained by high-brilliance microcrystallography and the structure determined at 3.4 A/3.7 A resolution. The cytoplasmic ends of the beta2AR...

  14. Antagonist of the amylin receptor blocks beta-amyloid toxicity in rat cholinergic basal forebrain neurons.

    Science.gov (United States)

    Jhamandas, Jack H; MacTavish, David

    2004-06-16

    Salvage of cholinergic neurons in the brain through a blockade of the neurotoxic effects of amyloidbeta protein (Abeta) is one of the major, but still elusive, therapeutic goals of current research in Alzheimer's disease (AD). To date, no receptor has been unequivocally identified for Abeta. Human amylin, which acts via a receptor composed of the calcitonin receptor-like receptor and a receptor-associated membrane protein, possesses amyloidogenic properties and has a profile of neurotoxicity that is strikingly similar to Abeta. In this study, using primary cultures of rat cholinergic basal forebrain neurons, we show that acetyl-[Asn30, Tyr32] sCT(8-37) (AC187), an amylin receptor antagonist, blocks Abeta-induced neurotoxicity. Treatment of cultures with AC187 before exposure to Abeta results in significantly improved neuronal survival as judged by MTT and live-dead cell assays. Quantitative measures of Abeta-evoked apoptotic cell death, using Hoechst and phosphotidylserine staining, confirm neuroprotective effects of AC187. We also demonstrate that AC187 attenuates the activation of initiator and effector caspases that mediate Abeta-induced apoptotic cell death. These data are the first to show that expression of Abeta toxicity may occur through the amylin receptor and suggest a novel therapeutic target for the treatment of AD. PMID:15201330

  15. Amino acid sequences and structures of chicken and turkey beta 2-microglobulin

    DEFF Research Database (Denmark)

    Welinder, K G; Jespersen, H M; Walther-Rasmussen, J;

    1991-01-01

    to human beta 2-microglobulin at 46 and 47 positions, respectively, and to bovine beta 2-microglobulin at 47 positions, i.e. there is about 47% identity between avian and mammalian beta 2-microglobulins. The known X-ray crystallographic structures of bovine beta 2-microglobulin and human HLA-A2 complex...... suggest that the seven chicken to turkey differences are exposed to solvent in the avian MHC class I complex. The key residues of beta 2-microglobulin involved in alpha chain contacts within the MHC class I molecule are highly conserved between chicken and man. This explains that heterologous human beta 2...

  16. "Oral ascorbic acid in combination with beta blockers in prevention of atrial fibrillation after Coronary Artery Bypass Graft "

    Directory of Open Access Journals (Sweden)

    Mousavi M

    2007-04-01

    Full Text Available Background: Adrenergic beta antagonists are not sufficient to prevent atrial fibrillation after coronary artery bypass graft (CABG. This study was designed to evaluate the effect of ascorbic acid as an adjunct to beta-blockers in prevention of post-CABG atrial fibrillation Methods: Patients who were more than 50 years old and scheduled to undergo CABG were included if they were treated with beta-blockers at least 1 week before surgery. Patients with previous history of atrial fibrillation, AV block, heart rate <50 /min, end-stage renal disease, severe pulmonary or liver disease and those who were taking digoxin or class I and III anti-arrhythmics or had pacemakers were not included. Ascorbic acid group were prescribed 2 gm of ascorbic acid, the night before the surgery, and 1 gm twice daily for 5 days after surgery. Beta blockers continued in both group after surgery. Telemetry monitoring was performed in ICU and Holter monitoring was performed for 4 days. Results: Fifty patients completed the study as ascorbic acid and 50 as control group. The population was 60.19 ± 7.14 years old and 67% were male. The incidence of postoperative atrial fibrillation was 4% in the ascorbic acid group and 26% in control group (odds ratio=0.119, 95% confidence interval: 0.025 to 0.558, P=0.002 Conclusion: Ascorbic acid is well-tolerated, relatively safe and seems effective. Therefore it can be prescribed as an adjunct to beta-blockers for prophylaxis of post-CABG atrial fibrillation.

  17. Positron emission tomography study on pancreatic somatostatin receptors in normal and diabetic rats with {sup 68}Ga-DOTA-octreotide: A potential PET tracer for beta cell mass measurement

    Energy Technology Data Exchange (ETDEWEB)

    Sako, Takeo [Division of Bio-function Dynamics Imaging, RIKEN Center for Life Science Technologies, 6-7-3 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo 650-0047 (Japan); Division of Molecular Imaging, Institute of Biomedical Research and Innovation, 2-2 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo 650-0047 (Japan); Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan); Hasegawa, Koki; Nishimura, Mie; Kanayama, Yousuke; Wada, Yasuhiro; Hayashinaka, Emi; Cui, Yilong; Kataoka, Yosky [Division of Bio-function Dynamics Imaging, RIKEN Center for Life Science Technologies, 6-7-3 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo 650-0047 (Japan); Senda, Michio [Division of Bio-function Dynamics Imaging, RIKEN Center for Life Science Technologies, 6-7-3 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo 650-0047 (Japan); Division of Molecular Imaging, Institute of Biomedical Research and Innovation, 2-2 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo 650-0047 (Japan); Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan); Watanabe, Yasuyoshi, E-mail: yywata@riken.jp [Division of Bio-function Dynamics Imaging, RIKEN Center for Life Science Technologies, 6-7-3 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo 650-0047 (Japan)

    2013-12-06

    Highlights: •PET images showed high uptake of {sup 68}Ga-DOTA-octreotide in the normal pancreas. •{sup 68}Ga-DOTA-octreotide specifically binds to somatostatin receptors in the pancreas. •The pancreatic uptake of {sup 68}Ga-DOTA-octreotide was decreased in the diabetic rats. •{sup 68}Ga-DOTA-octreotide could be a candidate PET probe to measure the beta cell mass. -- Abstract: Diabetes mellitus (DM) is a metabolic disorder characterized by hyperglycemia, and the loss or dysfunction of pancreatic beta cells has been reported before the appearance of clinical symptoms and hyperglycemia. To evaluate beta cell mass (BCM) for improving the detection and treatment of DM at earlier stages, we focused on somatostatin receptors that are highly expressed in the pancreatic beta cells, and developed a positron emission tomography (PET) probe derived from octreotide, a metabolically stable somatostatin analog. Octreotide was conjugated with 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA), a chelating agent, and labeled with {sup 68}Gallium ({sup 68}Ga). After intravenous injection of {sup 68}Ga-DOTA-octreotide, a 90-min emission scan of the abdomen was performed in normal and DM model rats. The PET studies showed that {sup 68}Ga-DOTA-octreotide radioactivity was highly accumulated in the pancreas of normal rats and that the pancreatic accumulation was significantly reduced in the rats administered with an excess amount of unlabeled octreotide or after treatment with streptozotocin, which was used for the chemical induction of DM in rats. These results were in good agreement with the ex vivo biodistribution data. These results indicated that the pancreatic accumulation of {sup 68}Ga-DOTA-octreotide represented specific binding to the somatostatin receptors and reflected BCM. Therefore, PET imaging with {sup 68}Ga-DOTA-octreotide could be a potential tool for evaluating BCM.

  18. Farnesoid X receptor, the bile acid sensing nuclear receptor, in liver regeneration

    Directory of Open Access Journals (Sweden)

    Guodong Li

    2015-03-01

    Full Text Available The liver is unique in regenerative potential, which could recover the lost mass and function after injury from ischemia and resection. The underlying molecular mechanisms of liver regeneration have been extensively studied in the past using the partial hepatectomy (PH model in rodents, where 2/3 PH is carried out by removing two lobes. The whole process of liver regeneration is complicated, orchestrated event involving a network of connected interactions, which still remain fully elusive. Bile acids (BAs are ligands of farnesoid X receptor (FXR, a nuclear receptor of ligand-activated transcription factor. FXR has been shown to be highly involved in liver regeneration. BAs and FXR not only interact with each other but also regulate various downstream targets independently during liver regeneration. Moreover, recent findings suggest that tissue-specific FXR also contributes to liver regeneration significantly. These novel findings suggest that FXR has much broader role than regulating BA, cholesterol, lipid and glucose metabolism. Therefore, these researches highlight FXR as an important pharmaceutical target for potential use of FXR ligands to regulate liver regeneration in clinic. This review focuses on the roles of BAs and FXR in liver regeneration and the current underlying molecular mechanisms which contribute to liver regeneration.

  19. Inducible Conditional Vascular-Specific Overexpression of Peroxisome Proliferator-Activated Receptor Beta/Delta Leads to Rapid Cardiac Hypertrophy

    Science.gov (United States)

    Wagner, Kay-Dietrich; Vukolic, Ana; Baudouy, Delphine; Michiels, Jean-François

    2016-01-01

    Peroxisome proliferator-activated receptors are nuclear receptors which function as ligand-activated transcription factors. Among them, peroxisome proliferator-activated receptor beta/delta (PPARβ/δ) is highly expressed in the heart and thought to have cardioprotective functions due to its beneficial effects in metabolic syndrome. As we already showed that PPARβ/δ activation resulted in an enhanced cardiac angiogenesis and growth without impairment of heart function, we were interested to determine the effects of a specific activation of PPARβ/δ in the vasculature on cardiac performance under normal and in chronic ischemic heart disease conditions. We analyzed the effects of a specific PPARβ/δ overexpression in endothelial cells on the heart using an inducible conditional vascular-specific mouse model. We demonstrate that vessel-specific overexpression of PPARβ/δ induces rapid cardiac angiogenesis and growth with an increase in cardiomyocyte size. Upon myocardial infarction, vascular overexpression of PPARβ/δ, despite the enhanced cardiac vessel formation, does not protect against chronic ischemic injury. Our results suggest that the proper balance of PPARβ/δ activation in the different cardiac cell types is required to obtain beneficial effects on the outcome in chronic ischemic heart disease. PMID:27057154

  20. Direct activation of GABAA receptors by substances in the organic acid fraction of Japanese sake.

    Science.gov (United States)

    Izu, Hanae; Shigemori, Kensuke; Eguchi, Masaya; Kawane, Shuhei; Fujii, Shouko; Kitamura, Yuji; Aoshima, Hitoshi; Yamada, Yasue

    2017-01-01

    We investigated the effect of substances present in Japanese sake on the response of ionotropic γ-aminobutyric acid (GABA)A receptors expressed in Xenopus oocytes. Sake was fractionated by ion-exchange chromatography. The fraction containing organic acids (OA fraction) showed agonist activities on the GABAA receptor. OA fractions from sake were analyzed by capillary electrophoresis time-of-flight mass spectrometry (CE-TOFMS). Of the 64 compounds identified, 13 compounds showed GABAA receptor agonist activities. Especially, l-lactic acid showed high agonist activity and its EC50 value was 37μM. Intraperitoneal injections of l-lactic acid, gluconic acid, and pyruvic acid (10, 10, and 5mg/kg BW, respectively), which showed agonistic activity on the GABAA receptor, led to significant anxiolytic effects during an elevated plus-maze test in mice. PMID:27507485

  1. Human adipose tissue blood flow during prolonged exercise, III. Effect of beta-adrenergic blockade, nicotinic acid and glucose infusion

    DEFF Research Database (Denmark)

    Bülow, J

    1981-01-01

    acid, during acute i.v. beta-adrenergic blockade by propranolol, and during continuous i.v. infusion of glucose. The most pronounced lipid mobilization and utilization during work was seen in the control experiments where ATBF rose 3-fold on average from the initial rest period to the third hour...

  2. Synthesis of the [beta]-D-glucosyl ester of [carbonyl-[sup 13]C]-indole-3-acetic acid

    Energy Technology Data Exchange (ETDEWEB)

    Jakas, A.; Magnus, V. (Rudjer Boskovic Inst., Zagreb (Croatia)); Horvat, S.; Sandberg, G. (Swedish Univ. of Agricultural Sciences, Uppsala (Sweden))

    1993-10-01

    An efficient, operationally simple synthetic approach to 1-O-([carbonyl-[sup 13]C]-indole-3'-ylacetyl)-[beta]-D-glucopyranose is described. The synthesis was carried out by fusing a fully benzylated 1-O-glucosylpseudourea intermediate with [carbonyl-[sup 13]C]-indole-3-acetic acid, followed by hydrogenolytic removal of the protective groups. (Author).

  3. Dextromethorphan and its metabolite dextrorphan block alpha3beta4 neuronal nicotinic receptors.

    Science.gov (United States)

    Hernandez, S C; Bertolino, M; Xiao, Y; Pringle, K E; Caruso, F S; Kellar, K J

    2000-06-01

    Dextromethorphan (DM), a structural analog of morphine and codeine, has been widely used as a cough suppressant for more than 40 years. DM is not itself a potent analgesic, but it has been reported to enhance analgesia produced by morphine and nonsteroidal anti-inflammatory drugs. Although DM is considered to be nonaddictive, it has been reported to reduce morphine tolerance in rats and to be useful in helping addicted subjects to withdraw from heroin. Here we studied the effects of DM on neuronal nicotinic receptors stably expressed in human embryonic kidney cells. Studies were carried out to examine the effects of DM on nicotine-stimulated whole cell currents and nicotine-stimulated (86)Rb(+) efflux. We found that both DM and its metabolite dextrorphan block nicotinic receptor function in a noncompetitive but reversible manner, suggesting that both drugs block the receptor channel. Consistent with blockade of the receptor channel, neither drug competed for the nicotinic agonist binding sites labeled by [(3)H]epibatidine. Although DM is approximately 9-fold less potent than the widely used noncompetitive nicotinic antagonist mecamylamine in blocking nicotinic receptor function, the block by DM appears to reverse more slowly than that by mecamylamine. These data indicate that DM is a useful antagonist for studying nicotinic receptor function and suggest that it might prove to be a clinically useful neuronal nicotinic receptor antagonist, possibly helpful as an aid for helping people addicted to nicotine to refrain from smoking, as well as in other conditions where blockade of neuronal nicotinic receptors would be helpful. PMID:10869398

  4. Evaluation of spirometry values in relation to beta-2-adrenergic receptor gene polymorphism

    OpenAIRE

    Poziomkowska-Gesicka, I; Dzieciolowska-Baran, E; Gawlikowska-Sroka, A; Slowik-Zylka, D; Sroczynski, T

    2010-01-01

    Introduction The vagus nerve plays a special role in the control of respiratory system activity which represents the parasympathetic part of the autonomic nervous system. A small bronchial innervation by the sympathetic system also is observed, and there is a significant expression of adrenergic receptors, in particular β2 receptors, in the airways. The development of genetics and molecular biology allows for a detailed study which can clarify the essential elements in the pathogenesis of man...

  5. Immunolocalization of estrogen receptor beta in the epididymis of mature and immature pigs.

    OpenAIRE

    Maggiolini, M.; L Siciliano; B Bilinska; CARPINO, A.; V Rago

    2004-01-01

    A growing body of evidence suggests a role of estrogens in the male reproduction via their specific estrogen receptors (ERalpha/ERbeta). Estrogen receptor distribution along the genital tract tissues has been described in different species, but it is unknown in the pig. Therefore, the aim of the present study was to localize ERbeta in the epididymis of mature and immature pigs (aged 2 and 18 months, respectively). Immunohistochemistry was carried out on paraffin-embedded tissues using a mouse...

  6. A case of impairment of mitochondrial fatty acid beta-oxidation.

    Science.gov (United States)

    Hasegawa, Tomonobu; Hori, Naoaki; Du, Wenlin

    2002-06-01

    We describe a patient with impairment of mitochondrial fatty acid P-oxidation. A Japanese baby boy was delivered in the 38th week of gestation by emergency cesarean section due to fetal asphyxia. His birth weight was 1,985 g (head circumference 31.0 cm (10th percentile). His Apgar scores were 3 and 5 at 1 min and 5 min, respectively. Blood glucose was 12 mg/dl at 1 hour after birth, requiring glucose administration. On day 1 his serum CK was 20,780 IU/l, which was thought to be due to asphyxia. His serum CK levels gradually began to decrease. At 3 months of age, he sucked poorly, had poor body weight gain, and muscle hypotonia was observed. On day 117 his general condition was impaired, and marked hepatomegaly was observed. The blood glucose level was 43 mg/dl. The patient's urine was negative for ketone bodies. His serum triglyceride level was 3,670 mg/dl. Abdominal CT scan revealed a fatty liver. Serum levels of acyl carnitine from very-long chain fatty acid increased. On day 118 he died due to ventricular fibrillation. On necropsy, massive lipid deposition was observed in the liver, cardiac muscle, kidney, skeletal muscle, and intestinal mucosa. The ratio of very-long chain acyl-CoA dehydrogenase (VLCAD) activity for C16/C8 fatty acid was 0.50 (normal control 1.29), suggesting abnormal VLCAD. He was diagnosed as having impairment of mitochondrial fatty acid beta-oxidation, presumably due to the VLCAD deficiency. PMID:12125906

  7. Association of estrogen receptor beta variants and serum levels of estradiol with risk of colorectal cancer: a case control study

    Directory of Open Access Journals (Sweden)

    Wu Huanlei

    2012-07-01

    Full Text Available Abstract Background Endogenous estrogens may play a vital role in colorectal tumorigenesis. Estrogen receptor beta is the predominant subtype which mediates the biological effect of estrogens, while loss of expression of estrogen receptor beta has been indicated as a common step in the development of colorectal cancer (CRC. Epidemiological studies have revealed several functional polymorphisms of estrogen receptor beta (ESR2 for cancer risk, but relevant study in CRC is limited, particularly in men. This study aimed to investigate the association of circulating estradiol and variations of ESR2 with CRC risk in men. Methods We initiated a case–control study consisting of 390 patients with CRC and 445 healthy controls in men only. We genotyped ESR2 single nucleotide polymorphisms (SNPs rs1256049 and rs4986938 and measured serum estradiol concentration using chemilluminescence immunoassay. Multivariable logistic regression model was performed to evaluate the associations between these variables and CRC risk. Results ESR2 rs1256049 CT/TT genotypes were associated with reduced risk of CRC (odds ratio [OR], 0.7, 95% confidence interval [CI], 0.5–1.0, while rs4986938 CT/TT genotypes were associated with increased risk of CRC (OR, 1.5, 95% CI, 1.0–2.1. In addition, the CRC risk increased with the number of risk genotypes of these two SNPs in a dose–response manner (Ptrend, 0.003. Specifically, subjects carrying risk genotypes of both SNPs had the highest risk of CRC (OR, 2.0, 95% CI, 1.3–3.3.. Moreover, serum estradiol concentration alone was associated with risk of CRC in men (OR, 1.2, 95% CI, 1.0–1.3. However, individuals presenting both rs4986938 CT/TT genotypes and high level of serum estradiol had a high risk of CRC (OR, 2.3, 95% CI, 1.4–3.9, compared with those presenting CC genotype and low level of serum estradiol. The similar joint results were not observed for SNP rs1256049. Conclusions These results suggest that endogenous

  8. High value of the radiobiological parameter Dq correlates to expression of the transforming growth factor beta type II receptor in a panel of small cell lung cancer cell lines

    DEFF Research Database (Denmark)

    Hougaard, S; Krarup, M; Nørgaard, P;

    1998-01-01

    Our panel of SCLC cell lines have previously been examined for their radiobiological characteristics and sensitivity to treatment with TGF beta 1. In this study we examined the possible correlations between radiobiological parameters and the expression of the TGF beta type II receptor (TGF beta-r...... role for the repair of radiation induced DNA damage in SCLC....

  9. The role of 14-3-3{beta} in transcriptional activation of estrogen receptor {alpha} and its involvement in proliferation of breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yoonseo; Kim, Hyungjin; Jang, Sung-Wuk [School of Life Sciences and Biotechnology, Korea University, Seoul 136-701 (Korea, Republic of); Ko, Jesang, E-mail: jesangko@korea.ac.kr [School of Life Sciences and Biotechnology, Korea University, Seoul 136-701 (Korea, Republic of)

    2011-10-14

    Highlights: {yields} 14-3-3{beta} interacts with ER{alpha} and the interaction is Akt-dependent. {yields} 14-3-3{beta} regulates the transcriptional activity of ER{alpha} in a ligand-dependent manner. {yields} 14-3-3{beta} increases expressions of ER{alpha} target genes. {yields} 14-3-3{beta} increases breast cancer cell proliferation. -- Abstract: The estrogen receptor (ER) functions as a transcription factor that mediates the effects of estrogen. ER{alpha}, which plays a crucial role in the development and progression of breast cancer, is activated by estrogen binding, leading to receptor phosphorylation, dimerization, and recruitment of co-activators and chaperons to the estrogen-bound receptor complex. The 14-3-3 proteins bind to target proteins via phosphorylation and influence many cellular events by altering their subcellular localization or acting as a chaperone. However, regulation of ER{alpha} expression and transactivation by the 14-3-3 proteins has not been reported. We demonstrate that 14-3-3{beta} functions as a positive regulator of ER{alpha} through a direct protein-protein interaction in an estrogen-dependent manner. Ectopic expression of 14-3-3{beta} stimulated ER{alpha}-mediated transcriptional activity in MCF-7 breast cancer cells. Enhanced ER{alpha} transcriptional activity due to 14-3-3{beta} increased the expressions of the endogenous ER{alpha} target genes, leading to proliferation of breast cancer cells. We suggest that 14-3-3{beta} has oncogenic potential in breast cancer via binding to ER{alpha} and activation of the transcriptional activity of ER{alpha}.

  10. Molecular characterization of thyroid hormone receptor beta from Schistosoma japonicum and assessment of its potential as a vaccine candidate antigen against schistosomiasis in BALB/c mice

    OpenAIRE

    Qiu Chunhui; Liu Shengfa; Hong Yang; Fu Zhiqiang; Wei Meimei; Ai Dezhou; Lin Jiaojiao

    2012-01-01

    Abstract Background Thyroid hormones (TH) modulate growth, development and differentiation and metabolic processes by interacting with thyroid hormone receptors (THRs). The purpose of this study was to identify a novel thyroid hormone receptor beta encoding gene of Schistosoma japonicum (SjTHRβ) and to investigate its potential as a vaccine candidate antigen against schistosomiasis in BALB/c mice. Methods The full-length cDNA sequence of SjTHRβ, its gene organization, and its transcript level...

  11. Analysis of beta, gamma, and delta T-cell receptor genes in mycosis fungoides and Sezary syndrome.

    Science.gov (United States)

    Whittaker, S J; Smith, N P; Jones, R R; Luzzatto, L

    1991-10-01

    The authors have analyzed the configuration of immunoglobulin (Ig) and beta, gamma and delta T-cell receptor (TCR) genes in DNA extracted from skin, lymph nodes, and peripheral blood mononuclear cells obtained from 41 patients with mycosis fungoides (MF), 14 patients with Sezary syndrome, and 13 patients with benign inflammatory dermatoses. No discrete rearranged bands (DRB) were detected in patients with inflammatory dermatoses. In tissue DNA from 19 patients with MF DRB were detected with beta and gamma, but not delta TCR probes. Only one patient with MF had a rearrangement of gamma and delta with germ line beta TCR genes. In 13 patients multiple biopsies were analyzed and DRB, when present, were identical in different lesions from individual patients. In three patients analysis of DNA from dermatopathic lymph nodes did not reveal DRB. Analysis of peripheral blood DNA from 24 patients revealed a discrete rearrangement of the gamma TCR gene in four patients and both beta and gamma genes in four additional patients. In MF DRB were detected more frequently with advancing stage of disease in tissues (P less than 0.01) but not in peripheral blood (P equals 0.36). Of 14 patients with Sezary syndrome, eight had DRB in peripheral blood DNA with both beta and gamma probes and in three of these patients identical DRB were also detected in DNA from skin biopsy samples. In contrast, DRB were not detected in the peripheral blood of the other six patients. In both MF and Sezary syndrome there was no restricted usage of particular V gamma genes. These results indicate that in MF (1) T-cell clones can be detected in skin biopsy specimens from the majority of patients with early stage disease, (2) gamma delta T-cell clones are only rarely found, and (3) TCR gene analysis can detect T-cell clones in the peripheral blood with a greater degree of specificity than conventional light microscopic study. In Sezary syndrome these studies also suggest that a subset of patients have a

  12. The retinoic acid receptor agonist Am80 increases hippocampal ADAM10 in aged SAMP8 mice.

    Science.gov (United States)

    Kitaoka, Kazuyoshi; Shimizu, Noriyuki; Ono, Koji; Chikahisa, Sachiko; Nakagomi, Madoka; Shudo, Koichi; Ishimura, Kazunori; Séi, Hiroyoshi; Yoshizaki, Kazuo

    2013-09-01

    The retinoic acid (RA, a vitamin A metabolite) receptor (RAR) is a transcription factor. Vitamin A/RA administration improves the Alzheimer's disease (AD)- and age-related attenuation of memory/learning in mouse models. Recently, a disintegrin and metalloproteinase domain-containing protein 10 (ADAM10) was identified as a key molecule in RA-mediated anti-AD mechanisms. We investigated the effect of chronic administration of the RAR agonist Am80 (tamibarotene) on ADAM10 expression in senescence-accelerated mice (SAMP8). Moreover, we estimated changes in the expression of the amyloid precursor protein (APP), amyloid beta (Aβ), and hairy/enhancer of split (Hes), which are mediated by ADAM10. Spatial working memory and the levels of a hippocampal proliferation marker (Ki67) were also assessed in these mice. ADAM10 mRNA and protein expression was significantly reduced in the hippocampus of 13-month-old SAMP8 mice; their expression improved significantly after Am80 administration. Further, after Am80 administration, the expression levels of Hes5 and Ki67 were restored and the deterioration of working memory was suppressed, whereas APP and Aβ levels remained unchanged. Our results suggest that Am80 administration effectively improves dementia by activating the hippocampal ADAM10-Notch-Hes5 proliferative pathway. PMID:23624141

  13. [Serumconcentrations of non esterified fatty acids during operative stress and blockade of betaadrenergic receptors (author's transl)].

    Science.gov (United States)

    Knitza, R; Clasen, R; Kunz, C

    1978-11-01

    Every stress reaction leads to an increased, hormonelly induced mobilisation of fatty acids, the extent of which may be considered as a parameter of the aggression mechanism. In 15 patients with idiopathic trigeminal neuralgia, who were operated under neurolepthypalgesia, the problem of quantitative alterations of the concentration pattern of fatty acids was investigated during the operation. In contrast to some reports of the literature, the increase of the concentration of total fatty acids was due to corresponding increases of all individual fatty acids. By preoperative administration of the beta-adrenergic blocking agent Pindolol the increase of fatty acids was reduced without a qualitative shifting of individual fatty acids. PMID:30855

  14. [Central effects of five beta-adrenergic receptor blockers in healthy volunteers: a quantitative EEG study].

    Science.gov (United States)

    Sabot, C; Pechadre, J C; Beudin, P; Lauxerois, M; Trolese, J F; Kantelip, J P; Ducher, J L; Gibert, J

    1989-03-01

    The effects of five beta blockers on the central nervous system of healthy subjects was studied by computerized EEG analysis. All subjects underwent continuous recording with a Holter magnetic type recorder during the experimental period. For 10 consecutive days, five groups of subjects received alternately placebo and the beta blockers acebutolol 600 mg, carteolol 20 mg, metoprolol 200 mg, pindolol 30 mg and sotalol 320 mg. EEG recordings (C4/P4, P4/02 and C3/P3, P3/01) lasting 5 min were made between 8.30 and 9.30 a.m. Subjects were at rest with eyes closed and there was no vigilance control. The signal was recorded on a magnetic tape recorder and then processed by Nicolet MED 80 system. Comparisons of absolute and relative powers and of average frequencies were then made between the different sequences and groups. The possible correlations between the changes observed in the power spectrum and the clinical, pharmacological and pharmacokinetic specific properties of each beta blocker are discussed.

  15. A Specific Cholesterol Binding Site Is Established by the 2.8 Å Structure of the Human [beta][subscript 2]-Adrenergic Receptor

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, Michael A.; Cherezov, Vadim; Griffith, Mark T.; Roth, Christopher B.; Jaakola, Veli-Pekka; Chien, Ellen Y.T.; Velasquez, Jeffrey; Kuhn, Peter; Stevens, Raymond C. (Scripps)

    2008-07-08

    The role of cholesterol in eukaryotic membrane protein function has been attributed primarily to an influence on membrane fluidity and curvature. We present the 2.8 {angstrom} resolution crystal structure of a thermally stabilized human {beta}{sub 2}-adrenergic receptor bound to cholesterol and the partial inverse agonist timolol. The receptors pack as monomers in an antiparallel association with two distinct cholesterol molecules bound per receptor, but not in the packing interface, thereby indicating a structurally relevant cholesterol-binding site between helices I, II, III, and IV. Thermal stability analysis using isothermal denaturation confirms that a cholesterol analog significantly enhances the stability of the receptor. A consensus motif is defined that predicts cholesterol binding for 44% of human class A receptors, suggesting that specific sterol binding is important to the structure and stability of other G protein-coupled receptors, and that this site may provide a target for therapeutic discovery.

  16. Angiopoietin-like 4 mediates PPAR delta effect on lipoprotein lipase-dependent fatty acid uptake but not on beta-oxidation in myotubes.

    Directory of Open Access Journals (Sweden)

    Marius R Robciuc

    Full Text Available Peroxisome proliferator-activated receptor (PPAR delta is an important regulator of fatty acid (FA metabolism. Angiopoietin-like 4 (Angptl4, a multifunctional protein, is one of the major targets of PPAR delta in skeletal muscle cells. Here we investigated the regulation of Angptl4 and its role in mediating PPAR delta functions using human, rat and mouse myotubes. Expression of Angptl4 was upregulated during myotubes differentiation and by oleic acid, insulin and PPAR delta agonist GW501516. Treatment with GW501516 or Angptl4 overexpression inhibited both lipoprotein lipase (LPL activity and LPL-dependent uptake of FAs whereas uptake of BSA-bound FAs was not affected by either treatment. Activation of retinoic X receptor (RXR, PPAR delta functional partner, using bexarotene upregulated Angptl4 expression and inhibited LPL activity in a PPAR delta dependent fashion. Silencing of Angptl4 blocked the effect of GW501516 and bexarotene on LPL activity. Treatment with GW501516 but not Angptl4 overexpression significantly increased palmitate oxidation. Furthermore, Angptl4 overexpression did not affect the capacity of GW501516 to increase palmitate oxidation. Basal and insulin stimulated glucose uptake, glycogen synthesis and glucose oxidation were not significantly modulated by Angptl4 overexpression. Our findings suggest that FAs-PPARdelta/RXR-Angptl4 axis controls the LPL-dependent uptake of FAs in myotubes, whereas the effect of PPAR delta activation on beta-oxidation is independent of Angptl4.

  17. Neu1 desialylation of sialyl alpha-2,3-linked beta-galactosyl residues of TOLL-like receptor 4 is essential for receptor activation and cellular signaling.

    Science.gov (United States)

    Amith, Schammim Ray; Jayanth, Preethi; Franchuk, Susan; Finlay, Trisha; Seyrantepe, Volkan; Beyaert, Rudi; Pshezhetsky, Alexey V; Szewczuk, Myron R

    2010-02-01

    The ectodomain of TOLL-like receptors (TLR) is highly glycosylated with several N-linked gylcosylation sites located in the inner concave surface. The precise role of these sugar N-glycans in TLR receptor activation is unknown. Recently, we have shown that Neu1 sialidase and not Neu2, -3 and -4 forms a complex with TLR-2, -3 and -4 receptors on the cell-surface membrane of naïve and activated macrophage cells (Glycoconj J DOI 10.1007/s10719-009-9239-8). Activation of Neu1 is induced by TLR ligands binding to their respective receptors. Here, we show that endotoxin lipopolysaccharide (LPS)-induced MyD88/TLR4 complex formation and subsequent NFkappaB activation is dependent on the removal of alpha-2,3-sialyl residue linked to beta-galactoside of TLR4 by the Neu1 activity associated with LPS-stimulated live primary macrophage cells, macrophage and dendritic cell lines but not with primary Neu1-deficient macrophage cells. Exogenous alpha-2,3 sialyl specific neuraminidase (Streptoccocus pneumoniae) and wild-type T. cruzi trans-sialidase (TS) but not the catalytically inactive mutant TSAsp98-Glu mediate TLR4 dimerization to facilitate MyD88/TLR4 complex formation and NFkappaB activation similar to those responses seen with LPS. These same TLR ligand-induced NFkappaB responses are not observed in TLR deficient HEK293 cells, but are re-established in HEK293 cells stably transfected with TLR4/MD2, and are significantly inhibited by alpha-2,3-sialyl specific Maackia amurensis (MAL-2) lectin, alpha-2,3-sialyl specific galectin-1 and neuraminidase inhibitor Tamiflu but not by alpha-2,6-sialyl specific Sambucus nigra lectin (SNA). Taken together, the findings suggest that Neu1 desialylation of alpha-2,3-sialyl residues of TLR receptors enables in removing a steric hinderance to receptor association for TLR activation and cellular signaling. PMID:19796680

  18. L-653,328: an ocular hypotensive agent with modest beta receptor blocking activity

    Energy Technology Data Exchange (ETDEWEB)

    Sugrue, M.F.; Gautheron, P.; Grove, J.; Mallorga, P.; Viader, M.P.; Baldwin, J.J.; Ponticello, G.S.; Varga, S.L.

    1988-05-01

    L-653,328 is the acetate ester of L-652,698 ((S)-3-tert-butylamino-1-(4-(2(hydroxy)ethyl)phenoxy)2-propanol). The penetration of L-652,698 into the albino rabbit eye was enhanced when the compound was instilled as its prodrug acetate ester. The instillation (one drop of 50 microliter) of 0.01, 0.05 and 0.1% solutions of L-653,328 significantly decreased in a dose-dependent manner the elevated intraocular pressure (IOP) of alpha-chymotrypsinized rabbits by 3.2, 4.7 and 6.1 mm Hg, respectively. A 0.01% solution of L-652,698 failed to significantly lower IOP, whereas this dose of timolol (3.8 mm Hg) and betaxolol (3.3 mm Hg) was effective. L-652,698 was active at 0.05% and 0.1%. Extraocular beta-adrenoceptor blockade was quantified in ganglion-blocked, conscious rabbits by determining effects on heart rate and blood pressure changes to i.v. isoproterenol (0.5 microgram/kg). Doses of timolol blocking isoproterenol-induced hypotension and tachycardia by 50% were 0.0065% and 0.03%, respectively. The corresponding doses for betaxolol were greater than 3% (43% inhibition) and 0.3%. Heart rate and blood pressure changes to isoproterenol were blocked by 18 and 36%, respectively, after the instillation of a 3% solution of L-653,328. The reduced propensity of L-653,328 for extraocular beta-adrenoceptor blockade stems from the modest affinity of L-652,698, its active moiety, for beta-adrenoceptors. The Ki values of L-652,698 for displacement of 125I-iodocyanopindolol binding to beta 1-(left ventricle) and beta 2-binding sites (iris + ciliary body) in the rabbit were 5.7 microM and 7.3 microM, respectively. In marked contrast, the corresponding values for timolol were 12 nM and 1.8 nM.

  19. Somatostatin-receptor-targeted {alpha}-emitting {sup 213}Bi is therapeutically more effective than {beta}{sup -}-emitting {sup 177}Lu in human pancreatic adenocarcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Nayak, Tapan K. [Radiopharmaceutical Sciences Program, College of Pharmacy, University of New Mexico, Albuquerque, NM 87131-0001 (United States); Department of Cell Biology and Physiology, School of Medicine, University of New Mexico, Albuquerque, NM 87131 (United States); Norenberg, Jeffrey P. [Radiopharmaceutical Sciences Program, College of Pharmacy, University of New Mexico, Albuquerque, NM 87131-0001 (United States)]. E-mail: jpnoren@unm.edu; Anderson, Tamara L. [Radiopharmaceutical Sciences Program, College of Pharmacy, University of New Mexico, Albuquerque, NM 87131-0001 (United States); Prossnitz, Eric R. [Department of Cell Biology and Physiology, School of Medicine, University of New Mexico, Albuquerque, NM 87131 (United States); Stabin, Michael G. [Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN 37232 (United States); Atcher, Robert W. [Radiopharmaceutical Sciences Program, College of Pharmacy, University of New Mexico, Albuquerque, NM 87131-0001 (United States); Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2007-02-15

    Introduction: Advance clinical cancer therapy studies of patients treated with somatostatin receptor (sstr)-targeted [DOTA{sup 0}-Tyr{sup 3}]octreotide (DOTATOC) labeled with low-linear-energy-transfer (LET) {beta}{sup -}-emitters have shown overall response rates in the range of 15-33%. In order to improve outcomes, we sought to compare the therapeutic effectiveness of sstr-targeted high-LET {alpha}-emitting {sup 213}Bi to that of low-LET {beta}{sup -}-emitting {sup 177}Lu by determining relative biological effectiveness (RBE) using the external {gamma}-beam of {sup 137}Cs as reference radiation. Methods: Sstr-expressing human pancreatic adenocarcinoma Capan-2 cells and A549 control cells were used for this study. The effects of different radiation doses of {sup 213}Bi and {sup 177}Lu labeled to 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid and sstr-targeted DOTATOC were investigated with a clonogenic cell survival assay. Apoptosis was measured using the Cell Death Detection ELISA{sup PLUS} 10x kit. Results: Using equimolar DOTATOC treatment with concurrent irradiation with a {sup 137}Cs source as reference radiation, the calculated RBE of [{sup 213}Bi]DOTATOC was 3.4, as compared to 1.0 for [{sup 177}Lu]DOTATOC. As measured in terms of absorbance units, [{sup 213}Bi]DOTATOC caused a 2.3-fold-greater release of apoptosis-specific mononucleosomes and oligonucleosomes than [{sup 177}Lu]DOTATOC at the final treatment time of 96 h (P<.001) in sstr-expressing Capan-2 cells. Conclusions: In conclusion, at the same absorbed dose, [{sup 213}Bi]DOTATOC is therapeutically more effective in decreasing survival than is [{sup 177}Lu]DOTATOC in human pancreatic adenocarcinoma cells due to its comparatively higher RBE.

  20. Polymorphism at the ovine beta3-adrenergic receptor locus: associations with birth weight, growth rate, carcass composition and cold survival.

    Science.gov (United States)

    Forrest, R H; Hickford, J G H; Hogan, A; Frampton, C

    2003-02-01

    The beta3-adrenergic receptors (ADRB3s) are predominantly found on the surface of adipocytes and are the major mediators of the lipolytic and thermogenic effects of high catecholamine concentrations. Polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) analysis of part of the ovine beta3-adrenergic receptor gene (ADRB3) intron was used to screen 12 large Merino half-sib families for sequence variation. Six different alleles that segregated in a Mendelian fashion were observed. The genetic basis for the allelic differences were identified by sequencing the ADRB3 (coding and non-coding regions) from animals that were homozygous for each of the alleles. Five sire lines (two Merino x Merino, two Merino x Coopworth, one Dorset Down x Coopworth) provided phenotypic and genotypic data used to ascertain the effects of allelic variation at the ADRB3 locus on birth weight, weaning weight, growth rate (up until weaning), carcass composition at 63 days post-weaning and cold survival. Statistical analyses within each half-sib family showed that in some sire lines (S13, S15, and S17) the inheritance of a particular allele was associated with increased birth weights and/or increased growth rates up until weaning. The inheritance of a particular sire allele was associated with fatter carcasses in sire line S16. Chi-squared analysis revealed the association of the E allele with cold survival and the D allele with cold-related mortality in sire line S14. Such associations support the hypothesis that ADRB3s are involved in energy homeostasis. With more research, the variation detected at the ADRB3 locus may assist in the genetic selection for desirable animal production traits.

  1. Ultrastructural characterization of noradrenergic- and beta-adrenergic receptor-containing profiles in the lateral nucleus of the amygdala

    Directory of Open Access Journals (Sweden)

    Claudia Farb

    2010-10-01

    Full Text Available Norepinephrine (NE is thought to play a key role in fear and anxiety, but its role in amygdala-dependent Pavlovian fear conditioning, a major model for understanding the neural basis of fear, is poorly understood. The lateral nucleus of the amygdala (LA is a critical brain region for fear learning and regulating the effects of stress on memory. To understand better the cellular mechanisms of NE and its adrenergic receptors in the LA, we used antibodies directed against dopamine beta-hydroxylase (DβH, the synthetic enzyme for NE, or against two different isoforms of the beta-adrenergic receptors (βARs, one that predominately recognizes neurons (βAR 248 and the other astrocytes (βAR 404, to characterize the microenvironments of DβH and βAR. By electron microscopy, most DβH terminals did not make synapses, but when they did, they formed both asymmetric and symmetric synapses. By light microscopy, βARs were present in both neurons and astrocytes. Confocal microscopy revealed that both excitatory and inhibitory neurons express βAR248. By electron microscopy, βAR 248 was present in neuronal cell bodies, dendritic shafts and spines, and some axon terminals and astrocytes. When in dendrites and spines, βAR 248 was frequently concentrated along plasma membranes and at post-synaptic densities of asymmetric (excitatory synapses. βAR 404 was expressed predominately in astrocytic cell bodies and processes. These astrocytic processes were frequently interposed between unlabeled terminals or ensheathed asymmetric synapses. Our findings provide a morphological basis for understanding ways in which NE may modulate transmission by acting via synaptic or non-synaptic mechanisms in the LA.

  2. Conversion of agonist site to metal-ion chelator site in the beta(2)-adrenergic receptor

    DEFF Research Database (Denmark)

    Elling, C E; Thirstrup, K; Holst, Birgitte;

    1999-01-01

    in the mutant receptors not by normal catecholamine ligands but instead either by free zinc ions or by zinc or copper ions in complex with small hydrophobic metal-ion chelators. Chelation of the metal ions by small hydrophobic chelators such as phenanthroline or bipyridine protected the cells from the toxic...... effect of, for example Cu(2+), and in several cases increased the affinity of the ions for the agonistic site. Wash-out experiments and structure-activity analysis indicated, that the high-affinity chelators and the metal ions bind and activate the mutant receptor as metal ion guided ligand complexes....... Because of the well-understood binding geometry of the small metal ions, an important distance constraint has here been imposed between TM-III and -VII in the active, signaling conformation of 7TM receptors. It is suggested that atoxic metal-ion chelator complexes could possibly in the future be used...

  3. Cloning of T-cell antigen receptor beta chain cDNAs from Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Hordvik, I; Jacob, A L; Charlemagne, J; Endresen, C

    1996-01-01

    Atlantic salmon (Salmo salar) cDNAs encoding the T-cell antigen receptor beta chain (TCRB) were isolated from leukocyte RNA by reverse transcription - polymerase chain reaction (RT-PCR). Twenty-five distinct cDNA fragments covering the variable (V) - diversity (D) - joining (J) junction and part of the constant (C) region were characterized; the sequences of which indicate interchangeable V/D/J usage and expression in the context of one TCRBC gene. Full-length TCRBC sequence information was derived from a leukocyte cDNA library. Key residues of the salmon TCRBC region are in good agreement with those of other species. One distinct exception is the absence of the hinge region cysteine residue which is involved in covalent bonding between the alpha and beta chain in mammalian TCRs. As in amphibian and avian species, the salmon TCRBC membrane proximal region is considerably shorter than the mammalian. An octamer sequence (GGACAGGG) very similar to amphibian, avian, and mammalian D sequences could be recognized in the VDJ junctions from salmon. The pattern of VDJ variability also indicates that mechanisms like trimming and addition occur in fish as in higher vertebrates. Compared with mammals, a relatively high frequency (32%) of the VDJ junctions in salmon were out of frame. PMID:8881032

  4. AT1-IR-beta Association: A New Mechanism for the Inhibition of Insulin Receptor Function in Breast Cancer

    Directory of Open Access Journals (Sweden)

    Lakshmi Pulakat

    2008-01-01

    Full Text Available Epidemiological evidence show that increased mortality in breast cancer is linked to hypertension and insulin resistance. Because Angiotensin II (Ang II, a hormone implicated in hypertension and insulin resistance, is a normal mitogen for breast tissue and elevated expression of the Ang II receptor AT1 is seen in breast cancer, we analyzed the effects of Ang II exposure on the functions of IR in human breast cancer cell line MCF-7. Exposure of MCF-7 to Ang II for 2 hours a significantly reduced 125I-insulin binding to IR, and b induced co-immuno-precipitation of the AT1 with IR-beta subunit. These Ang II-mediated effects on IR were inhibited by the AT1 antagonist losartan, and were not observed when exposure time was below 1-hour. These observations suggest extended exposure to Ang II have detrimental effects on insulin binding to IR that were not discovered in the previous studies where Ang II-exposure of insulin responsive cells was performed for periods less than one hour. In addition, they suggest a novel mechanism that involves AT1-IR-beta association for the inhibition of insulin binding to IR in response to extended exposure (2-hours of breast cancer cells to elevated levels of Ang II (as seen in hypertensive patients, and provides a molecular link for the inhibition of normal IR signaling by Ang II in breast cancer.

  5. Selective Chemical Conversion of Sugars in Aqueous Solutions without Alkali to Lactic Acid Over a Zn-Sn-Beta Lewis Acid-Base Catalyst

    Science.gov (United States)

    Dong, Wenjie; Shen, Zheng; Peng, Boyu; Gu, Minyan; Zhou, Xuefei; Xiang, Bo; Zhang, Yalei

    2016-05-01

    Lactic acid is an important platform molecule in the synthesis of a wide range of chemicals. However, in aqueous solutions without alkali, its efficient preparation via the direct catalysis of sugars is hindered by a side dehydration reaction to 5-hydroxymethylfurfural due to Brønsted acid, which originates from organic acids. Herein, we report that a previously unappreciated combination of common two metal mixed catalyst (Zn-Sn-Beta) prepared via solid-state ion exchange synergistically promoted this reaction. In water without a base, a conversion exceeding 99% for sucrose with a lactic acid yield of 54% was achieved within 2 hours at 190 °C under ambient air pressure. Studies of the acid and base properties of the Zn-Sn-Beta zeolite suggest that the introduction of Zn into the Sn-Beta zeolite sequentially enhanced both the Lewis acid and base sites, and the base sites inhibited a series of side reactions related to fructose dehydration to 5-hydroxymethylfurfural and its subsequent decomposition.

  6. Characterization of DNA Binding and Retinoic Acid Binding Properties of Retinoic Acid Receptor

    Science.gov (United States)

    Yang, Na; Schule, Roland; Mangelsdorf, David J.; Evans, Ronald M.

    1991-05-01

    High-level expression of the full-length human retinoic acid receptor (RAR) α and the DNA binding domain of the RAR in Escherichia coli was achieved by using a T7 RNA polymerase-directed expression system. After induction, full-length RAR protein was produced at an estimated level of 20% of the total bacterial proteins. Both intact RAR molecules and the DNA binding domain bind to the cognate DNA response element with high specificity in the absence of retinoic acid. However, this binding is enhanced to a great extent upon the addition of eukaryotic cell extracts. The factor responsible for this enhancement is heat-sensitive and forms a complex with RAR that binds to DNA and exhibits a distinct migration pattern in the gel-mobility-shift assay. The interaction site of the factor with RAR is localized in the 70-amino acid DNA binding region of RAR. The hormone binding ability of the RARα protein was assayed by a charcoal absorption assay and the RAR protein was found to bind to retinoic acid with a K_d of 2.1 x 10-10 M.

  7. Folate receptor beta as a potential delivery route for novel folate antagonists to macrophages in the synovial tissue of rheumatoid arthritis patients

    NARCIS (Netherlands)

    J.W. van der Heijden; R. Oerlemans; B.A.C. Dijkmans; H. Qi; C.J. van der Laken; W.F. Lems; A.L. Jackman; M.C. Kraan; P.P. Tak; M. Ratnam; G. Jansen

    2009-01-01

    OBJECTIVE: To determine the expression of folate receptor beta (FRbeta) in synovial biopsy tissues and peripheral blood lymphocytes from rheumatoid arthritis (RA) patients and to identify novel folate antagonists that are more selective in the targeting and internalization of FRbeta than methotrexat

  8. Lack of associations between serum leptin, a polymorphism in the gene for the beta(3)-adrenergic receptor and glucose tolerance in the Dutch population.

    NARCIS (Netherlands)

    Janssen, JAMJL; Koper, JW; Stolk, RP; Englaro, P; Uitterlinden, AG; Huang, Q; van Leeuwen, JPTM; Blum, WF; Attanasio, AMF; Pols, HAP; Grobbee, DE; de Jong, FH; Lamberts, SWJ

    1998-01-01

    BACKGROUND The associations between leptin levels and the prevalence of a polymorphism in the beta(3)-adrenergic receptor were studied in a cross-sectional analysis of 600 participants in a population-based study, which were stratified for glucose tolerance by an oral glucose tolerance test. METHODS

  9. The nicotinic alpha7 acetylcholine receptor agonist ssr180711 is unable to activate limbic neurons in mice overexpressing human amyloid-beta1-42

    DEFF Research Database (Denmark)

    Soderman, A.; Spang-Thomsen, Mogens; Hansen, H.;

    2008-01-01

    Recent studies have demonstrated that amyloid-beta1-42 (Abeta1-42) binds to the nicotinergic alpha7 acetylcholine receptor (alpha7 nAChR) and that the application of Abeta1-42 to cells inhibits the function of the alpha7 nAChR. The in vivo consequences of the pharmacological activation of the alpha...

  10. Studies of associations between the Arg389Gly polymorphism of the beta1-adrenergic receptor gene (ADRB1) and hypertension and obesity in 7677 Danish white subjects

    DEFF Research Database (Denmark)

    Gjesing, A P; Andersen, G; Albrechtsen, A;

    2007-01-01

    Activation of the beta(1)-adrenergic receptor (ADRB1) causes increased lipolysis in adipose tissue and enhances cardiac output. Analysis of the association of the functional ADRB1 Arg389Gly variant with obesity and hypertension has given ambiguous results. To clarify the potential impact...

  11. Beta-adrenergic receptor agonists induce the release of granulocyte chemotactic protein-2, oncostatin M, and vascular endothelial growth factor from macrophages

    NARCIS (Netherlands)

    Verhoeckx, K.C.M.; Doornbos, R.P.; Witkamp, R.F.; Greef, de J.; Rodenburg, R.J.T.

    2006-01-01

    Vascular endothelial growth factor (VEGF), oncostatin M (OSM), and granulocyte chemotactic protein-2 (GCP-2/CXCL6) are up-regulated in U937 macrophages and peripheral blood macrophages exposed to LPS, beta-adrenergic receptor (ß2-AR) agonists (e.g. zilpaterol, and clenbuterol) and some other agents

  12. Beta-adrenergic receptor agonists induce the release of granulocyte chemotactic protein-2, oncostatin M, and vascular endothelial growth factor from macrophages

    NARCIS (Netherlands)

    Verhoeckx, K.C.M.; Doornbos, R.P.; Witkamp, R.F.; Greef, J. van der; Rodenburg, R.J.T.

    2006-01-01

    Vascular endothelial growth factor (VEGF), oncostatin M (OSM), and granulocyte chemotactic protein-2 (GCP-2/CXCL6) are up-regulated in U937 macrophages and peripheral blood macrophages exposed to LPS, beta-adrenergic receptor (β2-AR) agonists (e.g. zilpaterol, and clenbuterol) and some other agents

  13. TGF-beta receptor 2 downregulation in tumour-associated stroma worsens prognosis and high-grade tumours show more tumour-associated macrophages and lower TGF-beta1 expression in colon carcinoma: a retrospective study

    Directory of Open Access Journals (Sweden)

    Papadopoulos Thomas

    2007-08-01

    Full Text Available Abstract Background Histological phenotype and clinical behaviour of malignant tumours are not only dependent on alterations in the epithelial cell compartment, but are affected by their interaction with inflammatory cells and tumour-associated stroma. Studies in animal models have shown influence of tumour-associated macrophages (TAM on histological grade of differentiation in colon carcinoma. Disruption of transforming growth factor beta (TGF-beta signalling in tumour cells is related to more aggressive clinical behaviour. Expression data of components of this pathway in tumour-associated stroma is limited. Methods Tissue micro arrays of 310 colon carcinomas from curatively resected patients in UICC stage II and III were established. In a first step we quantified amount of CD68 positive TAMs and expression of components of TGF-beta signalling (TGF-beta1, TGF-beta receptors type 1 and 2, Smad 3 and 4 in tumour and associated stroma. Further we analyzed correlation to histological and clinical parameters (histological grade of differentiation (low-grade (i.e. grade 1 and 2 vs. high-grade (i.e. grade 3 and 4, lymph node metastasis, distant metastasis, 5 year cancer related survival using Chi-square or Fisher's exact test, when appropriate, to compare frequencies, Kaplan-Meier method to calculate 5-year rates of distant metastases and cancer-related survival and log rank test to compare the rates of distant metastases and survival. To identify independent prognostic factors Cox regression analysis including lymph node status and grading was performed. Results High-grade tumours and those with lymph node metastases showed higher rates of TAMs and lower expression of TGF-beta1. Loss of nuclear Smad4 expression in tumor was associated with presence of lymph node metastasis, but no influence on prognosis could be demonstrated. Decrease of both TGF-beta receptors in tumour-associated stroma was associated with increased lymph node metastasis and

  14. Effects of cigarette smoke exposure on nicotinic acetylcholine receptor subunits {alpha}7 and {beta}2 in the sudden infant death syndrome (SIDS) brainstem

    Energy Technology Data Exchange (ETDEWEB)

    Machaalani, Rita, E-mail: rita.machaalani@sydney.edu.au [Department of Medicine, The University of Sydney, NSW 2006 (Australia); Bosch Institute, The University of Sydney, NSW 2006 (Australia); The Children' s Hospital at Westmead, NSW 2145 (Australia); Say, Meichien [Department of Medicine, The University of Sydney, NSW 2006 (Australia); Bosch Institute, The University of Sydney, NSW 2006 (Australia); Waters, Karen A. [Department of Medicine, The University of Sydney, NSW 2006 (Australia); Bosch Institute, The University of Sydney, NSW 2006 (Australia); The Children' s Hospital at Westmead, NSW 2145 (Australia)

    2011-12-15

    It is postulated that nicotine, as the main neurotoxic constituent of cigarette smoke, influences SIDS risk through effects on nicotinic acetylcholine receptors (nAChRs) in brainstem nuclei that control respiration and arousal. This study compared {alpha}7 and {beta}2 nAChR subunit expression in eight nuclei of the caudal and rostral medulla and seven nuclei of the pons between SIDS (n = 46) and non-SIDS infants (n = 14). Evaluation for associations with known SIDS risk factors included comparison according to whether infants had a history of exposure to cigarette smoke in the home, and stratification for sleep position and gender. Compared to non-SIDS infants, SIDS infants had significantly decreased {alpha}7 in the caudal nucleus of the solitary tract (cNTS), gracile and cuneate nuclei, with decreased {beta}2 in the cNTS and increased {beta}2 in the facial. When considering only the SIDS cohort: 1-cigarette smoke exposure was associated with increased {alpha}7 in the vestibular nucleus and increased {beta}2 in the rostral dorsal motor nucleus of the vagus, rNTS and Cuneate, 2-there was a gender interaction for {alpha}7 in the gracile and cuneate, and {beta}2 in the cNTS and rostral arcuate nucleus, and 3-there was no effect of sleep position on {alpha}7, but prone sleep was associated with decreased {beta}2 in three nuclei of the pons. In conclusion, SIDS infants demonstrate differences in expression of {alpha}7 and {beta}2 nAChRs within brainstem nuclei that control respiration and arousal, which is independent on prior history of cigarette smoke exposure, especially for the NTS, with additional differences for smoke exposure ({beta}2), gender ({alpha}7 and {beta}2) and sleep position ({beta}2) evident. -- Highlights: Black-Right-Pointing-Pointer The 'normal' response to smoke exposure is decreased {alpha}7 and {beta}2 in certain nuclei. Black-Right-Pointing-Pointer SIDS infants have decreased {alpha}7 in cNTS, Grac and Cun. Black

  15. OXA-18, a class D clavulanic acid-inhibited extended-spectrum beta-lactamase from Pseudomonas aeruginosa.

    Science.gov (United States)

    Philippon, L N; Naas, T; Bouthors, A T; Barakett, V; Nordmann, P

    1997-01-01

    Clinical isolate Pseudomonas aeruginosa Mus showed resistance both to extended-spectrum cephalosporins and to aztreonam. We detected a typical double-disk synergy image when ceftazidime or aztreonam was placed next to a clavulanic acid disk on an agar plate. This resistance phenotype suggested the presence of an extended-spectrum beta-lactamase. Isoelectric focusing revealed that this strain produced three beta-lactamases, of pI 5.5, 7.4, and 8.2. A 2.6-kb Sau3A fragment encoding the extended-spectrum beta-lactamase of pI 5.5 was cloned from P. aeruginosa Mus genomic DNA. This enzyme, named OXA-18, had a relative molecular mass of 30.6 kDa. OXA-18 has a broad substrate profile, hydrolyzing amoxicillin, ticarcillin, cephalothin, ceftazidime, cefotaxime, and aztreonam, but not imipenem or cephamycins. Its activity was totally inhibited by clavulanic acid at 2 microg/ml. Hydrolysis constants of OXA-18 (Vmax, Km) confirmed the MIC results. Cloxacillin and oxacillin hydrolysis was noticeable with the partially purified OXA-18. The blaOXA-18 gene encodes a 275-amino-acid protein which has weak identity with all class D beta-lactamases except OXA-9 and OXA-12 (45 and 42% amino acid identity, respectively). OXA-18 is likely to be chromosomally encoded since no plasmid was found in the strain and because attempts to transfer the resistance marker failed. OXA-18 is peculiar since it is a class D beta-lactamase which confers high resistance to extended-spectrum cephalosporins and seems to have unique hydrolytic properties among non-class A enzymes. PMID:9333046

  16. Synthesis and pharmacological evaluation of 6-aminonicotinic acid analogues as novel γ-aminobutyric acidA receptor agonists

    DEFF Research Database (Denmark)

    Petersen, Jette Gellert; Sørensen, Troels Ersted; Damgaard, Maria;

    2014-01-01

    A series of 6-aminonicotinic acid analogues have been synthesized and pharmacologically characterized at native and selected recombinant GABAA receptors. 6-Aminonicotinic acid (3) as well as 2- and 4-alkylated analogues (9–11, 14–16) display low to mid-micromolar GABAAR binding affinities to nati...

  17. Brain activation by short-term nicotine exposure in anesthetized wild-type and beta2-nicotinic receptors knockout mice: a BOLD fMRI study

    Energy Technology Data Exchange (ETDEWEB)

    Suarez, S.V.; Changeux, J.P.; Granon, S. [Unite de Neurobiologie Integrative du Systeme Cholinergique, URA CNRS 2182, Institut Pasteur, Departement de Neuroscience, 25 rue du Dr Roux, 75015 Paris (France); Amadon, A.; Giacomini, E.; Le Bihan, D. [Service Hospitalier Frederic Joliot, 4 place du general Leclerc, 91400 Orsay (France); Wiklund, A. [Section of Anaesthesiology and Intensive Care Medicine, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm (Sweden)

    2009-07-01

    Rationale: The behavioral effects of nicotine and the role of the beta2-containing nicotinic receptors in these behaviors are well documented. However, the behaviors altered by nicotine rely on the functioning on multiple brain circuits where the high-affinity {beta}2-containing nicotinic receptors ({beta}2*nAChRs) are located. Objectives We intend to see which brain circuits are activated when nicotine is given in animals naive for nicotine and whether the {beta}2*nAChRs are needed for its activation of the blood oxygen level dependent (BOLD) signal in all brain areas. Materials and methods: We used functional magnetic resonance imaging (fMRI) to measure the brain activation evoked by nicotine (1 mg/kg delivered at a slow rate for 45 min) in anesthetized C57BL/6J mice and {beta}2 knockout (KO) mice. Results: Acute nicotine injection results in a significant increased activation in anterior frontal, motor, and somatosensory cortices and in the ventral tegmental area and the substantia nigra. Anesthetized mice receiving no nicotine injection exhibited a major decreased activation in all cortical and subcortical structures, likely due to prolonged anesthesia. At a global level, {beta}2 KO mice were not rescued from the globally declining BOLD signal. However, nicotine still activated regions of a meso-cortico-limbic circuit likely via {alpha}7 nicotinic receptors. Conclusions: Acute nicotine exposure compensates for the drop in brain activation due to anesthesia through the meso-cortico-limbic network via the action of nicotine on {beta}2*nAChRs. The developed fMRI method is suitable for comparing responses in wild-type and mutant mice. (authors)

  18. Liver X receptors alpha and beta regulate renin expression in vivo

    NARCIS (Netherlands)

    Morello, Fulvio; de Boer, Rudolf A; Steffensen, Knut R; Gnecchi, Massimiliano; Chisholm, Jeffrey W; Boomsma, Frans; Anderson, Leonard M; Lawn, Richard M; Gustafsson, Jan-Ake; Lopez-Ilasaca, Marco; Pratt, Richard E; Dzau, Victor J

    2005-01-01

    The renin-angiotensin-aldosterone system controls blood pressure and salt-volume homeostasis. Renin, which is the first enzymatic step of the cascade, is critically regulated at the transcriptional level. In the present study, we investigated the role of liver X receptor alpha (LXR(alpha)) and LXR(b

  19. Essential domain of receptor tyrosine phosphatase beta (RPTPbeta) for interaction with Helicobacter pylori vacuolating cytotoxin

    DEFF Research Database (Denmark)

    Yahiro, Kinnosuke; Wada, Akihiro; Yamasaki, Eiki;

    2004-01-01

    Helicobacter pylori produces a potent exotoxin, VacA, which causes progressive vacuolation as well as gastric injury. Although VacA was able to interact with two receptor-like protein tyrosine phosphatases, RPTPbeta and RPTPalpha, RPTPbeta was found to be responsible for gastric damage caused...

  20. Retinoic acid receptor gamma-induced misregulation of chondrogenesis in the murine limb bud in vitro.

    Science.gov (United States)

    Galdones, Eugene; Hales, Barbara F

    2008-11-01

    Vitamin A derivatives modulate gene expression through retinoic acid and rexinoid receptor (RAR/RXR) heterodimers and are indispensable for limb development. Of particular interest, RARgamma is highly expressed in cartilage, a target affected following retinoid-induced limb insult. The goal of this study was to examine how selective activation of RARgamma affects limb development. Forelimbs from E12.5 CD-1 mice were cultured for 6 days in the presence of all-trans RA (pan-RAR agonist; 0.1 or 1.0 microM) or BMS-189961 (BMS961, RARgamma-selective agonist; 0.01 or 0.1 microM) and limb morphology assessed. Untreated limbs developed normal cartilage elements whereas pan-RAR or RARgamma agonist-treated limbs exhibited reductive effects on chondrogenesis. Retinoid activity was assessed using RAREbeta2 (retinoic acid response element beta2)-lacZ reporter limbs; after 3 h of treatment, both drugs increased retinoid activity proximally. To elucidate the expression profiles of a subset of genes important for development, limbs were cultured for 3 h and cRNA hybridized to osteogenesis-focused microarrays. Two genes, matrix GLA protein (Mgp; chondrogenesis inhibitor) and growth differentiation factor-10 (Gdf10/Bmp3b) were induced by RA and BMS-189961. Real-time PCR was done to validate our results and whole mount in situ hybridizations against Mgp and Gdf10 localized their upregulation to areas of cartilage and programmed cell death, respectively. Thus, our results illustrate the importance of RARgamma in mediating the retinoid-induced upregulation of Mgp and Gdf10; determining their roles in chondrogenesis and cell death will help further unravel mechanisms underlying retinoid teratogenicity. PMID:18703560

  1. Interaction between retinoid acid receptor-related orphan receptor alpha (RORA and neuropeptide S receptor 1 (NPSR1 in asthma.

    Directory of Open Access Journals (Sweden)

    Nathalie Acevedo

    Full Text Available Retinoid acid receptor-related Orphan Receptor Alpha (RORA was recently identified as a susceptibility gene for asthma in a genome-wide association study. To investigate the impact of RORA on asthma susceptibility, we performed a genetic association study between RORA single nucleotide polymorphisms (SNPs in the vicinity of the asthma-associated SNP (rs11071559 and asthma-related traits. Because the regulatory region of a previously implicated asthma susceptibility gene, Neuropeptide S receptor 1 (NPSR1, has predicted elements for RORA binding, we hypothesized that RORA may interact biologically and genetically with NPSR1. 37 RORA SNPs and eight NPSR1 SNPs were genotyped in the Swedish birth cohort BAMSE (2033 children and the European cross-sectional PARSIFAL study (1120 children. Seven RORA SNPs confined into a 49 kb region were significantly associated with physician-diagnosed childhood asthma. The most significant association with rs7164773 (T/C was driven by the CC genotype in asthma cases (OR = 2.0, 95%CI 1.36-2.93, p = 0.0003 in BAMSE; and 1.61, 1.18-2.19, p = 0.002 in the combined BAMSE-PARSIFAL datasets, respectively, and strikingly, the risk effect was dependent on the Gln344Arg mutation in NPSR1. In cell models, stimulation of NPSR1 activated a pathway including RORA and other circadian clock genes. Over-expression of RORA decreased NPSR1 promoter activity further suggesting a regulatory loop between these genes. In addition, Rora mRNA expression was lower in the lung tissue of Npsr1 deficient mice compared to wildtype littermates during the early hours of the light period. We conclude that RORA SNPs are associated with childhood asthma and show epistasis with NPSR1, and the interaction between RORA and NPSR1 may be of biological relevance. Combinations of common susceptibility alleles and less common functional polymorphisms may modify the joint risk effects on asthma susceptibility.

  2. Interaction of Protease-Activated Receptor 2 with G Proteins and Beta-Arrestin 1 Studied by Bioluminescence Resonance Energy Transfer

    Directory of Open Access Journals (Sweden)

    Mohammed Akli eAyoub

    2013-12-01

    Full Text Available G protein-coupled receptors (GPCRs are well recognized as being able to activate several signaling pathways through the activation of different G proteins as well as other signaling proteins such as beta-arrestins. Therefore, understanding how such multiple GPCR-mediated signaling can be integrated constitute an important aspect. Here, we applied bioluminescence resonance energy transfer (BRET to shed more light on the G protein coupling profile of trypsin receptor, or protease-activated receptor 2 (PAR2, and its interaction with beta-arrestin1. Using YFP and Rluc fusion constructs expressed in COS-7 cells, BRET data revealed a pre-assembly of PAR2 with both Galphai1 and Galphao and a rapid and transient activation of these G proteins upon receptor activation. In contrast, no preassembly of PAR2 with Galpha12 could be detected and their physical association can be measured with a very slow and sustained kinetics similar to that of beta-arrestin1 recruitment. These data demonstrate the coupling of PAR2 with Galphai1, Galphao and Galpha12 in COS-7 cells with differences in the kinetics of GPCR-G protein coupling, a parameter that very likely influences the cellular response. Moreover, this further illustrates that preassembly or agonist-induced G protein interaction depends on receptor-G protein pairs indicating another level of complexity and regulation of the signaling of GPCR-G protein complexes and its multiplicity.

  3. Computational Studies of Beta Amyloid (Aβ42 with p75NTR Receptor: A Novel Therapeutic Target in Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    Shine Devarajan

    2014-01-01

    Full Text Available Alzheimer’s disease is a neurodegenerative disorder characterized by the accumulation of beta amyloid plaques (Aβ which can induce neurite degeneration and progressive dementia. It has been identified that neuronal apoptosis is induced by binding of Aβ42 to pan neurotrophin receptor (p75NTR and gave the possibility that beta amyloid oligomer is a ligand for p75NTR. However, the atomic contact point responsible for molecular interactions and conformational changes of the protein upon binding was not studied in detail. In view of this, we conducted a molecular docking and simulation study to investigate the binding behaviour of Aβ42 monomer with p75NTR ectodomain. Furthermore, we proposed a p75NTR-ectodomain-Aβ42 complex model. Our data revealed that, Aβ42 specifically recognizes CRD1 and CRD2 domains of the receptor and formed a “cap” like structure at the N-terminal of receptor which is stabilized by a network of hydrogen bonds. These findings are supported by molecular dynamics simulation that Aβ42 showed distinct structural alterations at N- and C-terminal regions due to the influence of the receptor binding site. Overall, the present study gives more structural insight on the molecular interactions of beta amyloid protein involved in the activation of p75NTR receptor.

  4. Developmental Changes is Expression of Beta-Adrenergic Receptors in Cultures of C2C12 Skeletal Muscle Cells

    Science.gov (United States)

    Young, Ronald B.; Bridge, K. Y.; Vaughn, J. R.

    2000-01-01

    beta-Adrenergic receptor (bAR) agonists have been reported to modulate growth in several mammalian and avian species, and bAR agonists presumably exert their physiological action on skeletal muscle cells through this receptor. Because of the importance of bAR regulation on muscle protein metabolism in muscle cells, the objectives of this study were to determine the developmental expression pattern of the bAR population in C2C12 skeletal muscle cells, and to analyze changes in both the quantity and isoform expression of the major muscle protein, myosin. The number of bAR in mononucleated C2C12 cells was approximately 8,000 bAR per cell, which is comparable with the population reported in several other nonmuscle cell types. However, the bar population increased after myoblast fusion to greater than 50,000 bAR per muscle cell equivalent. The reasons for this apparent over-expression of bAR in C2C12 cells is not known. The quantity of myosin also increased after C2C12 myoblast fusion, but the quantity of myosin was less than that reported in primary muscle cell cultures. Finally, at least five different isoforms of myosin heavy chain could be resolved in C2C12 cells, and three of these exhibited either increased or decreased developmental regulation relative to the others. Thus, C2C12 myoblasts undergo developmental regulation of bAR population and myosin heavy chain isoform expression.

  5. Gut-homing CD4+ T cell receptor alpha beta+ T cells in the pathogenesis of murine inflammatory bowel disease

    DEFF Research Database (Denmark)

    Rudolphi, A; Boll, G; Poulsen, S S;

    1994-01-01

    We studied which T cell subsets from the gut-associated lymphoid tissue (GALT) can migrate out of the gut mucosa and repopulate GALT compartments of an immunodeficient (semi)syngeneic host. Many distinct lymphocyte subsets were found in GALT of immunocompetent H-2d (BALB/c, BALB/cdm2, C.B-17......+/+) mice. No antigen receptor-expressing lymphoid cells were found in GALT of congenic C.B-17 scid/scid (scid) mice. The heterotopic transplantation of a full-thickness gut wall graft from the ileum or colon of immunocompetent (C.B-17+/+, BALB/cdm2) donor mice onto immunodeficient scid mice selectively...... reconstituted a CD3+ T cell receptor alpha beta+ CD4+ T cell subset. CD4+ cells of this subset expressed the surface phenotype of mucosa-seeking, memory T cells. In the immunodeficient scid host, this gut-derived CD4+ T cell subset was found in spleen, peritoneal cavity, mesenteric lymph nodes (LN), epithelial...

  6. Targeted correction of a thalassemia-associated beta-globin mutation induced by pseudo-complementary peptide nucleic acids

    DEFF Research Database (Denmark)

    Lonkar, Pallavi; Kim, Ki-Hyun; Kuan, Jean Y;

    2009-01-01

    Beta-thalassemia is a genetic disorder caused by mutations in the beta-globin gene. Triplex-forming oligonucleotides and triplex-forming peptide nucleic acids (PNAs) have been shown to stimulate recombination in mammalian cells via site-specific binding and creation of altered helical structures...... that provoke DNA repair. However, the use of these molecules for gene targeting requires homopurine tracts to facilitate triple helix formation. Alternatively, to achieve binding to mixed-sequence target sites for the induced gene correction, we have used pseudo-complementary PNAs (pcPNAs). Due to steric...... hindrance, pcPNAs are unable to form pcPNA-pcPNA duplexes but can bind to complementary DNA sequences via double duplex-invasion complexes. We demonstrate here that pcPNAs, when co-transfected with donor DNA fragments, can promote single base pair modification at the start of the second intron of the beta...

  7. Radiation synthesis of pH-sensitive hydrogels from {beta}-cyclodextrin-grafted PEG and acrylic acid for drug delivery

    Energy Technology Data Exchange (ETDEWEB)

    Chen Jie; Rong Liang [Department of Chemical Engineering and Technology, School of Environmental and Chemical Engineering, Shanghai University, Baoshan, Shanghai 200444 (China); Lin Han, E-mail: linhan1205@yahoo.com.cn [Department of Chemical Engineering and Technology, School of Environmental and Chemical Engineering, Shanghai University, Baoshan, Shanghai 200444 (China); Xiao Ruijia; Wu Huifeng [Department of Chemical Engineering and Technology, School of Environmental and Chemical Engineering, Shanghai University, Baoshan, Shanghai 200444 (China)

    2009-07-15

    A water-soluble macromonomer (PEG-{beta}-CD) was synthesised by reaction of {beta}-cyclodextrin with poly(ethylene glycol) diglycidyl ether. Then, a novel hydrogel with pH-sensitivity was prepared by irradiating the mixture of acrylic acid and PEG-{beta}-CD with electron beam. Compared with the normal PAAc hydrogel, this novel hydrogel had a higher swelling ratio at pH 3-8. 5-Fluorouracil (5-FU) was chosen as a model drug, and the kinetics of 5-FU releasing behavior was studied. Compared with the PAAc hydrogel, the results showed the release time of 5-FU from the cyclodextrin containing hydrogel was prolonged. It may be ascribed to the formation of inclusion complexes between the drug molecules and cyclodextrin groups.

  8. Deletion of angiotensin II type 2 receptor accelerates adipogenesis in murine mesenchymal stem cells via Wnt10b/beta-catenin signaling.

    Science.gov (United States)

    Matsushita, Kenichi; Wu, Yaojiong; Pratt, Richard E; Dzau, Victor J

    2016-08-01

    Recent evidence suggests that the renin-angiotensin system (RAS) has a vital role in adipocyte biology and the pathophysiology of metabolic syndrome. Obesity is the main culprit of metabolic syndrome; and mesenchymal stem cells (MSCs) have been forwarded as a major source of adipocyte generation. Previously, we reported that MSCs have a local RAS and that pharmacological blockade of angiotensin II type 2 receptor (AT2R) promotes adipogenesis in human MSCs. However, the definitive roles of AT2R and how AT2R functions in adipogenesis remains unknown. To this end, we employed AT2R-null murine MSCs to characterize how AT2R affects the differentiation of MSCs into adipocytes. Murine MSCs were isolated from AT2R-null mice and wild-type littermates, grown to confluency, and then differentiated into adipocytes. Adipogenesis was quantitated by assessing the lipid droplet accumulation. Using the lipophilic fluorescent dye, the AT2R-null cells showed significantly increased total fluorescence (261.6±49.6% vs littermate) on day 7. Oil red O staining followed by extraction of the absorbed dye and measurement of the absorbance on day 14 also exhibited significantly increased lipid droplet accumulation in the AT2R-null cells (202.7±14.1% vs littermate). We also examined the expression of adipogenic marker genes by quantitative RT-PCR. The AT2R-null group exhibited significantly increased expression of PPAR-gamma, fatty acid synthase, and adiponectin (vs littermate). We further examined the role of Wnt10b/beta-catenin signaling, which reportedly has an important inhibitory role in adipogenesis. The AT2R-null group exhibited significantly decreased Wnt10b expression accompanied by decreased beta-catenin (vs littermate). Our results thus revealed that the AT2R inhibits adipogenic differentiation in murine MSCs. Moreover, this inhibitory effect is associated with Wnt10b/beta-catenin signaling. These results provide important insights into the pathophysiology of obesity and obesity

  9. Data for amino acid alignment of Japanese stingray melanocortin receptors with other gnathostome melanocortin receptor sequences, and the ligand selectivity of Japanese stingray melanocortin receptors

    Directory of Open Access Journals (Sweden)

    Akiyoshi Takahashi

    2016-06-01

    Full Text Available This article contains structure and pharmacological characteristics of melanocortin receptors (MCRs related to research published in “Characterization of melanocortin receptors from stingray Dasyatis akajei, a cartilaginous fish” (Takahashi et al., 2016 [1]. The amino acid sequences of the stingray, D. akajei, MC1R, MC2R, MC3R, MC4R, and MC5R were aligned with the corresponding melanocortin receptor sequences from the elephant shark, Callorhinchus milii, the dogfish, Squalus acanthias, the goldfish, Carassius auratus, and the mouse, Mus musculus. These alignments provide the basis for phylogenetic analysis of these gnathostome melanocortin receptor sequences. In addition, the Japanese stingray melanocortin receptors were separately expressed in Chinese Hamster Ovary cells, and stimulated with stingray ACTH, α-MSH, β-MSH, γ-MSH, δ-MSH, and β-endorphin. The dose response curves reveal the order of ligand selectivity for each stingray MCR.

  10. The glucocorticoid properties of the synthetic steroid pregna-1,4-diene-11beta-ol-3,20-dione (deltaHOP) are not entirely correlated with the steroid binding to the glucocorticoid receptor.

    Science.gov (United States)

    Vicent, G P; Pecci, A; Ghini, A A; Piwien-Pilipuk, G; Veleiro, A S; Burton, G; Lantos, C P; Galigniana, M D

    1999-03-25

    The natural steroid 11beta-hydroxyprogesterone is not only a modulator of 11beta-hydroxy-steroid dehydrogenase activity, but also an efficient inducer of tyrosine aminotransferase activity in hepatocytes. In contrast with the low affinity for the mineralocorticoid receptor. 11beta-hydroxyprogesterone binds well to both the glucocorticoid receptor and the carrier protein transcortin. It is accepted that the introduction of a 1:ene double bond into 3-keto 4:ene steroids increases the glucocorticoid potency, so that 3-keto-1,4:diene steroids show improved chemical stability and are more potent glucocorticoids than their respective 4:ene analogs. The steroid pregna-1,4-diene-11beta-ol-3,20-dione (deltaHOP) had previously been described as an anti-inflamatory compound and an inhibitor of macromolecular biosynthesis in thymocytes and lymphocytes. In such studies, deltaHOP also exhibited some particular glucocorticoid properties which made it attractive as a tool for the study of the mechanism of action of glucocorticoids. In the present paper we show that deltaHOP possesses some classical biological actions of glucocorticoids such as deposition of glycogen in rat liver, induction of TAT activity in hepatocytes, and inhibition of the uptake of leucine and thymidine by thymocytes. It also exhibits minimal sodium-retaining properties. Consistent with these biological effects, deltaHOP shows a 70 times lower relative binding affinity for the mineralocortioid receptor than aldosterone, but a reasonable affinity for the glucocorticoid receptor, and is as efficient as dexamethasone in dissociating the 90 kDa heat shock protein from the glucocorticoid receptor heterocomplex. However, the inhibition of the uptake of amino acids and nucleotides observed in the presence of deltaHOP is not efficiently blocked when thymocytes are coincubated in the presence of steroids with known antiglucocorticoid activity. deltaHOP is similarly inefficient in inducing chloramphenicol

  11. Triphenyl phosphate-induced developmental toxicity in zebrafish: Potential role of the retinoic acid receptor

    OpenAIRE

    Isales, Gregory M.; Hipszer, Rachel A.; Tara D Raftery; Chen, Albert; Stapleton, Heather M.; Volz, David C.

    2015-01-01

    Using zebrafish as a model, we previously reported that developmental exposure to triphenyl phosphate (TPP) – a high-production volume organophosphate-based flame retardant – results in dioxin-like cardiac looping impairments that are independent of the aryl hydrocarbon receptor. Using a pharmacologic approach, the objective of this study was to investigate the potential role of retinoic acid receptor (RAR) – a nuclear receptor that regulates vertebrate heart morphogenesis – in mediating TPP-...

  12. The effects of beta acids from hops (Humulus lupulus) on mortality of Varroa destructor (Acari: Varroidae).

    Science.gov (United States)

    Degrandi-Hoffman, Gloria; Ahumada, Fabiana; Probasco, Gene; Schantz, Lloyd

    2012-12-01

    Hop (Humulus lupulus L.) beta acids (HBA) were tested for miticidal effects on varroa destructor Anderson and Trueman, a parasitic mite of the honey bee (Apis mellifera L.). When varroa were placed on bees that had topical applications of 1 % HBA, there was 100 % mite mortality. Bee mortality was unaffected. Cardboard strips saturated with HBA and placed in colonies resulted in mite drop that was significantly greater than in untreated hives. HBA was detected on about 60 % of the bees in colonies during the first 48 h after application. Mite drop in colonies lasted for about 7 days with the highest drop occurring in the first 2-3 days after treatment. There was a reduction in the percentages of bees with HBA and in the amounts on their bodies after 7 days. Bee and queen mortality in the colonies were not affected by HBA treatments. When cardboard strips saturated with HBA were put in packages of bees, more than 90 % of the mites were killed without an increase in bee mortality. HBA might have potential to control varroa when establishing colonies from packages or during broodless periods.

  13. Crystallochemical study of amides derived from 6{alpha}, 7{beta}-diidroxivoacapan-17{beta}-oic acid by X-ray diffraction; Estudo cristaloquimico de amidas derivadas do acido 6{alpha}, 7{beta}-di- hidroxivouacapan-17 {beta}-oico por difracao de raios-X

    Energy Technology Data Exchange (ETDEWEB)

    Branco, Marcello Cardoso; Prado Gambardella, Maria Teresa do [Sao Paulo Univ., Sao Carlos, SP (Brazil). Inst. de Quimica. Dept. de Quimica e Fisica Molecular

    1995-12-31

    Abstract. The 6{alpha}, 7{beta}-diidroxivoacapan-17{beta}-oic acid (DVA) is a Furane-diterpene isolated from Peterodon genus. It has anti inflammatory and analgesic properties. The purpose of this work is the characterization of amides derived from DVA, in order to understand the relationship between Chemical Structure and Biological Activity of Vouacapanes. The structures of DVA derivatives will be solved by single-crystal X-ray diffraction. (author) 15 refs., 2 figs.

  14. Crystallochemical study of esters derived from 6{alpha}, 7{beta}-diidroxivouacapan-17{beta}-oic acid by x-ray diffraction; Estudo cristaloquimico de esteres derivados do acido 6{alpha}, 6{beta}-di-hidroxivouacapan-17{beta}-oico por difracao de raios-X

    Energy Technology Data Exchange (ETDEWEB)

    Abrahao Junior, Odonirio [Sao Paulo Univ., Sao Carlos, SP (Brazil). Inst. de Quimica

    1995-12-31

    The 6{alpha}, 7{beta}-diidroxivoacapan-17{beta}-oic acid (DVA) is a Furane-diterpene isolated from Peterodon genus. It has anti-inflammatory and analgesic properties. The purpose of this work is the characterisation by x-ray single crystal diffraction technique of esters derived from DVA, to understand the relationship between chemical structure and biological activity of vouacapanes. (author) 15 refs.

  15. Prediction of selective estrogen receptor beta agonist using open data and machine learning approach

    OpenAIRE

    Niu,Ai-qin; Xie, Liang-jun; Wang, Hui; Bing ZHU; Wang, Sheng-Qi

    2016-01-01

    Background Estrogen receptors (ERs) are nuclear transcription factors that are involved in the regulation of many complex physiological processes in humans. ERs have been validated as important drug targets for the treatment of various diseases, including breast cancer, ovarian cancer, osteoporosis, and cardiovascular disease. ERs have two subtypes, ER-α and ER-β. Emerging data suggest that the development of subtype-selective ligands that specifically target ER-β could be a more optimal appr...

  16. Receptor Density Is Key to the Alpha2/Beta Interferon Differential Activities

    OpenAIRE

    Moraga, I.; Harari, D.; Schreiber, G.; Uze, G.; Pellegrini, S.

    2009-01-01

    Multiple type I interferons (IFN-α/β) elicit Jak/Stat activation, rapid gene induction, and pleiotropic effects, such as differentiation, antiviral protection, and blocks in proliferation, which are dependent on the IFN subtype and the cellular context. To date, ligand- and receptor-specific molecular determinants underlying IFN-α/β differential activities or potencies have been well characterized. To analyze cellular determinants that impact subtype-specific potency, human fibrosarcoma U5A-d...

  17. The evolving role of oestrogen receptor beta in clinical breast cancer

    OpenAIRE

    Speirs, Valerie

    2008-01-01

    Controversy surrounds the potential clinical importance of oestrogen receptor (ER)β in breast cancer, and three recent papers have sought to resolve this. In the present issue of Breast Cancer Research Novelli and colleagues explored the significance of ERβ1 expression in 936 breast cancer patients, and they showed diverse relationships according to lymph node status. A second paper examined 442 breast cancers in which ERβ1 was an independent predictor of recurrence, disease-free survival and...

  18. Novel 3-carboxy- and 3-phosphonopyrazoline amino acids as potent and selective NMDA receptor antagonists

    DEFF Research Database (Denmark)

    Conti, Paola; Pinto, Andrea; Tamborini, Lucia;

    2010-01-01

    The design and synthesis of new N1-substituted 3-carboxy- and 3-phosphonopyrazoline and pyrazole amino acids that target the glutamate binding site of NMDA receptors are described. An analysis of the stereochemical requirements for high-affinity interaction with these receptors was performed. We ...

  19. Interleukin 1 receptor antagonist mediates the beneficial effects of systemic interferon beta in mice: implications for rheumatoid arthritis

    NARCIS (Netherlands)

    M. Corr; D.L. Boyle; L.M. Ronacher; B.R. Lew; L.G. van Baarsen; P.P. Tak; G.S. Firestein

    2011-01-01

    Objectives Interferon beta (IFN beta) therapy is effective in multiple sclerosis and murine models of arthritis. Surprisingly, systemic IFN beta treatment induces only minimal improvement in rheumatoid arthritis (RA). To explain this paradox, the authors evaluated the mechanism of IFN beta benefit i

  20. Potentiation of gamma aminobutyric acid receptors (GABAAR by Ethanol: How are inhibitory receptors affected?

    Directory of Open Access Journals (Sweden)

    Benjamin eFörstera

    2016-05-01

    Full Text Available In recent years there has been an increase in the understanding of ethanol actions on the type A -aminobutyric acid chloride channel (GABAAR, a member of the pentameric ligand gated ion channels (pLGICs. However, the mechanism by which ethanol potentiates the complex is still not fully understood and a number of publications have shown contradictory results. Thus many questions still remain unresolved requiring further studies for a better comprehension of this effect. The present review concentrates on the involvement of GABAAR in the acute actions of ethanol and specifically focuses on the immediate, direct or indirect, synaptic and extra-synaptic modulatory effects. To elaborate on the immediate, direct modulation of GABAAR by acute ethanol exposure, electrophysiological studies investigating the importance of different subunits, and data from receptor mutants will be examined. We will also discuss the nature of the putative binding sites for ethanol based on structural data obtained from other members of the pLGICs family. Finally, we will briefly highlight the glycine gated chloride channel (GlyR, another member of the pLGIC family, as a suitable target for the development of new pharmacological tools.

  1. The fatty acid beta-oxidation pathway is important for decidualization of endometrial stromal cells in both humans and mice.

    Science.gov (United States)

    Tsai, Jui-He; Chi, Maggie M-Y; Schulte, Maureen B; Moley, Kelle H

    2014-02-01

    Embryo implantation and development requires the endometrial stromal cells (ESCs) to undergo decidualization. This differentiation process requires glucose utilization, and blockade of the pentose phosphate pathway inhibits decidualization of ESCs both in vitro and in vivo. Glucose and fatty acids are energy substrates for many cell types, and fatty acid beta-oxidation is critical for embryo implantation. Here, we investigated whether beta-oxidation is required for decidualization of ESCs. As assessed by marker gene expression, decidualization of human primary ESCs was blocked by reducing activity of carnitine calmitoyltransferase I, the rate-limiting enzyme in beta-oxidation, either by short hairpin RNA-mediated silencing or by treatment with the inhibitor etomoxir. Ranolazine (RAN), a partial beta-oxidation inhibitor, blocked early decidualization of a human ESC line. However, decidualization resumed after several days, most likely due to a compensatory up-regulation of GLUT1 expression and an increase in glucose metabolism. Simultaneous inhibition of the beta-oxidation pathway with RAN and the pentose phosphate pathway with glucosamine (GlcN) impaired in vitro decidualization of human ESCs more strongly than inhibition of either pathway alone. These findings were confirmed in murine ESCs in vitro, and exposure to RAN plus GlcN inhibited decidualization in vivo in a deciduoma model. Finally, intrauterine implantation of time-release RAN and GlcN pellets reduced pup number. Importantly, pup number returned to normal after the end of the pellet-active period. This work indicates that both fatty acids and glucose metabolism pathways are important for ESC decidualization, and suggests novel pathways to target for the design of future nonhormonal contraceptives.

  2. Mapping of the {alpha}{sub 4} subunit gene (GABRA4) to human chromosome 4 defines an {alpha}{sub 2}-{alpha}{sub 4}-{beta}{sub 1}-{gamma}{sub 1} gene cluster: Further evidence that modern GABA{sub a} receptor gene clusters are derived from an ancestral cluster

    Energy Technology Data Exchange (ETDEWEB)

    McLean, P.J.; Farb, D.H.; Russek, S.J. [Boston Univ. School of Medicine, MA (United States)] [and others

    1995-04-10

    We demonstrated previously that an {alpha}{sub 1}-{beta}{sub 2}-{gamma}{sub 2} gene cluster of the {gamma}-aminobutyric acid (GABA{sub A}) receptor is located on human chromosome 5q34-q35 and that an ancestral {alpha}-{beta}-{gamma} gene cluster probably spawned clusters on chromosomes 4, 5, and 15. Here, we report that the {alpha}{sub 4} gene (GABRA4) maps to human chromosome 4p14-q12, defining a cluster comprising the {alpha}{sub 2}, {alpha}{sub 4}, {beta}{sub 1}, and {gamma}{sub 1} genes. The existence of an {alpha}{sub 2}-{alpha}{sub 4}-{beta}{sub 1}-{gamma}{sub 2} cluster on chromosome 4 and an {alpha}{sub 1}-{alpha}{sub 6}-{beta}{sub 2}-{gamma}{sub 2} cluster on chromosome 5 provides further evidence that the number of ancestral GABA{sub A} receptor subunit genes has been expanded by duplication within an ancestral gene cluster. Moreover, if duplication of the {alpha} gene occurred before duplication of the ancestral gene cluster, then a heretofore undiscovered subtype of a subunit should be located on human chromosome 15q11-q13 within an {alpha}{sub 5}-{alpha}{sub x}-{beta}{sub 3}-{gamma}{sub 3} gene cluster at the locus for Angelman and Prader-Willi syndromes. 34 refs., 6 figs., 1 tab.

  3. Modeling the interactions of a peptide-major histocompatibility class I ligand with its receptors. II. Cross-reaction between a monoclonal antibody and two alpha beta T cell receptors

    DEFF Research Database (Denmark)

    Rognan, D; Engberg, J; Stryhn, A;

    2000-01-01

    -peptide pair into the Fab combining site. Interestingly, the most energetically favored binding mode shows numerous analogies to the recently determined recognition of class I MHC-peptide complexes by alpha beta T cell receptors (TCRs). The pSAN13.4.1 also binds diagonally across the MHC binding groove...

  4. Nicotinic acid receptor abnormalities in human skin cancer: implications for a role in epidermal differentiation.

    Directory of Open Access Journals (Sweden)

    Yira Bermudez

    Full Text Available BACKGROUND: Chronic UV skin exposure leads to epidermal differentiation defects in humans that can be largely restored by pharmacological doses of nicotinic acid. Nicotinic acid has been identified as a ligand for the human G-protein-coupled receptors GPR109A and GPR109B that signal through G(i-mediated inhibition of adenylyl cyclase. We have examined the expression, cellular distribution, and functionality of GPR109A/B in human skin and skin derived epidermal cells. RESULTS: Nicotinic acid increases epidermal differentiation in photodamaged human skin as judged by the terminal differentiation markers caspase 14 and filaggrin. Both GPR109A and GPR109B genes are transcribed in human skin and in epidermal keratinocytes, but expression in dermal fibroblasts is below limits of detection. Receptor transcripts are greatly over-expressed in squamous cell cancers. Receptor protein in normal skin is prominent from the basal through granular layers of the epidermis, with cellular localization more dispersive in the basal layer but predominantly localized at the plasma membrane in more differentiated epidermal layers. In normal human primary and immortalized keratinocytes, nicotinic acid receptors show plasma membrane localization and functional G(i-mediated signaling. In contrast, in a squamous cell carcinoma derived cell line, receptor protein shows a more diffuse cellular localization and the receptors are nearly non-functional. CONCLUSIONS: The results of these studies justify future genetic and pharmacological intervention studies to define possible specific role(s of nicotinic acid receptors in human skin homeostasis.

  5. Interactions between Human Liver Fatty Acid Binding Protein and Peroxisome Proliferator Activated Receptor Selective Drugs

    OpenAIRE

    Tony Velkov

    2013-01-01

    Fatty acid binding proteins (FABPs) act as intracellular shuttles for fatty acids as well as lipophilic xenobiotics to the nucleus, where these ligands are released to a group of nuclear receptors called the peroxisome proliferator activated receptors (PPARs). PPAR mediated gene activation is ultimately involved in maintenance of cellular homeostasis through the transcriptional regulation of metabolic enzymes and transporters that target the activating ligand. Here we show that liver- (L-) FA...

  6. Castor oil induces laxation and uterus contraction via ricinoleic acid activating prostaglandin EP3 receptors

    OpenAIRE

    Tunaru, Sorin; Althoff, Till F.; Nüsing, Rolf M.; Diener, Martin; Offermanns, Stefan

    2012-01-01

    Castor oil is one of the oldest drugs. When given orally, it has a laxative effect and induces labor in pregnant females. The effects of castor oil are mediated by ricinoleic acid, a hydroxylated fatty acid released from castor oil by intestinal lipases. Despite the wide-spread use of castor oil in conventional and folk medicine, the molecular mechanism by which ricinoleic acid acts remains unknown. Here we show that the EP3 prostanoid receptor is specifically activated by ricinoleic acid and...

  7. Castor oil induces laxation and uterus contraction via ricinoleic acid activating prostaglandin EP3 receptors.

    Science.gov (United States)

    Tunaru, Sorin; Althoff, Till F; Nüsing, Rolf M; Diener, Martin; Offermanns, Stefan

    2012-06-01

    Castor oil is one of the oldest drugs. When given orally, it has a laxative effect and induces labor in pregnant females. The effects of castor oil are mediated by ricinoleic acid, a hydroxylated fatty acid released from castor oil by intestinal lipases. Despite the wide-spread use of castor oil in conventional and folk medicine, the molecular mechanism by which ricinoleic acid acts remains unknown. Here we show that the EP(3) prostanoid receptor is specifically activated by ricinoleic acid and that it mediates the pharmacological effects of castor oil. In mice lacking EP(3) receptors, the laxative effect and the uterus contraction induced via ricinoleic acid are absent. Although a conditional deletion of the EP(3) receptor gene in intestinal epithelial cells did not affect castor oil-induced diarrhea, mice lacking EP(3) receptors only in smooth-muscle cells were unresponsive to this drug. Thus, the castor oil metabolite ricinoleic acid activates intestinal and uterine smooth-muscle cells via EP(3) prostanoid receptors. These findings identify the cellular and molecular mechanism underlying the pharmacological effects of castor oil and indicate a role of the EP(3) receptor as a target to induce laxative effects.

  8. Deorphanization of GPRC6A: a promiscuous L-alpha-amino acid receptor with preference for basic amino acids

    DEFF Research Database (Denmark)

    Wellendorph, Petrine; Hansen, Kasper B; Balsgaard, Anders;

    2005-01-01

    and was employed to rationally select potential ligands. Measurement of Ca2+-dependent chloride currents in Xenopus laevis oocytes facilitated the deorphanization of h6A/5.24 and identification of L-alpha-amino acids as agonists. The most active agonists were basic L-alpha-amino acids, L-Arg, L-Lys, and L......One of the most important tasks of molecular pharmacology is the deorphanization of the large number of G-protein-coupled receptors with unidentified endogenous agonists. We recently reported the cloning and analysis of expression of a novel human family C G-protein-coupled receptor, termed hGPRC6A....... To identify agonists at this orphan receptor, we faced the challenges of achieving surface expression in mammalian cell lines and establishing an appropriate functional assay. Generating a chimeric receptor construct, h6A/5.24, containing the ligand binding amino-terminal domain (ATD) of hGPRC6A...

  9. Correction of a splice-site mutation in the beta-globin gene stimulated by triplex-forming peptide nucleic acids

    OpenAIRE

    Chin, Joanna Y; Kuan, Jean Y.; Lonkar, Pallavi S.; Krause, Diane S.; Seidman, Michael M.; Peterson, Kenneth R.; Nielsen, Peter E.; Kole, Ryszard; Glazer, Peter M.

    2008-01-01

    Splice-site mutations in the beta-globin gene can lead to aberrant transcripts and decreased functional beta-globin, causing beta-thalassemia. Triplex-forming DNA oligonucleotides (TFOs) and peptide nucleic acids (PNAs) have been shown to stimulate recombination in reporter gene loci in mammalian cells via site-specific binding and creation of altered helical structures that provoke DNA repair. We have designed a series of triplex-forming PNAs that can specifically bind to sequences in the hu...

  10. Interleukin-1-mediated febrile responses in mice and interleukin-1 beta activation of NFkappaB in mouse primary astrocytes, involves the interleukin-1 receptor accessory protein.

    Science.gov (United States)

    Zetterström, M; Lundkvist, J; Malinowsky, D; Eriksson, G; Bartfai, T

    1998-06-01

    The endogenous pyrogen interleukin-1 (IL-1) is considered as one of the key molecules in orchestrating the host response of injury and inflammation. IL-1 exerts its effects upon binding to the type I IL-1 receptor (IL-1RI). The IL-1-IL-1RI complex is further thought to associate with the IL-1 receptor accessory protein (IL-1RAcP), which is suggested to be important for most IL-1 signal transduction pathways. With the aim of investigating the importance of the IL-1RAcP in IL-1 signalling, IL-1alpha and IL-1beta induced febrile responses and IL-1beta-mediated activation of NFkappaB in primary astrocyte cultures were examined using IL-1RAcP-deficient (IL-1RAcP KO) and wild type mice, respectively. It was shown that neither recombinant rat IL-1alpha (rrIL-1alpha, 25 microg/kg), recombinant rat IL-1beta (rrIL-1beta, 40 microg/kg) nor recombinant human IL-1beta (rhIL-1beta, 50 microg/kg) injected i.p. could elicit febrile responses in the IL-1RAcP-deficient mice, while the same doses of rrIL-1alpha/beta or rhIL-1beta injected into wild type mice caused normal fever responses. A febrile response could be induced in the IL-1RAcP-deficient mice by i.p. administration of E. coli lipopolysaccharide (LPS, 50 microg/kg) and this response was similar to that obtained in wild type mice. Furthermore, it was shown that rhIL-1beta activated, in a concentration-dependent manner, nuclear translocation of the transcriptional nuclear factor kappa B (NFkappaB) in primary astrocyte cultures prepared from wild type mice, whereas no IL-1beta-induced translocation of NFkappaB could be detected in cultures prepared from IL-1RAcP-deficient mice, as revealed by electrophoretic mobility shift assay (EMSA). The rhIL-1beta-induced NFkappaB complexes were shown to contain p50 but no, or very little, p65 and cRel immunoreactive proteins.

  11. Inactivation of lambda phage infectivity and lambda deoxyribonucleic acid transfection by N-methyl-isatin beta-thiosemicarbazone-copper complexes.

    Science.gov (United States)

    Levinson, W; Helling, R

    1976-01-01

    The infectivity of intact lambda phage and transfection by lambda deoxyribonucleic acid were inactivated by exposure to the copper complexes of N-methyl-isatin beta-thiosemicarbazone, thiosemicarbazide, and semicarbazide, but not methyl-isatin. No inactivation was observed when these compounds were used in the absence of copper sulfate. This confirms our previous observation that the activity of N-methyl-isatin beta-thiosemicarbazone is mediated by its thiosemicarbazone moiety and that the presence of copper is required for action. This represents the first time, to our knowledge, that semicarbazide has been found to possess antiviral activity. It is clear that these compounds act directly on deoxyribonucleic acid; whether the compounds also act on proteins has not been determined. PMID:769669

  12. Amiodarone inhibits the mitochondrial beta-oxidation of fatty acids and produces microvesicular steatosis of the liver in mice

    Energy Technology Data Exchange (ETDEWEB)

    Fromenty, B.; Fisch, C.; Labbe, G.; Degott, C.; Deschamps, D.; Berson, A.; Letteron, P.; Pessayre, D. (Institut National de la Sante et de la Recherche Medicale U24, Clichy (France))

    1990-12-01

    Amiodarone has been shown to produce microvesicular steatosis of the liver in some recipients. We have determined the effects of amiodarone on the mitochondrial oxidation of fatty acids in mice. In vitro, the formation of 14C-acid-soluble beta-oxidation products from (U-14C)palmitic acid by mouse liver mitochondria was decreased by 92% in the presence of 125 microM amiodarone and by 94% in the presence of 125 microM N-desethylamiodarone. Inhibition due to 100 or 150 microM amiodarone persisted in the presence of 5 mM acetoacetate, whereas acetoacetate totally relieved inhibition due to 15 microM rotenone. In vivo, exhalation of (14C)CO2 from (U-14C)palmitic acid was decreased by 31, 40, 58 and 78%, respectively, in mice receiving 19, 25, 50 and 100 mg.kg-1 of amiodarone hydrochloride 1 hr before the administration of (U-14C)palmitic acid. One hour after 100 mg.kg-1, the exhalation of (14C)CO2 from (1-14C)palmitic acid, (1-14C)octanoic acid or (1-14C)butyric acid was decreased by 78, 72 and 53%, respectively. Exhalation of (14C)CO2 from (1-14C)palmitic acid was normal between 6 and 9 hr after administration of 100 mg.kg-1 of amiodarone hydrochloride, but was still inhibited by 71 and 37%, 24 and 48 hr after 600 mg.kg-1. Twenty four hours after the latter dose of amiodarone, hepatic triglycerides were increased by 150%, and there was microvesicular steatosis of the liver. We conclude that amiodarone inhibits the mitochondrial beta-oxidation of fatty acids and produces microvesicular steatosis of the liver in mice.

  13. Intersubunit bridge formation governs agonist efficacy at nicotinic acetylcholine alpha4beta2 receptors

    DEFF Research Database (Denmark)

    Rohde, Line Aagot Hede; Ahring, Philip Kiær; Jensen, Marianne Lerbech;

    2012-01-01

    The a4ß2 subtype of the nicotinic acetylcholine receptor (nAChR) has been pursued as a drug target for treatment of psychiatric and neurodegenerative disorders and smoking cessation aids for decades. Still, a thorough understanding of structure-function relationships of a4ß2 agonists is lacking....... Using binding experiments, electrophysiology and X-ray crystallography we have investigated a consecutive series of five prototypical pyridine-containing agonists derived from 1-(pyridin-3-yl)-1,4-diazepane. A correlation between binding affinities at a4ß2 and the acetylcholine binding protein from...

  14. Acetylcholine release in mouse hippocampal CA1 preferentially activates inhibitory-selective interneurons via alpha4 beta2* nicotinic receptor activation

    Directory of Open Access Journals (Sweden)

    L. Andrew Bell

    2015-04-01

    Full Text Available Acetylcholine (ACh release onto nicotinic receptors directly activates subsets of inhibitory interneurons in hippocampal CA1. However, the specific interneurons activated and their effect on the hippocampal network is not completely understood. Therefore, we investigated subsets of hippocampal CA1 interneurons that respond to ACh release through the activation of nicotinic receptors and the potential downstream effects this may have on hippocampal CA1 network function. ACh was optogenetically released in mouse hippocampal slices by expressing the excitatory optogenetic protein oChIEF-tdTomato in medial septum/diagonal band of Broca cholinergic neurons using Cre recombinase-dependent adeno-associated viral mediated transfection. The actions of optogenetically released ACh were assessed on both pyramidal neurons and different interneuron subtypes via whole cell patch clamp methods. Vasoactive intestinal peptide (VIP-expressing interneurons that selectively innervate other interneurons (VIP/IS were excited by ACh through the activation of nicotinic receptors containing alpah4 and beta2 subunits (alpha4 beta2*. ACh release onto VIP/IS was presynaptically inhibited by M2 muscarinic autoreceptors. ACh release produced spontaneous inhibitory postsynaptic current (sIPSC barrages blocked by dihydro-beta-erythroidine in interneurons but not pyramidal neurons. Optogenetic suppression of VIP interneurons did not inhibit these sIPSC barrages suggesting other interneuron-selective interneurons were also excited by 42* nicotinic receptor activation. In contrast, interneurons that innervate pyramidal neuron perisomatic regions were not activated by ACh release onto nicotinic receptors. Therefore, we propose ACh release in CA1 facilitates disinhibition through activation of 42* nicotinic receptors on interneuron-selective interneurons whereas interneurons that innervate pyramidal neurons are less affected by nicotinic receptor activation.

  15. Population growth of Varroa destructor (Acari: Varroidae) in commercial honey bee colonies treated with beta plant acids

    OpenAIRE

    DeGrandi-Hoffman, Gloria; Ahumada, Fabiana; Curry, Robert; Probasco, Gene; Schantz, Lloyd

    2014-01-01

    Varroa (Varroa destuctor Anderson and Trueman) populations in honey bee (Apis mellifera L.) colonies might be kept at low levels by well-timed miticide applications. HopGuard® (HG) that contains beta plant acids as the active ingredient was used to reduce mite populations. Schedules for applications of the miticide that could maintain low mite levels were tested in hives started from either package bees or splits of larger colonies. The schedules were developed based on defined parameters for...

  16. c-fos gene induction by interleukin 2: identification of the critical cytoplasmic regions within the interleukin 2 receptor beta chain.

    OpenAIRE

    Hatakeyama, M; Kawahara, A; Mori, H.; Shibuya, H.; Taniguchi, T.

    1992-01-01

    Interleukin 2 (IL-2) plays a critical role in the growth and differentiation of lymphoid cells. The IL-2 signal is delivered intracellularly by the IL-2 receptor beta chain (IL-2R beta); however, the mechanism by which the signal reaches the nucleus remains unclear. In this study, we demonstrate the rapid activation of c-fos protooncogene transcription by IL-2 and provide evidence that the serum-responsive element (SRE) within the c-fos promoter is responsible for the activation in a murine p...

  17. Estrogen receptor beta activation prevents glucocorticoid receptor-dependent effects of the central nucleus of the amygdala on behavior and neuroendocrine function.

    Science.gov (United States)

    Weiser, Michael J; Foradori, Chad D; Handa, Robert J

    2010-06-01

    Neuropsychiatric disorders such as anxiety and depression have formidable economic and societal impacts. A dysregulation of the hypothalamo-pituitary-adrenal (HPA) axis leading to elevated endogenous glucocorticoid levels is often associated with such disorders. Chronically high glucocorticoid levels may act upon the central nucleus of the amygdala (CeA) to alter normally adaptive responses into those that are maladaptive and detrimental. In addition to glucocorticoids, other steroid hormones such as estradiol and androgens can also modify hormonal and behavioral responses to threatening stimuli. In particular, estrogen receptor beta (ERbeta) agonists have been shown to be anxiolytic. Consequently, these experiments addressed the hypothesis that the selective stimulation of glucocorticoid receptor (GR) in the CeA would increase anxiety-like behaviors and HPA axis reactivity to stress, and further, that an ERbeta agonist could modulate these effects. Young adult female Sprague-Dawley rats were ovariectomized and bilaterally implanted via stereotaxic surgery with a wax pellet containing the selective GR agonist RU28362 or a blank pellet, to a region just dorsal to the CeA. Four days later, animals were administered the ERbeta agonist S-DPN or vehicle (with four daily sc injections). Anxiety-type behaviors were measured using the elevated plus maze (EPM). Central RU28362 implants caused significantly higher anxiety-type behaviors in the EPM and greater plasma CORT levels than controls given a blank central implant. Moreover, S-DPN treated animals, regardless of type of central implant, displayed significantly lower anxiety-type behaviors and post-EPM plasma CORT levels than vehicle treated controls or vehicle treated animals implanted with RU28362. These results indicate that selective activation of GR within the CeA is anxiogenic, and peripheral administration of an ERbeta agonist can overcome this effect. These data suggest that estradiol signaling via ERbeta

  18. Novel {beta}-cyclodextrin modified CdTe quantum dots as fluorescence nanosensor for acetylsalicylic acid and metabolites

    Energy Technology Data Exchange (ETDEWEB)

    Algarra, M. [Centro de Geologia do Porto, Faculdade de Ciencias, Universidade do Porto, Rua do Campo Alegre 687, 4169-007 Porto (Portugal); Campos, B.B.; Aguiar, F.R.; Rodriguez-Borges, J.E. [Centro de Investigacao em Quimica (CIQ-UP), Faculdade de Ciencias da Universidade do Porto, Rua do Campo Alegre 687, 169-007 Porto (Portugal); Esteves da Silva, J.C.G., E-mail: jcsilva@fc.up.pt [Centro de Investigacao em Quimica (CIQ-UP), Faculdade de Ciencias da Universidade do Porto, Rua do Campo Alegre 687, 169-007 Porto (Portugal)

    2012-05-01

    {beta}-Cyclodextrin was modified with 11-[(ethoxycarbonyl)thio]undecanoic acid and used as a capping agent, together with mercaptosuccinic acid, to prepare water-stable CdTe quantum dots. The water soluble quantum dot obtained displays fluorescence with a maximum emission at 425 nm (under excitation at 300 nm) with lifetimes of 0.53, 4.8, 181, and 44.1 ns, respectively. The S-{beta}CD-MSA-CdTe can act as a nanoprobe that is due to the affinity of the cyclodextrin moiety for selected substances such as acetylsalicylic acid (ASA) and its metabolites as foreign species. The fluorescence of the S-{beta}CD-MSA-CdTe is enhanced on addition of ASA. Linear calibration plots are observed with ASA in concentrations between 0 and 1 mg/l, with a limit of detection at 8.5 Multiplication-Sign 10{sup -9} mol/l (1.5 ng/ml) and a precision as relative standard deviation of 1% (0.05 mg/l). The interference effect of certain compounds as ascorbic acid and its main metabolites such as salicylic, gentisic and salicyluric acid upon the obtained procedure was studied. Highlights: Black-Right-Pointing-Pointer Nanosensors constituted by CdTe quantum dots capped with modified cyclodextrin. Black-Right-Pointing-Pointer This nanomaterial shows fluorescence properties compatible with a semiconductor quantum dot. Black-Right-Pointing-Pointer The nanosensor shows fluorescence enhancement when inclusion complexes are formed with acetylsalicylic acid. Black-Right-Pointing-Pointer This nanomaterial has nanosensor potential taking into consideration the formation stability of the inclusion complex.

  19. γ-Hydroxybutyric acid (GHB is not an agonist of extrasynaptic GABAA receptors.

    Directory of Open Access Journals (Sweden)

    William M Connelly

    Full Text Available γ-Hydroxybutyric acid (GHB is an endogenous compound and a drug used clinically to treat the symptoms of narcolepsy. GHB is known to be an agonist of GABAB receptors with millimolar affinity, but also binds with much higher affinity to another site, known as the GHB receptor. While a body of evidence has shown that GHB does not bind to GABAA receptors widely, recent evidence has suggested that the GHB receptor is in fact on extrasynaptic α4β1δ GABAA receptors, where GHB acts as an agonist with an EC50 of 140 nM. We investigated three neuronal cell types that express a tonic GABAA receptor current mediated by extrasynaptic receptors: ventrobasal (VB thalamic neurons, dentate gyrus granule cells and striatal medium spiny neurons. Using whole-cell voltage clamp in brain slices, we found no evidence that GHB (10 µM induced any GABAA receptor mediated current in these cell types, nor that it modulated inhibitory synaptic currents. Furthermore, a high concentration of GHB (3 mM was able to produce a GABAB receptor mediated current, but did not induce any other currents. These results suggest either that GHB is not a high affinity agonist at native α4β1δ receptors, or that these receptors do not exist in classical areas associated with extrasynaptic currents.

  20. γ-Hydroxybutyric acid (GHB) is not an agonist of extrasynaptic GABAA receptors.

    Science.gov (United States)

    Connelly, William M; Errington, Adam C; Crunelli, Vincenzo

    2013-01-01

    γ-Hydroxybutyric acid (GHB) is an endogenous compound and a drug used clinically to treat the symptoms of narcolepsy. GHB is known to be an agonist of GABAB receptors with millimolar affinity, but also binds with much higher affinity to another site, known as the GHB receptor. While a body of evidence has shown that GHB does not bind to GABAA receptors widely, recent evidence has suggested that the GHB receptor is in fact on extrasynaptic α4β1δ GABAA receptors, where GHB acts as an agonist with an EC50 of 140 nM. We investigated three neuronal cell types that express a tonic GABAA receptor current mediated by extrasynaptic receptors: ventrobasal (VB) thalamic neurons, dentate gyrus granule cells and striatal medium spiny neurons. Using whole-cell voltage clamp in brain slices, we found no evidence that GHB (10 µM) induced any GABAA receptor mediated current in these cell types, nor that it modulated inhibitory synaptic currents. Furthermore, a high concentration of GHB (3 mM) was able to produce a GABAB receptor mediated current, but did not induce any other currents. These results suggest either that GHB is not a high affinity agonist at native α4β1δ receptors, or that these receptors do not exist in classical areas associated with extrasynaptic currents.

  1. beta-oxidation modulates metabolic competition between eicosapentaenoic acid and arachidonic acid regulating prostaglandin E(2) synthesis in rat hepatocytes-Kupffer cells

    DEFF Research Database (Denmark)

    Du, Zhen-Yu; Ma, Tao; Winterthun, Synnøve;

    2010-01-01

    and eicosapentaenoic acid (EPA) for PGE(2) synthesis in a rat hepatocyte-Kupffer cell (HPC/KC) co-culture system when the cellular oxidation capacity was enhanced by exogenous l-carnitine. We demonstrate that in the absence of l-carnitine, 1) beta-oxidation rates of EPA and AA were comparable in HPCs and in KCs; 2) AA......) significantly increased beta-oxidation of EPA in HPCs, but only marginally elevated the oxidation of AA in HPCs and the oxidation of both fatty acids in KCs; 2) decreased the esterification, but did not alter the preferential incorporation of AA into glycerolipids; and 3) alleviated the significant competitive...... and not EPA was preferentially incorporated into glycerolipids; and 3) addition of EPA significantly decreased AA-dependent PGE(2) synthesis in HPCs and cyclooxygenase-2 (COX-2) expression in co-cultured HPCs/KCs. However, enhancing the cellular oxidation capacity by the addition of l-carnitine 1...

  2. Maintained activity of glycogen synthase kinase-3{beta} despite of its phosphorylation at serine-9 in okadaic acid-induced neurodegenerative model

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Yong-Whan [Department of Anatomy and Cell Biology, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Yoon, Seung-Yong, E-mail: ysy@amc.seoul.kr [Department of Anatomy and Cell Biology, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Institute for Biomacromolecules, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Choi, Jung-Eun [Department of Anatomy and Cell Biology, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Institute for Biomacromolecules, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Kim, Sang-Min [Department of Anatomy and Cell Biology, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Lee, Hui-Sun; Choe, Han [Department of Physiology, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Institute for Biomacromolecules, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Lee, Seung-Chul [CrystalGenomics, Seoul (Korea, Republic of); Kim, Dong-Hou, E-mail: dhkim@amc.seoul.kr [Department of Anatomy and Cell Biology, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Institute for Biomacromolecules, University of Ulsan College of Medicine, Seoul (Korea, Republic of)

    2010-04-30

    Glycogen synthase kinase-3{beta} (GSK3{beta}) is recognized as one of major kinases to phosphorylate tau in Alzheimer's disease (AD), thus lots of AD drug discoveries target GSK3{beta}. However, the inactive form of GSK3{beta} which is phosphorylated at serine-9 is increased in AD brains. This is also inconsistent with phosphorylation status of other GSK3{beta} substrates, such as {beta}-catenin and collapsin response mediator protein-2 (CRMP2) since their phosphorylation is all increased in AD brains. Thus, we addressed this paradoxical condition of AD in rat neurons treated with okadaic acid (OA) which inhibits protein phosphatase-2A (PP2A) and induces tau hyperphosphorylation and cell death. Interestingly, OA also induces phosphorylation of GSK3{beta} at serine-9 and other substrates including tau, {beta}-catenin and CRMP2 like in AD brains. In this context, we observed that GSK3{beta} inhibitors such as lithium chloride and 6-bromoindirubin-3'-monoxime (6-BIO) reversed those phosphorylation events and protected neurons. These data suggest that GSK3{beta} may still have its kinase activity despite increase of its phosphorylation at serine-9 in AD brains at least in PP2A-compromised conditions and that GSK3{beta} inhibitors could be a valuable drug candidate in AD.

  3. Prediction of selective estrogen receptor beta agonist using open data and machine learning approach

    Directory of Open Access Journals (Sweden)

    Niu AQ

    2016-07-01

    Full Text Available Ai-qin Niu,1 Liang-jun Xie,2 Hui Wang,1 Bing Zhu,1 Sheng-qi Wang3 1Department of Gynecology, the First People’s Hospital of Shangqiu, Shangqiu, Henan, People’s Republic of China; 2Department of Image Diagnoses, the Third Hospital of Jinan, Jinan, Shandong, People’s Republic of China; 3Department of Mammary Disease, Guangdong Provincial Hospital of Chinese Medicine, the Second Clinical College of Guangzhou University of Chinese Medicine, Guangzhou, People’s Republic of China Background: Estrogen receptors (ERs are nuclear transcription factors that are involved in the regulation of many complex physiological processes in humans. ERs have been validated as important drug targets for the treatment of various diseases, including breast cancer, ovarian cancer, osteoporosis, and cardiovascular disease. ERs have two subtypes, ER-α and ER-β. Emerging data suggest that the development of subtype-selective ligands that specifically target ER-β could be a more optimal approach to elicit beneficial estrogen-like activities and reduce side effects. Methods: Herein, we focused on ER-β and developed its in silico quantitative structure-activity relationship models using machine learning (ML methods. Results: The chemical structures and ER-β bioactivity data were extracted from public chemogenomics databases. Four types of popular fingerprint generation methods including MACCS fingerprint, PubChem fingerprint, 2D atom pairs, and Chemistry Development Kit extended fingerprint were used as descriptors. Four ML methods including Naïve Bayesian classifier, k-nearest neighbor, random forest, and support vector machine were used to train the models. The range of classification accuracies was 77.10% to 88.34%, and the range of area under the ROC (receiver operating characteristic curve values was 0.8151 to 0.9475, evaluated by the 5-fold cross-validation. Comparison analysis suggests that both the random forest and the support vector machine are superior

  4. Expression and localization of the omega-3 fatty acid receptor GPR120 in human term placenta.

    Science.gov (United States)

    Lager, S; Ramirez, V I; Gaccioli, F; Jansson, T; Powell, T L

    2014-07-01

    Fatty acids can function as signaling molecules, acting through receptors in the cytosol or on the cell surface. G-Protein Receptor (GPR)120 is a membrane-bound receptor mediating anti-inflammatory and insulin-sensitizing effects of the omega-3 fatty acid docohexaenoic acid (DHA). GPR120 dysfunction is associated with obesity in humans. Cellular localization of GPR120 and the influence of maternal obesity on GPR120 protein expression in the placenta are unknown. Herein we demonstrate that GPR120 is predominantly expressed in the microvillous membrane (MVM) of human placenta and that the expression level of this receptor in MVM is not altered by maternal body mass index (BMI).

  5. Radiolabeled high affinity peptidomimetic antagonist selectively targets {alpha}{sub v}{beta}{sub 3} receptor-positive tumor in mice

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Beom-Su [Department of Nuclear Medicine, Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892 (United States); Lim, Esther [Department of Radiology, Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892 (United States); Hee Park, Seung [Department of Nuclear Medicine, Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892 (United States); Shin, In Soo [Department of Nuclear Medicine, Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892 (United States); Danthi, S. Narasimhan [Department of Radiology, Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892 (United States); Hwang, In Sook [Department of Nuclear Medicine, Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892 (United States); Le, Nhat [Department of Nuclear Medicine, Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892 (United States); Yu, Sarah [Department of Nuclear Medicine, Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892 (United States); Xie Jianwu [Department of Radiology, Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892 (United States); Li, King C.P. [Department of Radiology, Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892 (United States); Carrasquillo, Jorge A. [Department of Nuclear Medicine, Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892 (United States); Paik, Chang H. [Department of Nuclear Medicine, Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892 (United States)]. E-mail: cpaik@mail.nih.gov

    2007-05-15

    Objectives: The aim of this research was to synthesize radiolabeled peptidomimetic integrin {alpha}{sub v}{beta}{sub 3} antagonists that selectively target integrin {alpha}{sub v}{beta}{sub 3} receptor and clear rapidly from the whole body. Methods: Integrin {alpha}{sub v}{beta}{sub 3} antagonists, 4-[2-(3,4,5,6-tetrahydropyrimidine-2-ylamino) ethyloxy]benzoyl-2-(S)-aminoethylsulfonyl-amino-{beta}-alanine (IA) and 4-[2-(3,4,5,6-tetrahydro-pyrimidin-2-ylamino)-ethyloxy]benzoyl-2-(S)-[N- (3-amino-neopenta-1-carbamyl)]-aminoethylsulfonylamino-{beta}-alanine hydrochloride (IAC), a hydrophobic carbamate derivative of IA, were conjugated with 2-p-isothiocyanatobenzyl-DOTA at the amino terminus and labeled with {sup 111}In. The {sup 111}In labeled IA and IAC were subjected to in vitro receptor binding, biodistribution and imaging studies using nude mice bearing the receptor-positive M21 human melanoma xenografts. Results: The {sup 111}In-labeled IA (40%) and -IAC (72%) specifically bound in vitro to {alpha}{sub v}{beta}{sub 3} (0.8 {mu}M) at a molar excess. This receptor binding was completely blocked by a molar excess of cold IA to {alpha}{sub v}{beta}{sub 3}. The higher receptor-binding affinity of the {sup 111}In-labeled IAC was reflected in higher tumor uptake and retention: 5.6{+-}1.4 and 4.5{+-}0.7 %ID/g vs. 3.8{+-}0.9 and 2.0{+-}0.3 %ID/g for the {sup 111}In-labeled IA at 0.33 and 2 h. The tumor uptakes were inhibited by the co-injection of 200 {mu}g of IA, indicating that the uptake was receptor mediated. These antagonists were excreted primarily via the renal system. The {sup 111}In activity retained in the whole body was quite comparable between the {sup 111}In-labeled IA (24% ID) and the {sup 111}In-labeled IAC (33% ID) at 2 h. The higher peak tumor uptake and longer retention resulted in higher tumor-to-background ratios for the {sup 111}In-labeled IAC at 2 h with 9.7, 2.3, 0.8, 1.9, 7.1, 2.2, 0.9, 3.7 and 9.9 for blood, liver, kidney, lung, heart, stomach

  6. The Effect of Genetic Variation of the Retinoic Acid Receptor-Related Orphan Receptor C Gene on Fatness in Cattle

    OpenAIRE

    Barendse, W.; Bunch, R. J.; Kijas, J. W.; M. B. Thomas

    2007-01-01

    Genotypes at the retinoic acid receptor-related orphan receptor C (RORC) gene were associated with fatness in 1750 cattle. Ten SNPs were genotyped in RORC and the adjacent gene leucine-rich repeat neuronal 6D (LRRN6D) to map the QTL, 7 of which are in a 4.2-kb sequence around the ligand-binding domain of the RORC gene. Of the 29 inferred haplotypes for these SNPs, 2 have a combined frequency of 54.6% while the top 5 haplotypes have a combined frequency of 85.3%. The average D′ value of linkag...

  7. Control of Listeria monocytogenes on frankfurters by dipping in hops beta acids solutions.

    Science.gov (United States)

    Shen, Cangliang; Geornaras, Ifigenia; Kendall, Patricia A; Sofos, John N

    2009-04-01

    Hops beta acids (HBA) are parts of hops flowers used in beer brewing and have shown antilisterial activity in bacteriological broth. The U.S. Department of Agriculture, Food Safety and Inspection Service has approved HBA for use to control Listeria monocytogenes on ready-to-eat meat products. This study evaluated the effects of HBA as dipping solutions to control L. monocytogenes during storage of frankfurters. Frankfurters (two replicates and three samples each) were inoculated (1.9 +/- 0.1 log CFU/cm2) with L. monocytogenes (10-strain mixture), dipped (2 min, 25 +/- 2 degrees C) in HBA solutions (0.03, 0.06, and 0.10%) or distilled water, and then vacuum packaged and stored at 4 or 10 degrees C for up to 90 and 48 days, respectively. Samples were periodically analyzed for microbial survival and growth on tryptic soy agar plus 0.6% yeast extract and PALCAM agar. Dipping in HBA solutions caused immediate L. monocytogenes reductions (P < 0.05) of 1.3 to 1.6 log CFU/cm2, whereas distilled water reduced counts by 1.0 log CFU/cm2. Pathogen growth was completely suppressed (P < 0.05) for 30 to 50 (4 degrees C) or 20 to 28 (10 degrees C) days on frankfurters dipped in HBA solutions, with antilisterial effects increasing with higher concentrations (0.03 to 0.10%). Fitting the data with the Baranyi model confirmed that the lag-phase duration of the pathogen was extended, and the growth rate was decreased on samples dipped in HBA solutions. Therefore, HBA may be considered for use to improve the microbial safety of ready-to-eat meat products, provided that future studies show no adverse effects on sensory qualities and that their use is economically feasible.

  8. Effect of hemolysis on nonesterified fatty acid and beta-hydroxybutyrate concentrations in bovine blood.

    Science.gov (United States)

    Stokol, Tracy; Nydam, Daryl V

    2006-09-01

    Nonesterified fatty acid (NEFA) and beta-hydroxybutyrate (BHB) assays are used for evaluating dairy herds for negative energy balance and subclinical ketosis, respectively. Hemolysis is a common artifact in samples submitted to diagnostic laboratories. The effect of hemolysis on NEFA and BHB in bovine serum was determined. Hemolysis was introduced into 26 serum samples by adding serial dilutions of a red cell hemolysate, prepared by repeated freeze-thawing of EDTA-anticoagulated bovine blood. NEFA, BHB, and degree of hemolysis (hemolytic index) were measured by an automated chemistry analyzer. Two endpoint assays that differed by inclusion of a sample blank were used for NEFA measurement. A kinetic enzymatic assay with 2 reagent sources was used for BHB measurement. The assessed methods yielded similar NEFA or BHB results in baseline, nonhemolyzed samples (median NEFA: 0.25 mEq/L, median BHB: 3 mg/dL, median hemolytic index: 8 units). NEFA results were adversely affected by hemolysis, with values increasing significantly with higher degrees of hemolysis. Median values increased above a critical medical decision limit (0.40 mEq/L) at a hemolytic index of 506 units (marked hemolysis). This increase was prevented by inclusion of a sample blank. Result interpretation was affected in individual animals when samples were moderately hemolyzed (median hemolytic index: 258 units). In contrast, BHB results were unaffected by hemolysis with either reagent source. Thus, assays for measuring NEFAs should include a sample blank and NEFA results should not be interpreted in moderately to markedly hemolyzed bovine samples, because result accuracy cannot be assured.

  9. Herpes simplex virus infection is sensed by both Toll-like receptors and retinoic acid-inducible gene- like receptors, which synergize to induce type I interferon production

    DEFF Research Database (Denmark)

    Rasmussen, Simon Brandtoft; Jensen, Søren B; Nielsen, C;

    2009-01-01

    The innate antiviral response is initiated by pattern recognition receptors, which recognize viral pathogen-associated molecular patterns. Here we show that retinoic acid-inducible gene (RIG)-I-like receptors (RLRs) in cooperation with Toll-like receptor (TLR) 9 is required for expression of type...

  10. Interaction of Beta-Hydroxy-Beta-Methylbutyrate Free Acid and Adenosine Triphosphate on Muscle Mass, Strength, and Power in Resistance Trained Individuals.

    Science.gov (United States)

    Lowery, Ryan P; Joy, Jordan M; Rathmacher, John A; Baier, Shawn M; Fuller, John C; Shelley, Mack C; Jäger, Ralf; Purpura, Martin; Wilson, Stephanie M C; Wilson, Jacob M

    2016-07-01

    Lowery, RP, Joy, JM, Rathmacher, JA, Baier, SM, Fuller, JC Jr, Shelley, MC II, Jäger, R, Purpura, M, Wilson, SMC, and Wilson, JM. Interaction of beta-hydroxy-beta-methylbutyrate free acid and adenosine triphosphate on muscle mass, strength, and power in resistance trained individuals. J Strength Cond Res 30(7): 1843-1854, 2016-Adenosine-5'-triphosphate (ATP) supplementation helps maintain performance under high fatiguing contractions and with greater fatigue recovery demands also increase. Current evidence suggests that the free acid form of β-hydroxy-β-methylbutyrate (HMB-FA) acts by speeding regenerative capacity of skeletal muscle after high-intensity or prolonged exercise. Therefore, we investigated the effects of 12 weeks of HMB-FA (3 g) and ATP (400 mg) administration on lean body mass (LBM), strength, and power in trained individuals. A 3-phase double-blind, placebo-, and diet-controlled study was conducted. Phases consisted of an 8-week periodized resistance training program (phase 1), followed by a 2-week overreaching cycle (phase 2), and a 2-week taper (phase 3). Lean body mass was increased by a combination of HMB-FA/ATP by 12.7% (p power were increased in the HMB-FA/ATP-supplemented group compared with the placebo-supplemented group, and the 12-week increases were 21.5 and 23.7%, respectively. During the overreaching cycle, strength and power declined in the placebo group (4.3-5.7%), whereas supplementation with HMB-FA/ATP resulted in continued strength gains (1.3%). In conclusion, HMB-FA and ATP in combination with resistance exercise training enhanced LBM, power, and strength. In addition, HMB-FA plus ATP blunted the typical response to overreaching, resulting in a further increase in strength during that period. It seems that the combination of HMB-FA/ATP could benefit those who continuously train at high levels such as elite athletes or military personnel.

  11. Disruption of estrogen receptor beta in mice brain results in pathological alterations resembling Alzheimer disease

    Institute of Scientific and Technical Information of China (English)

    Qing-hong ZHANG; Yan-hong HUANG; Yu-zhen HU; Geng-ze WEI; Xue-feng HAN; Shun-yan LU; Yu-feng ZHAO

    2004-01-01

    AIM: To study the pathological characteristics of the mice with estrogen receptor β (ERβ) disruption in brain.METHODS: Immunohistochemistry method was applied in the study. RESULTS: β-Amyloid peptide(Aβ42) and apolipoprotein E (ApoE) immunoreactive substances were accumulated notably in cortex and limbic structures such as the hippocampus and amygdala in brain, resembling the pathological changes of human Alzheimer disease (AD). Aβ formed cloudy-like deposits in parenchyma of brain, while apoE also deposited along or surrounding the blood vessels. CONCLUSIONS: ERβ is crucial to the development of neural degenerative disease, so modulation of Aβ metabolism via ERβ signal pathway might be beneficial for AD prevention or therapy.

  12. Relationship between Beta Estrogen Receptor Polymorphism and Psychosocial Stress on Menopausal Women

    Directory of Open Access Journals (Sweden)

    Elizabet Catherine Jusuf

    2016-08-01

    Full Text Available Menopause is a normal stage of development experienced by elderly women. This study aimed to evaluate the association between polymorphisms of ERα & ERβ and the incidence of psychosocial stress on menopausal women. This research was conducted in BLU dr. Wahidin Sudirohusodo and affiliate hospitals of Department of Obstetrics and Gynecology Medical Faculty of Hasanuddin University in Makassar, using cross-sectional design. Obtained sample of 102 subjects who met the inclusion criteria and examined polymorphisms receptors ERβ. Data were statistically analyzed using the chi square test with p value <0.05. Results showed that respondents who experienced psychosocial stress has the most ERβ polymorphism homozygous dominant AA. There is ERβ polymorphism relationship with the occurrence of psychosocial stress in menopausal women.

  13. Cloning of somatolactin alpha, beta forms and the somatolactin receptor in Atlantic salmon: Seasonal expression profile in pituitary and ovary of maturing female broodstock

    Directory of Open Access Journals (Sweden)

    Taranger Geir

    2008-09-01

    Full Text Available Abstract Background Somatolactin (Sl is a fish specific adenohypophyseal peptide hormone related to growth hormone (Gh. Some species, including salmonids, possess two forms: Sl alpha and Sl beta. The somatolactin receptor (slr is closely related to the growth hormone receptor (ghr. Sl has been ascribed many physiological functions, including a role in sexual maturation. In order to clarify the role of Sl in the sexual maturation of female Atlantic salmon (Salmo salar, the full length cDNAs of slr, Sl alpha and Sl beta were cloned and their expression was studied throughout a seasonal reproductive cycle using real-time quantitative PCR (RTqPCR. Methods Atlantic salmon Sl alpha, Sl beta and slr cDNAs were cloned using a PCR approach. Gene expression of Sl alpha, SL beta and slr was studied using RTqPCR over a 17 month period encompassing pre-vitellogenesis, vitellogenesis, ovulation and post ovulation in salmon females. Histological examination of ovarian samples allowed for the classification according to the degree of follicle maturation into oil drop, primary, secondary or tertiary yolk stage. Results The mature peptide sequences of Sl alpha, Sl beta and slr are highly similar to previously cloned salmonid forms and contained the typical motifs. Phylogenetic analysis of Atlantic salmon Sl alpha and Sl beta shows that these peptides group into the two Sl clades present in some fish species. The Atlantic salmon slr grouped with salmonid slr amongst so-called type I ghr. An increase in pituitary Sl alpha and Sl beta transcripts before and during spawning, with a decrease post-ovulation, and a constant expression level of ovarian slr were observed. There was also a transient increase in Sl alpha and Sl beta in May prior to transfer from seawater to fresh water and ensuing fasting. Conclusion The up-regulation of Sl alpha and Sl beta during vitellogenesis and spawning, with a subsequent decrease post-ovulation, supports a role for Sl during gonadal

  14. Immunolocalization of estrogen receptor beta in the epididymis of mature and immature pigs.

    Directory of Open Access Journals (Sweden)

    M Maggiolini

    2004-03-01

    Full Text Available A growing body of evidence suggests a role of estrogens in the male reproduction via their specific estrogen receptors (ERalpha/ERbeta. Estrogen receptor distribution along the genital tract tissues has been described in different species, but it is unknown in the pig. Therefore, the aim of the present study was to localize ERbeta in the epididymis of mature and immature pigs (aged 2 and 18 months, respectively. Immunohistochemistry was carried out on paraffin-embedded tissues using a mouse anti-human monoclonal IgG against ERbeta as the primary antibody, and a goat anti-mouse biotinylated IgG as the secondary antibody. Avidin-biotin-peroxidase complex was then applied followed by diaminobenzidine. In immature pigs, the epithelial cells from the caput, corpus and cauda epididymis showed no or very weak immunoreactivity for ERbeta, whereas they were all strongly immmunoreactive in mature pigs. A various intensity of immunostaining from weak to strong in the smooth muscle cells as well as in the connective tissue cells were detected in the epididymis of both, young and adult pigs. This is the first report on the cellular localization of ERbeta protein in porcine epidydimis. The present study demonstrated that (1 irrespectively of the epididymal region, the epithelial cells of caput, corpus and cauda epididymis of mature pigs revealed a strong immunoreactivity for ERbeta, and (2 ERbeta expression in the epididymal epithelium is regulated by puberty. Finally, although the biological activity of ERbeta has not yet been established, the results of the present study suggest its involvement in estrogen modulation of pig epididymal function.

  15. The effect pathway of retinoic acid through regulation of retinoic acid receptor in gastric cancer cells

    Institute of Scientific and Technical Information of China (English)

    Su Liu; Qiao Wu; Zheng-Ming Chen; Wen-Jin Su

    2001-01-01

    AIM To evaluate the role of RARa gene in mediating the growth inhibitory effect of ail-trans retinoic acid (ATRA)on gastric cancer cells.``METHODS The expression levels of retinoic acid receptors (RARs) in gastric cancer cells were detected by Northern blot. Transient transfection and chlorophenicol acetyl transferase (CAT) assay were used to show the transcriptional activity of β retinoic acid response element (βRARE) and AP-l activity. Cell growth inhibition was determined by MTT assay and anchorage-independent growth assay, respectively. Stable transfection was performed by the method of Lipofectamine, and the cells were screened by G418.``RESULTS ATRA could induce expression level of RARα in MGC80-3, BGCC8823 and SGC-7901 cells obviously,resulting in growth inhibition of these cell lines. After sense RARa gene was transfected into MKN-45 cells that expressed rather Iow level of RARα and could not be induced by ATRA, the cell growth was inhibited by ATRA markedly. In contrast, when antisense RARα gene was transfected into BGC-825 cells, a little inhibitory effect by ATRA was seen, compared with the parallel BGC-823cells. In transient transfection assay, ATRA effectively induced transcriptional activity of βRARE in MGC80-3,BGC.823, SGC-7902 and MKN/RARa cell lines, but not in MKN-45 and BGC/aRARa cell lines. Similar results were observed in measuring anti-AP-l activity by ATRA in these cancer cell lines.``CONCLUSION ATRA inhibits the growth of gastric cancer cells by up-regulating the level of RARa; RARa is the major mediator of ATRA action in gastric cancer cells; and adequate level of RAPa is required for ATRA effect on gastric cancer cells.``

  16. Concomitant targeting of EGF receptor, TGF-beta and SRC points to a novel therapeutic approach in pancreatic cancer.

    Directory of Open Access Journals (Sweden)

    Sophie Deharvengt

    Full Text Available To test the hypothesis that concomitant targeting of the epidermal growth factor receptor (EGFR and transforming growth factor-beta (TGF-β may offer a novel therapeutic approach in pancreatic cancer, EGFR silencing by RNA interference (shEGFR was combined with TGF-β sequestration by soluble TGF-β receptor II (sTβRII. Effects on colony formation in 3-dimensional culture, tumor formation in nude mice, and downstream signaling were monitored. In both ASPC-1 and T3M4 cells, either shEGFR or sTβRII significantly inhibited colony formation. However, in ASPC-1 cells, combining shEGFR with sTβRII reduced colony formation more efficiently than either approach alone, whereas in T3M4 cells, shEGFR-mediated inhibition of colony formation was reversed by sTβRII. Similarly, in vivo growth of ASPC-1-derived tumors was attenuated by either shEGFR or sTβRII, and was markedly suppressed by both vectors. By contrast, T3M4-derived tumors either failed to form or were very small when EGFR alone was silenced, and these effects were reversed by sTβRII due to increased cancer cell proliferation. The combination of shEGFR and sTβRII decreased phospho-HER2, phospho-HER3, phoshpo-ERK and phospho-src (Tyr416 levels in ASPC-1 cells but increased their levels in T3M4 cells. Moreover, inhibition of both EGFR and HER2 by lapatinib or of src by SSKI-606, PP2, or dasatinib, blocked the sTβRII-mediated antagonism of colony formation in T3M4 cells. Together, these observations suggest that concomitantly targeting EGFR, TGF-β, and src may constitute a novel therapeutic approach in PDAC that prevents deleterious cross-talk between EGFR family members and TGF-β-dependent pathways.

  17. Biostructural and pharmacological studies of bicyclic analogues of the 3-isoxazolol glutamate receptor agonist ibotenic acid

    DEFF Research Database (Denmark)

    Frydenvang, Karla Andrea; Pickering, Darryl S; Greenwood, Jeremy R;

    2010-01-01

    We describe an improved synthesis and detailed pharmacological characterization of the conformationally restricted analogue of the naturally occurring nonselective glutamate receptor agonist ibotenic acid (RS)-3-hydroxy-4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridine-7-carboxylic acid (7-HPCA, 5) at A...

  18. REACTIVITY PROFILE OF LIGANDS OF MAMMALIAN RETINOIC ACID RECEPTORS: A PRELIMINARY COREPA ANALYSIS

    Science.gov (United States)

    Retinoic acid and associated derivatives comprise a class of endogenous hormones that bind to and activate different families of retinoic acid receptors (RARs, RXRs), and control many aspects of vertebrate development. Identification of potential RAR and RXR ligands is of interes...

  19. The molecular basis of ligand interaction at free fatty acid receptor 4 (FFA4/GPR120)

    DEFF Research Database (Denmark)

    Hudson, Brian D; Shimpukade, Bharat; Milligan, Graeme;

    2014-01-01

    The long-chain fatty acid receptor FFA4 (previously GPR120) is receiving substantial interest as a novel target for the treatment of metabolic and inflammatory disease. This study examines for the first time the detailed mode of binding of both long-chain fatty acid and synthetic agonist ligands ...

  20. Activity of L-alpha-amino acids at the promiscuous goldfish odorant receptor 5.24

    DEFF Research Database (Denmark)

    Christiansen, Bolette; Wellendorph, Petrine; Bräuner-Osborne, Hans

    2006-01-01

    report the agonist activities of the 20 proteinogenic L-alpha-amino acids, and L-ornithine and L-citrulline, measured in an intracellular calcium release assay in mammalian tsA cells. The results show that receptor 5.24 is broadly activated by 19 of the tested L-alpha-amino acids and displays...

  1. Variations in maternal care alter corticosterone and 17beta-estradiol levels, estrous cycle and folliculogenesis and stimulate the expression of estrogen receptors alpha and beta in the ovaries of UCh rats

    Directory of Open Access Journals (Sweden)

    Amorim João PA

    2011-12-01

    Full Text Available Abstract Background Variations in maternal care are associated with neonatal stress, hormonal disturbances and reproductive injuries during adulthood. However, the effects of these variations on sex hormones and steroid receptors during ovary development remain undetermined. This study aimed to investigate whether variations in maternal care are able to influence the hormonal profile, follicular dynamics and expression of AR, ER-alpha and ER-beta in the ovaries of UCh rat offspring. Methods Twenty-four adult UCh rats, aged 120 days, were randomly divided into two groups (UChA and UChB and mated. Maternal care was assessed from birth (day 0 to the 10th postnatal day (PND. In adulthood, twenty adult female rats (UChA and UChB offspring; n = 10/group, aged 120 days, were euthanized by decapitation during the morning estrus. Results UChA females (providing high maternal care more frequently displayed the behaviors of carrying pups, as well as licking/grooming and arched back nursing cares. Also, mothers providing high care had elevated corticosterone levels. Additionally, offspring receiving low maternal care showed the highest estrous cycle duration, increased corticosterone and 17beta-estradiol levels, overexpression of receptors ER-alpha and ER-beta, increased numbers of primordial, antral and mature follicles and accentuated granulosa cell proliferation. Conclusions Our study suggests that low maternal care alters corticosterone and 17beta-estradiol levels, disrupting the estrous cycle and folliculogenesis and differentially regulating the expression of ER-alpha and ER-beta in the ovaries of adult rats.

  2. The implications of particle energy and acidic media on gross alpha and gross beta determination using liquid scintillation

    Energy Technology Data Exchange (ETDEWEB)

    Zapata-Garcia, D. [Laboratori de Radiologia Ambiental (LRA), Departament de Quimica Analitica, Universitat de Barcelona, Marti i Franques, 1-11 Planta 3, E-08028 Barcelona (Spain); Llaurado, M., E-mail: montse.llaurado@ub.edu [Laboratori de Radiologia Ambiental (LRA), Departament de Quimica Analitica, Universitat de Barcelona, Marti i Franques, 1-11 Planta 3, E-08028 Barcelona (Spain); Rauret, G. [Laboratori de Radiologia Ambiental (LRA), Departament de Quimica Analitica, Universitat de Barcelona, Marti i Franques, 1-11 Planta 3, E-08028 Barcelona (Spain)

    2012-04-15

    The interaction of humans with radioactivity present in the environment from natural and artificial sources necessitates an evaluation of its risk on human health. Gross alpha and gross beta activities can provide a rapid evaluation of the radioactive content of a sample and can be simultaneously determined by using liquid scintillation counters. However, calibration of the liquid scintillation counter is required and is affected by many factors, such as particle energy and the acidity of the media. This study investigates what effect the particle energy used for calibration has on misclassification and how to account for this misclassification in routine measurements. The variability in measurement produced by the final pH, as well as any acids used in sample treatment, was also studied. These results showed that the most commonly used acid for these types of analyses, HNO{sub 3}, produced a high amount of misclassifications at very low pH. The results improved when HCl was used to adjust the sample to low pH. - Highlights: Black-Right-Pointing-Pointer We study the effect of alpha and beta energies on PSA optimisation. Black-Right-Pointing-Pointer The optimum PSA shifts to higher values as the alpha energy increases. Beta energies do not affect it. Black-Right-Pointing-Pointer We study the effect of pH on the simultaneous determination of gross alpha/beta activities. Black-Right-Pointing-Pointer HNO{sub 3} produces a high amount of misclassification at very low pH. Black-Right-Pointing-Pointer The results improve when HCl is used to adjust the sample to low pH.

  3. Effects of hippocampal injections of a novel ligand selective for the alpha 5 beta 2 gamma 2 subunits of the GABA/benzodiazepine receptor on Pavlovian conditioning.

    Science.gov (United States)

    Bailey, David J; Tetzlaff, Julie E; Cook, James M; He, Xiaohui; Helmstetter, Fred J

    2002-07-01

    Benzodiazepine pharmacology has led to greater insight into the neural mechanisms underlying learning and anxiety. The synthesis of new compounds capable of modulating responses produced by these receptors has been made possible by the development of an isoform model of the GABA(A)/benzodiazepine receptor complex. In the current experiment, rats were pretreated with several concentrations of the novel ligand RY024 (an alpha 5 beta 2 gamma 2 -selective benzodiazepine receptor inverse agonist) in the hippocampus and were trained in a Pavlovian fear conditioning paradigm. RY024 independently produced fear-related behavior prior to training and, at the highest concentration, decreased the strength of conditioning observed 24 h after training. These data provide further evidence for the involvement of hippocampal GABA(A)/benzodiazepine receptors in learning and anxiety.

  4. Evaluation of branched chain fatty acid, BMIPP (. beta. -methyl-. omega. -(p-iodophenyl)-pentadecanoic acid) for the myocardial imaging. Basic experiment

    Energy Technology Data Exchange (ETDEWEB)

    Kawamura, Yasuaki; Morishita, Takeshi; Yamazaki, Junichi and others

    1988-11-01

    Iodine-123 labeled branched chain fatty acid BMIPP (/sup ..beta../-methyl-..omega..-(p-iodophenyl)-pentadecanoic acid) was evaluated for the myocardial imaging experimentally. /sup 123/I-BMIPP was accumulated in the heart at 2 - 4 minutes after injection and retention in the heart was remarkable at 30 minutes. In the acute canine infarction model, infarcted area was recognized as a defect. Furthermore, in comparison between /sup 123/I-BMIPP and /sup 201/Tl-Cl, discrepancy between these images was recognized in the ischemic and infarcted area. BMIPP is of use in not only cardiomyopathy and hypertension, but ischemic heart desease.

  5. Energy expenditure, body composition and insulin response to glucose in male twins discordant for the Trp64Arg polymorphism of the beta3-adrenergic receptor gene

    DEFF Research Database (Denmark)

    Højlund, K; Christiansen, C; Bjørnsbo, K S;

    2006-01-01

    AIM: The tryptophan to arginine change in position 64 (Trp64Arg) polymorphism of the beta3-adrenergic receptor (beta3AR) gene has been associated with an increased prevalence of obesity, insulin resistance and type 2 diabetes. In this, decreased rates of energy expenditure and impaired insulin...... and environmental background, the Trp64Arg polymorphism of the beta3AR gene is associated with lower fat mass, fasting insulin levels and an appropriate insulin response to glucose. Thus, heterozygosity for the Trp64Arg variant is unlikely to increase the risk of obesity, insulin resistance or type 2 diabetes....... secretion could play a role. METHODS: In 10 male twin pairs discordant for the Trp64Arg polymorphism, we examined insulin response to glucose by an oral glucose tolerance test (OGTT), a frequently sampled intravenous glucose tolerance test (FSIGT), body composition by the bioimpedance method, dual-energy X...

  6. Activation of Cyclic AMP Synthesis by Full and Partial Beta-Adrenergic Receptor Agonists in Chicken Skeletal Muscle Cells

    Science.gov (United States)

    Young, R. B.; Bridge, K. Y.

    2003-01-01

    Several beta-adrenergic receptor (bAR) agonists are known to cause hypertrophy of skeletal muscle tissue. Accordingly, five bAR agonists encompassing a range in activity from strong to weak were evaluated for their ability to stimulate CAMP accumulation in embryonic chicken skeletal muscle cells in culture. Two strong agonists (epinephrine and isoproterenol), one moderate agonist (albuterol), and two weak agonists known to cause hypertrophy in animals (clenbuterol and cimaterol) were studied. Dose response curves were determined over six orders of magnitude in concentration for each agonist, and values were determined for their maximum stimulation of CAMP synthesis rate (Bmax) and the agonist concentration at which 50% stimulation of CAMP synthesis (EC50) occurred. Bmax values decreased in the following order: isoproterenol, epinephrine, albuterol, cimaterol, clenbuterol. Cimaterol and clenbuterol at their Bmax concentrations were approximately 15-fold weaker than isoproterenol in stimulating the rate of CAMP synthesis. When cimaterol and clenbuterol were added to culture media at concentrations known to cause significant muscle hypertrophy in animals, there was no detectable effect on stimulation of CAMP synthesis. Finally, these same levels of cimaterol and clenbuterol did not antagonize the stimulation of CAMP by either epinephrine or isoproterenol.

  7. Haplotype structure of the beta2-adrenergic receptor gene in 814 Danish Caucasian subjects and association with body mass index

    DEFF Research Database (Denmark)

    Jensen, Mette Kamp; Nielsen, Morten; Koefoed, Pernille;

    2009-01-01

    .50-16.38). In conclusion, the haplotype analysis clearly revealed the prevalence of four major ADRB2 haplotypes in Caucasians. The results suggest that unique interactions in specific haplotype pairs rather than individual SNPs may affect BMI and that this effect of ADRB2 haplotypes is blunted by age-related factors.......Several single nucleotide polymorphisms (SNPs) have been identified in the beta(2)-adrenergic receptor gene (ADRB2). By the use of five SNPs (G46A, C79G, C491T, C523A, G1053C) for identification of ADRB2 haplotypes in 814 Danish Caucasians, we investigated whether ADRB2 haplotypes are associated...... with body mass index (BMI). The SNPs showed organization into 13 distinct haplotypes and 41 haplotype pairs. The study identified four common haplotypes: ACCCC (10.1 +/- 0.3 %), ACCCG (27.9 +/- 0.3 %), GCCAC (10.8 +/- 0.1 %) and GGCCG (41.0 +/- 0.2 %) (frequencies (SD), seen in 91 % of the population...

  8. Distinct effect of stress on 11beta-hydroxysteroid dehydrogenase type 1 and corticosteroid receptors in dorsal and ventral hippocampus.

    Science.gov (United States)

    Ergang, P; Kuželová, A; Soták, M; Klusoňová, P; Makal, J; Pácha, J

    2014-01-01

    Multiple lines of evidence suggest the participation of the hippocampus in the feedback inhibition of the hypothalamus-pituitary-adrenal axis during stress response. This inhibition is mediated by glucocorticoid feedback due to the sensitivity of the hippocampus to these hormones. The sensitivity is determined by the expression of glucocorticoid (GR) and mineralocorticoid (MR) receptors and 11beta-hydroxysteroid dehydrogenase type 1 (11HSD1), an enzyme that regulates the conversion of glucocorticoids from inactive to active form. The goal of our study was to assess the effect of stress on the expression of 11HSD1, GR and MR in the ventral and dorsal region of the CA1 hippocampus in three different rat strains with diverse responses to stress: Fisher 344, Lewis and Wistar. Stress stimulated 11HSD1 in the ventral but not dorsal CA1 hippocampus of Fisher 344 but not Lewis or Wistar rats. In contrast, GR expression following stress was decreased in the dorsal but not ventral CA1 hippocampus of all three strains. MR expression was not changed in either the dorsal or ventral CA1 region. These results indicate that (1) depending on the strain, stress stimulates 11HSD1 in the ventral hippocampus, which is known to be involved in stress and emotion reactions whereas (2) independent of strain, stress inhibits GR in the dorsal hippocampus, which is predominantly involved in cognitive functions.

  9. Single-cell TCRseq: paired recovery of entire T-cell alpha and beta chain transcripts in T-cell receptors from single-cell RNAseq.

    Science.gov (United States)

    Redmond, David; Poran, Asaf; Elemento, Olivier

    2016-01-01

    Accurate characterization of the repertoire of the T-cell receptor (TCR) alpha and beta chains is critical to understanding adaptive immunity. Such characterization has many applications across such fields as vaccine development and response, clone-tracking in cancer, and immunotherapy. Here we present a new methodology called single-cell TCRseq (scTCRseq) for the identification and assembly of full-length rearranged V(D)J T-cell receptor sequences from paired-end single-cell RNA sequencing reads. The method allows accurate identification of the V(D)J rearrangements for each individual T-cell and has the novel ability to recover paired alpha and beta segments. Source code is available at https://github.com/ElementoLab/scTCRseq . PMID:27460926

  10. The second Lilly Prize Lecture, University of Newcastle, July 1977. beta-Adrenergic receptor blockade in hypertension, past, present and future.

    Science.gov (United States)

    Prichard, B N

    1978-01-01

    All beta-adrenoceptor blocking drugs that have been described share the common property of being competitive inhibitors. They differ in their associated properties, the presence or absence of cardioselectivity, membrane stabilizing activity, and partial agonist activity. Recently some beta-adrenoceptor blocking drugs have been reported which also possess alpha-adrenoceptor blocking activity. The associated properties have been used as a basis for classifying beta-adrenoceptor blocking drugs (Fitzgerald, 1969, 1972). The presence or absence of cardioselectivity is most useful for dividing beta-adrenoceptor blocking drugs. The non-selective drugs (Division I) can be further divided according to the presence or absence of intrinsic sympathomimetic activity (ISA) and membrane stabilizing activity (Fitzgerald's groups I-IV). Group I possess both membrane activity and ISA, e.g. alprenolol, oxprenolol, group II just membrane action, e.g. propanolol, group III ISA but no membrane action, e.g. pindolol. Fitzgerald placed pindolol in group I but should be placed in group III as it possesses a high degree of beta-adrenoceptor blocking potency in relation to its membrane activity (Prichard, 1974). Finally drugs in group IV have neither ISA nor membrane action, e.g. sotalol, timolol. The cardioselective drugs (Division II) can be similarly sub-divided into groups I-IV according to the presence or absence of ISA or membrane action (Fitzgerald grouped all these together as group V). Lastly there are new beta-adrenergic receptor blocking drugs which in addition have alpha- adrenergic receptor blocking properties (Division III). PMID:26370

  11. The second Lilly Prize Lecture, University of Newcastle, July 1977. beta-Adrenergic receptor blockade in hypertension, past, present and future.

    Science.gov (United States)

    Prichard, B N

    1978-05-01

    All beta-adrenoceptor blocking drugs that have been described share the common property of being competitive inhibitors. They differ in their associated properties, the presence or absence of cardioselectivity, membrane stabilizing activity, and partial agonist activity. Recently some beta-adrenoceptor blocking drugs have been reported which also possess alpha-adrenoceptor blocking activity. The associated properties have been used as a basis for classifying beta-adrenoceptor blocking drugs (Fitzgerald, 1969, 1972). The presence or absence of cardioselectivity is most useful for dividing beta-adrenoceptor blocking drugs. The non-selective drugs (Division I) can be further divided according to the presence or absence of intrinsic sympathomimetic activity (ISA) and membrane stabilizing activity (Fitzgerald's groups I-IV). Group I possess both membrane activity and ISA, e.g. alprenolol, oxprenolol, group II just membrane action, e.g. propanolol, group III ISA but no membrane action, e.g. pindolol. Fitzgerald placed pindolol in group I but should be placed in group III as it possesses a high degree of beta-adrenoceptor blocking potency in relation to its membrane activity (Prichard, 1974). Finally drugs in group IV have neither ISA nor membrane action, e.g. sotalol, timolol. The cardioselective drugs (Division II) can be similarly sub-divided into groups I-IV according to the presence or absence of ISA or membrane action (Fitzgerald grouped all these together as group V). Lastly there are new beta-adrenergic receptor blocking drugs which in addition have alpha- adrenergic receptor blocking properties (Division III).

  12. Estrogen receptor beta and truncated variants enhance the expression of transfected MMP-1 promoter constructs in response to specific mechanical loading

    OpenAIRE

    Thaler, John D; Achari, Yamini; Lu, Ting; Shrive, Nigel G; Hart, David A.

    2014-01-01

    Background Joint diseases such as osteoarthritis (OA) predominantly afflict post-menopausal women, suggesting a pertinent role for female hormones. Estrogen receptor beta (ER-β) has been detected in connective tissues of the knee joint suggesting that these tissues are responsive to the hormone estrogen. Matrix metalloproteinase-1 (MMP-1) activity contributes to cartilage degradation, a key factor leading to OA development in synovial joints. Two polymorphic forms of MMP-1 exist due to a dele...

  13. Phosphatidylinositol 5-phosphate 4-kinase type II beta is required for vitamin D receptor-dependent E-cadherin expression in SW480 cells

    Energy Technology Data Exchange (ETDEWEB)

    Kouchi, Zen, E-mail: zkouchi@toyaku.ac.jp [Laboratory of Genome and Biosignals, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji-city, Tokyo 192-0392 (Japan); Fujiwara, Yuki [Laboratory of Genome and Biosignals, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji-city, Tokyo 192-0392 (Japan); Yamaguchi, Hideki [Division of Metastasis and Invasion Signaling, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045 (Japan); PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi-city, Saitama 332-0012 (Japan); Nakamura, Yoshikazu; Fukami, Kiyoko [Laboratory of Genome and Biosignals, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji-city, Tokyo 192-0392 (Japan)

    2011-05-20

    Highlights: {yields} We analyzed Phosphatidylinositol 5-phosphate kinase II{beta} (PIPKII{beta}) function in cancer. {yields} PIPKII{beta} is required for vitamin D receptor-mediated E-cadherin upregulation in SW480. {yields} PIPKII{beta} suppresses cellular motility through E-cadherin induction in SW480 cells. {yields} Nuclear PIP{sub 2} but not plasma membrane-localized PIP{sub 2} mediates E-cadherin upregulation. -- Abstract: Numerous epidemiological data indicate that vitamin D receptor (VDR) signaling induced by its ligand or active metabolite 1{alpha},25-dihydroxyvitamin D{sub 3} (1{alpha},25(OH){sub 2}D{sub 3}) has anti-cancer activity in several colon cancers. 1{alpha},25(OH){sub 2}D{sub 3} induces the epithelial differentiation of SW480 colon cancer cells expressing VDR (SW480-ADH) by upregulating E-cadherin expression; however, its precise mechanism remains unknown. We found that phosphatidylinositol-5-phosphate 4-kinase type II beta (PIPKII{beta}) but not PIPKII{alpha} is required for VDR-mediated E-cadherin induction in SW480-ADH cells. The syntenin-2 postsynaptic density protein/disc large/zona occludens (PDZ) domain and pleckstrin homology domain of phospholipase C-delta1 (PLC{delta}1 PHD) possess high affinity for phosphatidylinositol-4,5-bisphosphate (PI(4,5)P{sub 2}) mainly localized to the nucleus and plasma membrane, respectively. The expression of syntenin-2 PDZ but not PLC{delta}1 PHD inhibited 1{alpha},25(OH){sub 2}D{sub 3}-induced E-cadherin upregulation, suggesting that nuclear PI(4,5)P{sub 2} production mediates E-cadherin expression through PIPKII{beta} in a VDR-dependent manner. PIPKII{beta} is also involved in the suppression of the cell motility induced by 1{alpha},25(OH){sub 2}D{sub 3}. These results indicate that PIPKII{beta}-mediated PI(4,5)P{sub 2} signaling is important for E-cadherin upregulation and inhibition of cellular motility induced by VDR activation.

  14. The Pharmacology and Function of Receptors for Short-Chain Fatty Acids.

    Science.gov (United States)

    Bolognini, Daniele; Tobin, Andrew B; Milligan, Graeme; Moss, Catherine E

    2016-03-01

    Despite some blockbuster G protein-coupled receptor (GPCR) drugs, only a small fraction (∼ 15%) of the more than 390 nonodorant GPCRs have been successfully targeted by the pharmaceutical industry. One way that this issue might be addressed is via translation of recent deorphanization programs that have opened the prospect of extending the reach of new medicine design to novel receptor types with potential therapeutic value. Prominent among these receptors are those that respond to short-chain free fatty acids of carbon chain length 2-6. These receptors, FFA2 (GPR43) and FFA3 (GPR41), are each predominantly activated by the short-chain fatty acids acetate, propionate, and butyrate, ligands that originate largely as fermentation by-products of anaerobic bacteria in the gut. However, the presence of FFA2 and FFA3 on pancreatic β-cells, FFA3 on neurons, and FFA2 on leukocytes and adipocytes means that the biologic role of these receptors likely extends beyond the widely accepted role of regulating peptide hormone release from enteroendocrine cells in the gut. Here, we review the physiologic roles of FFA2 and FFA3, the recent development and use of receptor-selective pharmacological tool compounds and genetic models available to study these receptors, and present evidence of the potential therapeutic value of targeting this emerging receptor pair. PMID:26719580

  15. Modulatory effects of unsaturated fatty acids on the binding of glucocorticoids to rat liver glucocorticoid receptors.

    Science.gov (United States)

    Vallette, G; Vanet, A; Sumida, C; Nunez, E A

    1991-09-01

    Binding of the synthetic glucocorticoid dexamethasone to the rat liver cytosol glucocorticoid receptor was inhibited by physiological concentrations of nonesterified fatty acids as a function of increasing dose, degree of unsaturation, and chain length of the fatty acid. Polyunsaturated fatty acids were the most potent inhibitors. Scatchard analysis and Line-weaver-Burk plots of the binding data revealed that both the association constants and number of binding sites decreased and that polyunsaturated fatty acids inhibition was of a mixed non-competitive type. The dissociation rate constant of [3H]dexamethasone from glucocorticoid receptors was increased by up to 10 times in the presence of docosahexaenoic acid, whereas a competitive inhibitor like the glucocorticoid antagonist RU 38486 had no effect. Moreover, sucrose density gradient analysis showed that docosahexaenoic acid inhibited the binding of [3H] dexamethasone to both the 8.8S and 4S forms. The results strongly suggest that unsaturated fatty acids are interacting at a site on the receptor different from the hormone binding site and the heat shock protein and that by binding to a second site unsaturated fatty acids greatly change the conformation of the hormone binding site to reduce its affinity for the hormone, either partially or completely depending on the concentration and the class of the fatty acid. PMID:1874175

  16. Prediction of selective estrogen receptor beta agonist using open data and machine learning approach

    Science.gov (United States)

    Niu, Ai-qin; Xie, Liang-jun; Wang, Hui; Zhu, Bing; Wang, Sheng-qi

    2016-01-01

    Background Estrogen receptors (ERs) are nuclear transcription factors that are involved in the regulation of many complex physiological processes in humans. ERs have been validated as important drug targets for the treatment of various diseases, including breast cancer, ovarian cancer, osteoporosis, and cardiovascular disease. ERs have two subtypes, ER-α and ER-β. Emerging data suggest that the development of subtype-selective ligands that specifically target ER-β could be a more optimal approach to elicit beneficial estrogen-like activities and reduce side effects. Methods Herein, we focused on ER-β and developed its in silico quantitative structure-activity relationship models using machine learning (ML) methods. Results The chemical structures and ER-β bioactivity data were extracted from public chemogenomics databases. Four types of popular fingerprint generation methods including MACCS fingerprint, PubChem fingerprint, 2D atom pairs, and Chemistry Development Kit extended fingerprint were used as descriptors. Four ML methods including Naïve Bayesian classifier, k-nearest neighbor, random forest, and support vector machine were used to train the models. The range of classification accuracies was 77.10% to 88.34%, and the range of area under the ROC (receiver operating characteristic) curve values was 0.8151 to 0.9475, evaluated by the 5-fold cross-validation. Comparison analysis suggests that both the random forest and the support vector machine are superior for the classification of selective ER-β agonists. Chemistry Development Kit extended fingerprints and MACCS fingerprint performed better in structural representation between active and inactive agonists. Conclusion These results demonstrate that combining the fingerprint and ML approaches leads to robust ER-β agonist prediction models, which are potentially applicable to the identification of selective ER-β agonists. PMID:27486309

  17. A highly conserved phenylalanine in the alpha, beta-T cell receptor (TCR) constant region determines the integrity of TCR/CD3 complexes

    DEFF Research Database (Denmark)

    Caspar-Bauguil, S; Arnaud, J; Huchenq, A;

    1994-01-01

    In the present study, we have investigated the importance of a phenylalanine (phe195) in the Tcr-C alpha region on Tcr-alpha,beta/CD3 membrane expression. An exchange of phe195 with a tyrosine residue does not affect Tcr/CD3 membrane expression; however, exchange with aspartic acid, histidine...

  18. Design, synthesis, and structure-activity analysis of isoform-selective retinoic acid receptor ß ligands

    DEFF Research Database (Denmark)

    Lund, Birgitte W.; Knapp, Anne Eeg; Piu, Fabrice;

    2009-01-01

    We recently discovered the isoform selective RAR beta 2 ligand 4'-octyl-4-biphenylcarboxylic acid (3, AC-55649). Although 3 is highly potent at RAR beta 2 and displays excellent selectivity, solubility issues make it unsuitable for drug development. Herein we describe the exploration of the SAR in...

  19. Activation of the GLP-1 Receptor Signalling Pathway: A Relevant Strategy to Repair a Deficient Beta-Cell Mass

    Directory of Open Access Journals (Sweden)

    Bernard Portha

    2011-01-01

    Full Text Available Recent preclinical studies in rodent models of diabetes suggest that exogenous GLP-1R agonists and DPP-4 inhibitors have the ability to increase islet mass and preserve beta-cell function, by immediate reactivation of beta-cell glucose competence, as well as enhanced beta-cell proliferation and neogenesis and promotion of beta-cell survival. These effects have tremendous implication in the treatment of T2D because they directly address one of the basic defects in T2D, that is, beta-cell failure. In human diabetes, however, evidence that the GLP-1-based drugs alter the course of beta-cell function remains to be found. Several questions surrounding the risks and benefits of GLP-1-based therapy for the diabetic beta-cell mass are discussed in this review and require further investigation.

  20. Estrogen receptor alpha/beta ratio and estrogen receptor beta as predictors of endocrine therapy responsiveness–a randomized neoadjuvant trial comparison between anastrozole and tamoxifen for the treatment of postmenopausal breast cancer

    International Nuclear Information System (INIS)

    The role of estrogen receptor beta (ER-β) in breast cancer (BC) remains unclear. Some studies have suggested that ER-β may oppose the actions of estrogen receptor alpha (ER-α), and clinical evidence has indicated that the loss of ER-β expression is associated with a poor prognosis and resistance to endocrine therapy. The objective of the present study was to determine the role of ER-β and the ER-α/ER-β ratio in predicting the response to endocrine therapy and whether different regimens have any effect on ER-β expression levels. Ninety postmenopausal patients with primary BC were recruited for a short-term double-blinded randomized prospective controlled study. To determine tumor cell proliferation, we measured the expression of Ki67 in tumor biopsy samples taken before and after 26 days of treatment with anastrozole 1 mg/day (N = 25), tamoxifen 20 mg/day (N = 24) or placebo (N = 29) of 78 participants. The pre- and post-samples were placed in tissue microarray blocks and submitted for immunohistochemical assay. Biomarker statuses (ER-β, ER-α and Ki67) were obtained by comparing each immunohistochemical evaluation of the pre- and post-surgery samples using the semi-quantitative Allred’s method. Statistical analyses were performed using an ANOVA and Spearman’s correlation coefficient tests, with significance at p ≤ 0.05. The frequency of ER-β expression did not change after treatment (p = 0.33). There were no significant changes in Ki67 levels in ER-β-negative cases (p = 0.45), but in the ER-β-positive cases, the anastrozole (p = 0.01) and tamoxifen groups (p = 0.04) presented a significant reduction in post-treatment Ki67 scores. There was a weak but positive correlation between the ER-α and ER-β expression levels. Only patients with an ER-α/ER-β expression ratio between 1 and 1.5 demonstrated significant differences in Ki67 levels after treatment with anastrozole (p = 0.005) and tamoxifen (p = 0.026). Our results provide additional data that

  1. Structure and binding analysis of Polyporus squamosus lectin in complex with the Neu5Ac[alpha]2-6Gal[beta]1-4GlcNAc human-type influenza receptor

    Energy Technology Data Exchange (ETDEWEB)

    Kadirvelraj, Renuka; Grant, Oliver C.; Goldstein, Irwin J.; Winter, Harry C.; Tateno, Hiroaki; Fadda, Elisa; Woods, Robert J. (Michigan-Med); (NUI-Ireland); (Georgia)

    2013-03-07

    Glycan chains that terminate in sialic acid (Neu5Ac) are frequently the receptors targeted by pathogens for initial adhesion. Carbohydrate-binding proteins (lectins) with specificity for Neu5Ac are particularly useful in the detection and isolation of sialylated glycoconjugates, such as those associated with pathogen adhesion as well as those characteristic of several diseases including cancer. Structural studies of lectins are essential in order to understand the origin of their specificity, which is particularly important when employing such reagents as diagnostic tools. Here, we report a crystallographic and molecular dynamics (MD) analysis of a lectin from Polyporus squamosus (PSL) that is specific for glycans terminating with the sequence Neu5Ac{alpha}2-6Gal{beta}. Because of its importance as a histological reagent, the PSL structure was solved (to 1.7 {angstrom}) in complex with a trisaccharide, whose sequence (Neu5Ac{alpha}2-6Gal{beta}1-4GlcNAc) is exploited by influenza A hemagglutinin for viral adhesion to human tissue. The structural data illuminate the origin of the high specificity of PSL for the Neu5Ac{alpha}2-6Gal sequence. Theoretical binding free energies derived from the MD data confirm the key interactions identified crystallographically and provide additional insight into the relative contributions from each amino acid, as well as estimates of the importance of entropic and enthalpic contributions to binding.

  2. Effect of electrical stimulation on beta-adrenergic receptor population and cyclic amp production in chicken and rat skeletal muscle cell cultures

    Science.gov (United States)

    Young, R. B.; Bridge, K. Y.; Strietzel, C. J.

    2000-01-01

    Expression of the beta-adrenergic receptor (betaAR) and its coupling to cyclic AMP (cAMP) synthesis are important components of the signaling system that controls muscle atrophy and hypertrophy, and the goal of this study was to determine if electrical stimulation in a pattern simulating slow muscle contraction would alter the betaAR response in primary cultures of avian and mammalian skeletal muscle cells. Specifically, chicken skeletal muscle cells and rat skeletal muscle cells that had been grown for 7 d in culture were subjected to electrical stimulation for an additional 2 d at a pulse frequency of 0.5 pulses/sec and a pulse duration of 200 msec. In chicken skeletal muscle cells, the betaAR population was not significantly affected by electrical stimulation; however, the ability of these cells to synthesize cyclic AMP was reduced by approximately one-half. In contrast, the betaAR population in rat muscle cells was increased slightly but not significantly by electrical stimulation, and the ability of these cells to synthesize cyclic AMP was increased by almost twofold. The basal levels of intracellular cyclic AMP in neither rat muscle cells nor chicken muscle cells were affected by electrical stimulation.

  3. Melatonin reduces LH, 17 beta-estradiol and induces differential regulation of sex steroid receptors in reproductive tissues during rat ovulation

    Directory of Open Access Journals (Sweden)

    Pinheiro Patrícia Fernanda F

    2011-08-01

    Full Text Available Abstract Background Melatonin is associated with direct or indirect actions upon female reproductive function. However, its effects on sex hormones and steroid receptors during ovulation are not clearly defined. This study aimed to verify whether exposure to long-term melatonin is able to cause reproductive hormonal disturbances as well as their role on sex steroid receptors in the rat ovary, oviduct and uterus during ovulation. Methods Twenty-four adult Wistar rats, 60 days old (+/- 250 g were randomly divided into two groups. Control group (Co: received 0.9% NaCl 0.3 mL + 95% ethanol 0.04 mL as vehicle; Melatonin-treated group (MEL: received vehicle + melatonin [100 μg/100 g BW/day] both intraperitoneally during 60 days. All animals were euthanized by decapitation during the morning estrus at 4 a.m. Results Melatonin significantly reduced the plasma levels of LH and 17 beta-estradiol, while urinary 6-sulfatoximelatonin (STM was increased at the morning estrus. In addition, melatonin promoted differential regulation of the estrogen receptor (ER, progesterone receptor (PR, androgen receptor (AR and melatonin receptor (MTR along the reproductive tissues. In ovary, melatonin induced a down-regulation of ER-alpha and PRB levels. Conversely, it was observed that PRA and MT1R were up-regulated. In oviduct, AR and ER-alpha levels were down-regulated, in contrast to high expression of both PRA and PRB. Finally, the ER-beta and PRB levels were down-regulated in uterus tissue and only MT1R was up-regulated. Conclusions We suggest that melatonin partially suppress the hypothalamus-pituitary-ovarian axis, in addition, it induces differential regulation of sex steroid receptors in the ovary, oviduct and uterus during ovulation.

  4. Levels of 17beta-estradiol receptors expressed in embryonic and adult zebrafish following in vivo treatment of natural or synthetic ligands.

    Directory of Open Access Journals (Sweden)

    Gayathri Chandrasekar

    Full Text Available The nuclear receptors encompass a group of regulatory proteins involved in a number of physiological processes. The estrogen receptors (ERs, of which one alpha and one beta form exist in mammals function as transcription factors in response to 17beta-estradiol (E2. In zebrafish there are three gene products of estrogen receptors and they are denoted esr1 (ERalpha, esr2a (ERbeta2 and esr2b (ERbeta1. Total RNA of zebrafish early life stages (<3, 6, 12, 24, 48, 72, 96 and 120 hours post fertilization and of adult fish (liver, intestine, eye, heart, brain, ovary, testis, gill, swim bladder and kidney were isolated following in vivo exposures. Using specific primers for each of the three zebrafish ERs the expression levels were quantified using real time PCR methodology. It was shown that in absence of exposure all three estrogen receptors were expressed in adult fish. The levels of expression of two of these three ER genes, the esr1 and esr2a were altered in organs such as liver, intestine, brain and testis in response to ligand (E2, diethylstilbestrol or 4-nonylphenol. During embryogenesis two of the three receptor genes, esr1 and esr2b were expressed, and in presence of ligand the mRNA levels of these two genes increased. The conclusions are i estrogen receptor genes are expressed during early development ii altered expression of esr genes in response to ligand is dependent on the cellular context; iii the estrogenic ligand 4-nonylphenol, a manufactured compound commonly found in sewage of water treatment plants, acts as an agonist of the estrogen receptor during development and has both agonist and antagonist properties in tissues of adult fish. This knowledge of esr gene function in development and in adult life will help to understand mechanisms of interfering mimicking endocrine chemicals in vivo.

  5. Transforming growth factor beta receptor 2 (TGFBR2 changes sialylation in the microsatellite unstable (MSI Colorectal cancer cell line HCT116.

    Directory of Open Access Journals (Sweden)

    Jennifer Lee

    Full Text Available Aberrant glycosylation is a common feature of many malignancies including colorectal cancers (CRCs. About 15% of CRC show the microsatellite instability (MSI phenotype that is associated with a high frequency of biallelic frameshift mutations in the A10 coding mononucleotide microsatellite of the transforming growth factor beta receptor 2 (TGFBR2 gene. If and how impaired TGFBR2 signaling in MSI CRC cells affects cell surface glycan pattern is largely unexplored. Here, we used the TGFBR2-deficient MSI colon carcinoma cell line HCT116 as a model system. Stable clones conferring doxycycline (dox-inducible expression of a single copy wildtype TGFBR2 transgene were generated by recombinase-mediated cassette exchange (RMCE. In two independent clones, dox-inducible expression of wildtype TGFBR2 protein and reconstitution of its signaling function was shown. Metabolic labeling experiments using the tritiated sialic acid precursor N-acetyl-D-mannosamine (ManNAc revealed a significant decline (∼30% of its incorporation into newly synthesized sialoglycoproteins in a TGFBR2-dependent manner. In particular, we detected a significant decrease of sialylated ß1-integrin upon reconstituted TGFBR2 signaling which did not influence ß1-integrin protein turnover. Notably, TGFBR2 reconstitution did not affect the transcript levels of any of the known human sialyltransferases when examined by real-time RT- PCR analysis. These results suggest that reconstituted TGFBR2 signaling in an isogenic MSI cell line model system can modulate sialylation of cell surface proteins like ß1-integrin. Moreover, our model system will be suitable to uncover the underlying molecular mechanisms of altered MSI tumor glycobiology.

  6. Cytotoxic T-cells from T-cell receptor transgenic NOD8.3 mice destroy beta-cells via the perforin and Fas pathways.

    Science.gov (United States)

    Dudek, Nadine L; Thomas, Helen E; Mariana, Lina; Sutherland, Robyn M; Allison, Janette; Estella, Eugene; Angstetra, Eveline; Trapani, Joseph A; Santamaria, Pere; Lew, Andrew M; Kay, Thomas W H

    2006-09-01

    Cytotoxic T-cells are the major mediators of beta-cell destruction in type 1 diabetes, but the molecular mechanisms are not definitively established. We have examined the contribution of perforin and Fas ligand to beta-cell destruction using islet-specific CD8(+) T-cells from T-cell receptor transgenic NOD8.3 mice. NOD8.3 T-cells killed Fas-deficient islets in vitro and in vivo. Perforin-deficient NOD8.3 T-cells were able to destroy wild-type but not Fas-deficient islets in vitro. These results imply that NOD8.3 T-cells use both pathways and that Fas is required for beta-cell killing only when perforin is missing. Consistent with this theory, transgenic NOD8.3 mice with beta-cells that do not respond to Fas ligation were not protected from diabetes. We next investigated the mechanism of protection provided by overexpression of suppressor of cytokine signaling-1 (SOCS-1) in beta-cells of NOD8.3 mice. SOCS-1 islets remained intact when grafted into NOD8.3 mice and were less efficiently killed in vitro. However, addition of exogenous peptide rendered SOCS-1 islets susceptible to 8.3 T-cell-mediated lysis. Therefore, NOD8.3 T-cells use both perforin and Fas pathways to kill beta-cells and the surprising blockade of NOD8.3 T-cell-mediated beta-cell death by SOCS-1 overexpression may be due in part to reduced target cell recognition. PMID:16936188

  7. Phytanic acid and pristanic acid, branched-chain fatty acids associated with Refsum disease and other inherited peroxisomal disorders, mediate intracellular Ca2+ signaling through activation of free fatty acid receptor GPR40.

    Science.gov (United States)

    Kruska, Nicol; Reiser, Georg

    2011-08-01

    The accumulation of the two branched-chain fatty acids phytanic acid and pristanic acid is known to play an important role in several diseases with peroxisomal impairment, like Refsum disease, Zellweger syndrome and α-methylacyl-CoA racemase deficiency. Recent studies elucidated that the toxic activity of phytanic acid and pristanic acid is mediated by multiple mitochondrial dysfunctions, generation of reactive oxygen species and Ca2+ deregulation via the InsP3-Ca2+ signaling pathway in glial cells. However, the exact signaling mechanism through which both fatty acids mediate toxicity is still under debate. Here, we studied the ability of phytanic acid and pristanic acid to activate the free fatty acid receptor GPR40, a G-protein-coupled receptor, which was described to be involved in the Ca2+ signaling of fatty acids. We treated HEK 293 cells expressing the GPR40 receptor with phytanic acid or pristanic acid. This resulted in a significant increase in the intracellular Ca2+ level, similar to the effect seen after treatment with the synthetic GPR40 agonist GW9508. Furthermore, we demonstrate that the GPR40 activation might be due to an interaction of the carboxylate moiety of fatty acids with the receptor. Our findings indicate that the phytanic acid- and pristanic acid-mediated Ca2+ deregulation can involve the activation of GPR40. Therefore, we suppose that activation of GPR40 might be part of the signaling cascade of the toxicity of phytanic and pristanic acids.

  8. 9-cis-retinoic acid inhibits activation-driven T-cell apoptosis: implications for retinoid X receptor involvement in thymocyte development.

    OpenAIRE

    Yang, Y.; Vacchio, M S; Ashwell, J D

    1993-01-01

    Retinoic acid is a morphogenetic signaling molecule derived from vitamin A and involved in vertebrate development. Two groups of receptors, retinoic acid receptors and retinoid X receptors (RXRs), have been identified. All-trans-retinoic acid is the high-affinity ligand for retinoic acid receptors, and 9-cis-retinoic acid additionally binds RXRs with high affinity. Here we report that although retinoic acid has little inhibitory effect on activation-induced T-cell proliferation, it specifical...

  9. Unbinding of Retinoic Acid from its Receptor Studied by Steered Molecular Dynamics

    CERN Document Server

    Kosztin, D; Schulten, K; Kosztin, Dorina; Izrailev, Sergei; Schulten, Klaus

    1999-01-01

    Retinoic acid receptor (RAR) is a ligand-dependent transcription factor that regulates the expression of genes involved in cell growth, differentiation, and development. Binding of the retinoic acid hormone to RAR is accompanied by conformational changes in the protein which induce transactivation or transrepression of the target genes. In this paper we present a study of the hormone binding/unbinding process in order to clarify the role of some of the amino acid contacts and identify possible pathways of the all-trans retinoic acid binding/unbinding to/from human retinoic acid receptor (hRAR)-g. Three possible pathways were explored using steered molecular dynamics simulations. Unbinding was induced on a time scale of 1 ns by applying external forces to the hormone. The simulations suggest that the hormone may employ one pathway for binding and an alternative "back door" pathway for unbinding.

  10. Bovine adenovirus serotype 3 utilizes sialic acid as a cellular receptor for virus entry.

    Science.gov (United States)

    Li, Xiaoxin; Bangari, Dinesh S; Sharma, Anurag; Mittal, Suresh K

    2009-09-30

    Bovine adenovirus serotype 3 (BAd3) and porcine adenovirus serotype 3 (PAd3) entry into the host cells is independent of Coxsackievirus adenovirus receptor and integrins. The role of sialic acid in BAd3 and PAd3 entry was investigated. Removal of sialic acid by neuraminidase, or blocking sialic acid by wheat germ agglutinin lectin significantly inhibited BAd3, but not PAd3, transduction of Madin-Darby bovine kidney cells. Maackia amurensis agglutinin or Sambucus nigra (elder) agglutinin treatment efficiently blocked BAd3 transduction suggesting that BAd3 utilized alpha(2,3)-linked and alpha(2,6)-linked sialic acid as a cell receptor. BAd3 transduction of MDBK cells was sensitive to sodium periodate, bromelain, or trypsin treatment indicating that the receptor sialoconjugate was a glycoprotein rather than a ganglioside. To determine sialic acid-containing cell membrane proteins that bind to BAd3, virus overlay protein binding assay (VOPBA) was performed and showed that sialylated cell membrane proteins in size of approximately 97 and 34 kDa bind to BAd3. The results suggest that sialic acid serves as a primary receptor for BAd3.

  11. Bile Acids Induce Cdx2 Expression Through the Farnesoid X Receptor in Gastric Epithelial Cells

    OpenAIRE

    Xu, Yingji; Watanabe, Toshio; Tanigawa, Tetsuya; Machida, Hirohisa; Okazaki, Hirotoshi; Yamagami, Hirokazu; Watanabe, Kenji; Tominaga, Kazunari; Fujiwara, Yasuhiro; Oshitani, Nobuhide; Arakawa, Tetsuo

    2009-01-01

    Clinical and experimental studies showed that the reflux of bile into the stomach contributes to the induction of intestinal metaplasia of the stomach and gastric carcinogenesis. Caudal-type homeobox 2 (Cdx2) plays a key role in the exhibition of intestinal phenotypes by regulating the expression of intestine-specific genes such as goblet-specific gene mucin 2 (MUC2). We investigated the involvement of the farnesoid X receptor (FXR), a nuclear receptor for bile acids, in the chenodeoxycholic ...

  12. Bile acid-induced arrhythmia is mediated by muscarinic M2 receptors in neonatal rat cardiomyocytes.

    Directory of Open Access Journals (Sweden)

    Siti H Sheikh Abdul Kadir

    Full Text Available BACKGROUND: Intrahepatic cholestasis of pregnancy (ICP is a common disease affecting up to 5% of pregnancies and which can cause fetal arrhythmia and sudden intrauterine death. We previously demonstrated that bile acid taurocholate (TC, which is raised in the bloodstream of ICP, can acutely alter the rate and rhythm of contraction and induce abnormal calcium destabilization in cultured neonatal rat cardiomyocytes (NRCM. Apart from their hepatic functions bile acids are ubiquitous signalling molecules with diverse systemic effects mediated by either the nuclear receptor FXR or by a recently discovered G-protein coupled receptor TGR5. We aim to investigate the mechanism of bile-acid induced arrhythmogenic effects in an in-vitro model of the fetal heart. METHODS AND RESULTS: Levels of bile acid transporters and nuclear receptor FXR were studied by quantitative real time PCR, western blot and immunostaining, which showed low levels of expression. We did not observe functional involvement of the canonical receptors FXR and TGR5. Instead, we found that TC binds to the muscarinic M(2 receptor in NRCM and serves as a partial agonist of this receptor in terms of inhibitory effect on intracellular cAMP and negative chronotropic response. Pharmacological inhibition and siRNA-knockdown of the M(2 receptor completely abolished the negative effect of TC on contraction, calcium transient amplitude and synchronisation in NRCM clusters. CONCLUSION: We conclude that in NRCM the TC-induced arrhythmia is mediated by the partial agonism at the M(2 receptor. This mechanism might serve as a promising new therapeutic target for fetal arrhythmia.

  13. Identification of a Novel Non-retinoid Pan Inverse Agonist of the Retinoic Acid Receptors

    OpenAIRE

    Busby, Scott A.; Kumar, Naresh; Kuruvilla, Dana S.; Istrate, Monica A.; Conkright, Juliana J.; Wang, Yongjun; Kamenecka, Theodore M.; Cameron, Michael D.; Roush, William R.; Burris, Thomas P.; Griffin, Patrick R.

    2011-01-01

    Retinoids are potent forms of vitamin A and are involved in a broad range of physiological processes and the pharmacological effects of retinoids are primarily mediated by the retinoic acid receptors (RARs) and the retinoid X receptors (RXRs). Several natural and synthetic RAR modulators have proven to be clinically useful for a number of therapeutic indications including cancer, psoriasis, and diabetes. Unfortunately, these agents lead to a number of significant side effects. Most synthetic ...

  14. Comparison of sigma- and kappa-opiate receptor ligands as excitatory amino acid antagonists.

    OpenAIRE

    Berry, S. C.; Dawkins, S. L.; Lodge, D.

    1984-01-01

    Using the technique of microelectrophoresis in pentobarbitone-anaesthetized cats and rats, the effects of benzomorphans, with known actions at sigma- and kappa- opioid receptors, were tested on responses of spinal neurones to amino acids and acetylcholine. The racemic mixture and both enantiomers of the sigma opiate receptor agonist, N-allylnormetazocine (SKF 10, 047), and the dissociative anaesthetic, ketamine, reduced or abolished excitation evoked by N-methyl-aspartate (NMA) with only smal...

  15. Factors affecting the interactions between beta-lactoglobulin and fatty acids as revealed in molecular dynamics simulations.

    Science.gov (United States)

    Yi, Changhong; Wambo, Thierry O

    2015-09-21

    Beta-lactoglobulin (BLG), a bovine dairy protein, is a promiscuously interacting protein that can bind multiple hydrophobic ligands. Fatty acids (FAs), common hydrophobic molecules bound to BLG, are important sources of fuel for life because they yield large quantities of ATP when metabolized. The binding affinity increases with the length of the ligands, indicating the importance of the van der Waals (vdW) interactions between the hydrocarbon tail and the hydrophobic calyx of BLG. An exception to this rule is caprylic acid (OCA) which is two-carbon shorter but has a stronger binding affinity than capric acid. Theoretical calculations in the current literature are not accurate enough to shed light on the underlying physics of this exception. The computed affinity values are greater for longer fatty acids without respect for the caprylic exception and those values are generally several orders of magnitude away from the experimental data. In this work, we used hybrid steered molecular dynamics to accurately compute the binding free energies between BLG and the five saturated FAs of 8 to 16 carbon atoms. The computed binding free energies agree well with experimental data not only in rank but also in absolute values. We gained insights into the exceptional behavior of caprylic acid in the computed values of entropy and electrostatic interactions. We found that the electrostatic interaction between the carboxyl group of caprylic acid and the two amino groups of K60/69 in BLG is much stronger than the vdW force between the OCA's hydrophobic tail and the BLG calyx. This pulls OCA to the top of the beta barrel where it is easier to fluctuate, giving rise to greater entropy of OCA at the binding site. PMID:26272099

  16. A mollusk retinoic acid receptor (RAR) ortholog sheds light on the evolution of ligand binding.

    Science.gov (United States)

    Gutierrez-Mazariegos, Juliana; Nadendla, Eswar Kumar; Lima, Daniela; Pierzchalski, Keely; Jones, Jace W; Kane, Maureen; Nishikawa, Jun-Ichi; Hiromori, Youhei; Nakanishi, Tsuyoshi; Santos, Miguel M; Castro, L Filipe C; Bourguet, William; Schubert, Michael; Laudet, Vincent

    2014-11-01

    Nuclear receptors are transcription factors that regulate networks of target genes in response to small molecules. There is a strong bias in our knowledge of these receptors because they were mainly characterized in classical model organisms, mostly vertebrates. Therefore, the evolutionary origins of specific ligand-receptor couples still remain elusive. Here we present the identification and characterization of a retinoic acid receptor (RAR) from the mollusk Nucella lapillus (NlRAR). We show that this receptor specifically binds to DNA response elements organized in direct repeats as a heterodimer with retinoid X receptor. Surprisingly, we also find that NlRAR does not bind all-trans retinoic acid or any other retinoid we tested. Furthermore, NlRAR is unable to activate the transcription of reporter genes in response to stimulation by retinoids and to recruit coactivators in the presence of these compounds. Three-dimensional modeling of the ligand-binding domain of NlRAR reveals an overall structure that is similar to vertebrate RARs. However, in the ligand-binding pocket (LBP) of the mollusk receptor, the alteration of several residues interacting with the ligand has apparently led to an overall decrease in the strength of the interaction with the ligand. Accordingly, mutations of NlRAR at key positions within the LBP generate receptors that are responsive to retinoids. Altogether our data suggest that, in mollusks, RAR has lost its affinity for all-trans retinoic acid, highlighting the evolutionary plasticity of its LBP. When put in an evolutionary context, our results reveal new structural and functional features of nuclear receptors validated by millions of years of evolution that were impossible to reveal in model organisms. PMID:25116705

  17. Metabolism of ricinoleic acid into gamma-decalactone: beta-oxidation and long chain acyl intermediates of ricinoleic acid in the genus Sporidiobolus sp.

    Science.gov (United States)

    Blin-Perrin, C; Molle, D; Dufosse, L; Le-Quere, J L; Viel, C; Mauvais, G; Feron, G

    2000-07-01

    In order to study differences in gamma-decalactone production in yeast, four species of Sporidiobolus were cultivated with 5% of methyl ricinoleate as the lactone substrate. In vivo studies showed different time courses of intermediates of ricinoleic acid breakdown between the four species. In vitro studies of the beta-oxidation system were conducted with crude cell extracts of Sporidiobolus spp. and with ricinoleyl-CoA (RCoA) as substrate. The beta-oxidation was detected by measuring acyl-CoA oxidase, 3-hydroxyacyl-CoA dehydrogenase activities, and acetyl-CoA production. The time courses of the CoA esters resulting from RCoA breakdown by crude extract of Sporidiobolus spp. permit the proposal of different metabolic models in the yeast. These models explained the differences observed during in vivo studies. PMID:10867236

  18. N-Hydroxypyrazolyl glycine derivatives as selective N-methyl-D-aspartic acid receptor ligands

    DEFF Research Database (Denmark)

    Clausen, Rasmus Prætorius; Christensen, Caspar; Hansen, Kasper Bø;

    2008-01-01

    glycine (NHP5G) derivatives are selectively recognized by N-methyl- d-aspartic acid (NMDA) receptors and that the ( R)-enantiomers are preferred. Moreover, several of the compounds are able to discriminate between individual subtypes among the NMDA receptors, providing new pharmacological tools. For......A series of analogues based on N-hydroxypyrazole as a bioisostere for the distal carboxylate group of aspartate have been designed, synthesized, and pharmacologically characterized. Affinity studies on the major glutamate receptor subgroups show that these 4-substituted N-hydroxypyrazol-5-yl...

  19. Metabolism meets immunity: the role of free fatty acid receptors in the immune system

    OpenAIRE

    Alvarez-Curto, Elisa; Milligan, Graeme

    2016-01-01

    There are significant numbers of nutrient sensing G protein-coupled receptors (GPCRs) that can be found in cells of the immune system and in tissues that are involved in metabolic function, such as the pancreas or the intestinal epithelium. The family of free fatty acid receptors (FFAR1-4, GPR84), plus a few other metabolite sensing receptors (GPR109A, GPR91, GPR35) have been for this reason the focus of studies linking the effects of nutrients with immunological responses. A number of the be...

  20. Function of retinoic acid receptors during embryonic development.

    OpenAIRE

    Mark, Manuel; Ghyselinck, Norbert; Chambon, Pierre

    2009-01-01

    International audience Retinoids, the active metabolites of vitamin A, regulate complex gene networks involved in vertebrate morphogenesis, growth, cellular differentiation and homeostasis. Studies performed in vitro, using either acellular systems or transfected cells, have shown that retinoid actions are mediated through heterodimers between the RAR and RXR nuclear receptors. However, in vitro studies indicate what is possible, but not necessarily what is actually occurring in vivo, beca...