Sample records for acid receptor beta

  1. Differential modulation of alpha 3 beta 2 and alpha 3 beta 4 neuronal nicotinic receptors expressed in Xenopus oocytes by flufenamic acid and niflumic acid. (United States)

    Zwart, R; Oortgiesen, M; Vijverberg, H P


    Effects of flufenamic acid (FFA) and niflumic acid (NFA), which are often used to block Ca(2+)-activated Cl- current, have been investigated in voltage-clamped Xenopus oocytes expressing alpha 3 beta 2 and alpha 3 beta 4 nicotinic ACh receptors (nAChRs). NFA and FFA inhibit alpha 3 beta 2 nAChR-mediated inward currents and potentiate alpha 3 beta 4 nAChR-mediated inward currents in normal, Cl(-)-free and Ca(2+)-free solutions to a similar extent. The concentration-dependence of the inhibition of alpha 3 beta 2 nAChR-mediated ion current yields IC50 values of 90 microM for FFA and of 260 microM for NFA. The potentiation of alpha 3 beta 4 nAChR-mediated ion current by NFA yields an EC50 value of 30 microM, whereas the effect of FFA does not saturate for concentrations of up to 1 mM. At 100 microM, FFA reduces the maximum of the concentration-effect curve of ACh for alpha 3 beta 2 nAChRs, but leaves the EC50 of ACh unaffected. The same concentration of FFA potentiates alpha 3 beta 4 nAChR-mediated ion currents for all ACh concentrations and causes a small shift of the concentration-effect curve of ACh to lower agonist concentrations. The potentiation, like the inhibition, is most likely due to a noncompetitive effect of FFA. Increasing ACh-induced inward current either by raising the agonist concentration from 10 microM to 200 microM or by coapplication of 10 microM ACh and 200 microM FFA causes a similar enhancement of block of the alpha 3 beta 4 nAChR-mediated ion current by Mg2+. This suggests that the effects of FFA and of an increased agonist concentration result in a similar functional modification of the alpha 3 beta 4 nAChR-operated ion channel. It is concluded that alpha 3 beta 4 and alpha 3 beta 2 nAChRs are oppositely modulated by FFA and NFA through a direct beta-subunit-dependent effect.

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

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    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: [Department of Physiology and Biophysics, Virginia Commonwealth University School of Medicine, Richmond, VA (United States); Sanyal, Arun J., E-mail: [Division of Gastroenterology, Hepatology and Nutrition, Department of Internal Medicine, Virginia Commonwealth University School of Medicine, Richmond, VA (United States)


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


    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.

  4. 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

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


    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.

  5. Interleukin-1beta but not tumor necrosis factor-alpha potentiates neuronal damage by quinolinic acid: protection by an adenosine A2A receptor antagonist. (United States)

    Stone, Trevor W; Behan, Wilhelmina M H


    Quinolinic acid is an agonist at glutamate receptors sensitive to N-methyl-D-aspartate (NMDA). It has been implicated in neural dysfunction associated with infections, trauma, and ischemia, although its neurotoxic potency is relatively low. This study was designed to examine the effects of a combination of quinolinic acid and the proinflammatory cytokines interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha). Compounds were administered to the hippocampus of anesthetized male rats, animals being allowed to recover for 7 days before histological analysis of the hippocampus for neuronal damage estimated by counting of intact, healthy neurons. A low dose of quinolinic acid or IL-1beta produced no damage by itself, but the two together induced a significant loss of pyramidal neurons in the hippocampus. Higher doses produced almost total loss of pyramidal cells. Intrahippocampal TNF-alpha produced no effect alone but significantly reduced the neuronal loss produced by quinolinic acid. The adenosine A(2A) receptor antagonist ZM241385 reduced neuronal loss produced by the combinations of quinolinic acid and IL-1beta. The results suggest that simultaneous quinolinic acid and IL-1beta, both being induced by cerebral infection or injury, are synergistic in the production of neuronal damage and could together contribute substantially to traumatic, infective, or ischemic cerebral damage. Antagonism of adenosine A(2A) receptors protects neurons against the combination of quinolinic acid and IL-1beta.

  6. 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. (United States)

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


    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.

  7. Vitamin A increases nerve growth factor and retinoic acid receptor beta and improves diabetic neuropathy in rats. (United States)

    Hernández-Pedro, Norma; Granados-Soto, Vinicio; Ordoñez, Graciela; Pineda, Benjamin; Rangel-López, Edgar; Salazar-Ramiro, Aleli; Arrieta, Oscar; Sotelo, Julio


    All-trans retinoic acid (ATRA) promotes the endogenous expression of both nerve growth factor (NGF) and retinoic acid receptor beta (RAR-β). We have previously shown that the administration of ATRA partly reverts the damage induced by diabetic neuropathy (DN). In this investigation, we evaluated the effects of vitamin A, a commercial, inexpensive compound of retinoic acid, on the therapy of DN. A total of 70 rats were randomized into 4 groups. Group A was the control, and groups B, C, and D received a total dose of 60 mg/kg streptozotocin intraperitoneally. When signs of DN developed, groups C and D were treated either with vitamin A (20,000 IU) or with ATRA 25 mg/kg for 60 days. Plasma glucose, contents of NGF, thermal and nociceptive tests, and RAR-β expression were evaluated. All diabetic rats developed neuropathy. The treatment with vitamin A and ATRA reverted similarly the sensorial disturbances, which was associated with increased contents of NGF and RAR-β expression. Our results indicate that the administration of vitamin A has the same therapeutic effect as ATRA on peripheral neuropathy and suggest its potential therapeutic use in patients with diabetes.

  8. Positive regulation of the peroxisomal beta-oxidation pathway by fatty acids through activation of peroxisome proliferator-activan>ated receptors (PPAR). (United States)

    Dreyer, C; Keller, H; Mahfoudi, A; Laudet, V; Krey, G; Wahli, W


    Peroxisome proliferators regulate the transcription of genes by activating ligand-dependent transcription factors, which, due to their structure and function, can be assigned to the superfamily of nuclear hormone receptors. Three such peroxisome proliferator-activan>ated receptors (PPAR alpha, beta, and gamma) have been cloned in Xenopus laevis. Their mRNAs are expressed differentially; xPPAR alpha and beta but not xPPAR gamma are expressed in oocytes and embryos. In the adult, expression of xPPAR alpha and beta appears to be ubiquitous, and xPPAR gamma is mainly observed in adipose tissue and kidney. Immunocytochemical analysis revealed that PPARs are nuclear proteins, and that their cytoplasmic-nuclear translocation is independent of exogenous activators. A target gene of PPARs is the gene encoding acyl-CoA oxidase (ACO), which catalyzes the rate-limiting step in the peroxisomal beta-oxidation of fatty acids. A peroxisome proliferator response element (PPRE), to which PPARs bind, has been identified within the promoter of the ACO gene. Besides the known xenobiotic activators of PPARs, such as hypolipidemic drugs, natural activators have been identified. Polyunsaturated fatty acids at physiological concentrations are efficient activators of PPARs, and 5,8,11,14-eicosatetraynoic acid (ETYA), which is the alkyne homolog of arachidonic acid, is the most potent activator of xPPAR alpha described to date. Taken together, our data suggest that PPARs have an important role in lipid metabolism.

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

    Wagoner, Kelly R; Czajkowski, Cynthia


    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.

  10. Serotonin Transporter (5-HTT) and gamma-Aminobutyric Acid Receptor Subunit beta3 (GABRB3) Gene Polymorphisms are not Associated with Autism in the IMGSA Families

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    Maestrini, E.; Lai, C.; Marlow, A.;


    Previous studies have suggested that the serotonin transporter (5-HTT) gene and the gamma-aminobutyric acid receptor subunit beta3 (GABRB3) gene, or other genes in the 15q11-q13 region, are possibly involved in susceptibility to autism. To test this hypothesis we performed an association study...... and the GABRB3 genes are unlikely to play a major role in the aetiology of autism in our family data set....

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

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


    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.

  12. A retinoic acid receptor beta agonist (CD2019) overcomes inhibition of axonal outgrowth via phosphoinositide 3-kinase signalling in the injured adult spinal cord. (United States)

    Agudo, Marta; Yip, Ping; Davies, Meirion; Bradbury, Elizabeth; Doherty, Patrick; McMahon, Stephen; Maden, Malcolm; Corcoran, Jonathan P T


    After spinal cord injury in the adult mammal, axons do not normally regrow and this commonly leads to paralysis. Retinoic acid (RA) can stimulate neurite outgrowth in vitro of both the embryonic central and peripheral nervous system, via activation of the retinoic acid receptor (RAR) beta2. We show here that regions of the adult CNS, including the cerebellum and cerebral cortex, express RARbeta2. We show that when cerebellar neurons are grown in the presence of myelin-associated glycoprotein (MAG) which inhibits neurite outgrowth, RARbeta can be activated in a dose dependent manner by a RARbeta agonist (CD2019) and neurite outgrowth can occur via phosphoinositide 3-kinase (PI3K) signalling. In a model of spinal cord injury CD2019 also acts through PI3K signalling to induce axonal outgrowth of descending corticospinal fibres and promote functional recovery. Our data suggest that RARbeta agonists may be of therapeutic potential for human spinal cord injuries.

  13. Beta adrenergic receptors in human cavernous tissue

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    Dhabuwala, C.B.; Ramakrishna, C.V.; Anderson, G.F.


    Beta adrenergic receptor binding was performed with /sup 125/I iodocyanopindolol on human cavernous tissue membrane fractions from normal tissue and transsexual procedures obtained postoperatively, as well as from postmortem sources. Isotherm binding studies on normal fresh tissues indicated that the receptor density was 9.1 fmoles/mg. with a KD of 23 pM. Tissue stored at room temperature for 4 to 6 hours, then at 4C in saline solution for 19 to 20 hours before freezing showed no significant changes in receptor density or affinity, and provided evidence for the stability of postmortem tissue obtained within the same time period. Beta receptor density of 2 cavernous preparations from transsexual procedures was not significantly different from normal control tissues, and showed that high concentrations of estrogen received by these patients had no effect on beta adrenergic receptor density. Displacement of /sup 125/iodocyanopindolol by 5 beta adrenergic agents demonstrated that 1-propranolol had the greatest affinity followed by ICI 118,551, zinterol, metoprolol and practolol. When the results of these displacement studies were subjected to Scatfit, non- linear regression line analysis, a single binding site was described. Based on the relative potency of the selective beta adrenergic agents it appears that these receptors were of the beta 2 subtype.

  14. 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


    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.

  15. Inhibitory effect of acetyl-11-keto-beta-boswellic acid on androgen receptor by interference of Sp1 binding activity in prostate cancer cells. (United States)

    Yuan, Hui-Qing; Kong, Feng; Wang, Xiao-Ling; Young, Charles Y F; Hu, Xiao-Yan; Lou, Hong-Xiang


    Androgen receptor (AR)-mediated signaling is crucial for the development and progression of prostate cancer (PCa). Naturally occurring phytochemicals that target the AR signaling offer significant protection against this disease. Acetyl-11-keto-beta-boswellic acid (AKBA), a compound isolated from the gum-resin of Boswellia carterii, caused G1-phase cell cycle arrest with an induction of p21(WAF1/CIP1), and a reduction of cyclin D1 as well in prostate cancer cells. AKBA-mediated cellular proliferation inhibition was associated with a decrease of AR expression at mRNA and protein levels. Furthermore, the functional biomarkers used in evaluation of AR transactivity showed suppressions of prostate-specific antigen promoter-dependent and androgen responsive element-dependent luciferase activities. Additionally, down-regulation of an AR short promoter mainly containing a Sp1 binding site suggested the essential role of Sp1 for the reduction of AR expression in cells exposed to AKBA. Interruption effect of AKBA on Sp1 binding activity but not Sp1 protein levels was further confirmed by EMSA and transient transfection with a luciferase reporter driven by three copies of the Sp1 binding site of the AR promoter. Therefore, anti-AR properties ascribed to AKBA suggested that AKBA-containing drugs could be used for the development of novel therapeutic chemicals.

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


    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.

  18. Allosteric modulation of alpha4beta2 nicotinic acetylcholine receptors by HEPES. (United States)

    Weltzin, Maegan M; Huang, Yanzhou; Schulte, Marvin K


    A number of new positive allosteric modulators (PAMs) have been reported that enhance responses of neuronal alpha7 and alpha4beta2 nicotinic acetylcholine receptor subtypes to orthosteric ligands. PAMs represent promising new leads for the development of therapeutic agents for disorders involving alterations in nicotinic neurotransmission including Autism, Alzheimer's and Parkinson's disease. During our recent studies of alpha4beta2 PAMs, we identified a novel effect of 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES). The effects of HEPES were evaluated in a phosphate buffered recording solution using two-electrode voltage clamp techniques and alpha4beta2 and alpha7 nicotinic acetylcholine receptor subtypes expressed in Xenopus laevis oocytes. Acetylcholine induced responses of high-sensitivity alpha4beta2 receptors were potentiated 190% by co-exposure to HEPES. Responses were inhibited at higher concentrations (bell-shaped concentration/response curve). Coincidentally, at concentrations of HEPES typically used in oocyte recording (5-10mM), the potentiating effects of HEPES are matched by its inhibitory effects, thus producing no net effect. Mutagenesis results suggest HEPES potentiates the high-sensitivity stoichiometry of the alpha4beta2 receptors through action at the beta2+/beta2- interface and is dependent on residue beta2D218. HEPES did not potentiate low-sensitivity alpha4beta2 receptors and did not produce any observable effect on acetylcholine induced responses on alpha7 nicotinic acetylcholine receptors.

  19. Role of human GABA(A) receptor beta3 subunit in insecticide toxicity. (United States)

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


    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.

  20. Monitoring of beta-receptor sensitivity in cardiac surgery

    DEFF Research Database (Denmark)

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


    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.......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....

  1. Signaling from beta1- and beta2-adrenergic receptors is defined by differential interactions with PDE4

    DEFF Research Database (Denmark)

    Richter, Wito; Day, Peter; Agrawal, Rani


    Beta1- and beta2-adrenergic receptors (betaARs) are highly homologous, yet they play clearly distinct roles in cardiac physiology and pathology. Myocyte contraction, for instance, is readily stimulated by beta1AR but not beta2AR signaling, and chronic stimulation of the two receptors has opposing...

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

    DEFF Research Database (Denmark)

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


    crystallization, we engineered a beta2AR fusion protein in which T4 lysozyme (T4L) replaces most of the third intracellular loop of the GPCR ("beta2AR-T4L") and showed that this protein retains near-native pharmacologic properties. Analysis of adrenergic receptor ligand-binding mutants within the context...... 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...

  3. [Beta-3 adrenergic receptor--structure and role in obesity and metabolic disorders]. (United States)

    Wiejak, J; Wyroba, E


    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.

  4. Dynamin-association with agonist-mediated sequestration of beta-adrenergic receptor in single-cell eukaryote Paramecium. (United States)

    Wiejak, Jolanta; Surmacz, Liliana; Wyroba, Elzbieta


    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:

  5. Inhibition of human and rat 11beta-hydroxysteroid dehydrogenase type 1 by 18beta-glycyrrhetinic acid derivatives. (United States)

    Su, Xiangdong; Vicker, Nigel; Lawrence, Harshani; Smith, Andrew; Purohit, Atul; Reed, Michael J; Potter, Barry V L


    11beta-Hydroxysteroid dehydrogenase type 1 (11beta-HSD1) plays an important role in regulating the cortisol availability to bind to corticosteroid receptors within specific tissue. Recent advances in understanding the molecular mechanisms of metabolic syndrome indicate that elevation of cortisol levels within specific tissues through the action of 11beta-HSD1 could contribute to the pathogenesis of this disease. Therefore, selective inhibitors of 11beta-HSD1 have been investigated as potential treatments for metabolic diseases, such as diabetes mellitus type 2 or obesity. Here we report the discovery and synthesis of some 18beta-glycyrrhetinic acid (18beta-GA) derivatives (2-5) and their inhibitory activities against rat hepatic11beta-HSD1 and rat renal 11beta-HSD2. Once the selectivity over the rat type 2 enzyme was established, these compounds' ability to inhibit human 11beta-HSD1 was also evaluated using both radioimmunoassay (RIA) and homogeneous time resolved fluorescence (HTRF) methods. The 11-modified 18beta-GA derivatives 2 and 3 with apparent selectivity for rat 11beta-HSD1 showed a high percentage inhibition for human microsomal 11beta-HSD1 at 10 microM and exhibited IC50 values of 400 and 1100 nM, respectively. The side chain modified 18beta-GA derivatives 4 and 5, although showing selectivity for rat 11beta-HSD1 inhibited human microsomal 11beta-HSD1 with IC50 values in the low micromolar range.

  6. Brain beta-adrenergic receptor binding in rats with obesity induced by a beef tallow diet. (United States)

    Matsuo, T; Suzuki, M


    We have previously reported that compared with safflower oil diet, feeding a beef tallow diet leads to a greater accumulation of body fat by reducing sympathetic activities. The present study examined the effects of dietary fats consisting of different fatty acids on alpha1- and beta-adrenergic receptor binding in the hypothalamus and cerebral cortex. Male Sprague-Dawley rats were meal-fed isoenergetic diets based on safflower oil (rich in n-6 polyunsaturated fatty acids) or beef tallow (rich in saturated fatty acids) for 8 weeks. Binding affinities of the beta-adrenergic receptor in the hypothalamus and cortex were significantly lower in the beef tallow diet group, but those of the alpha1-receptor did not differ between the two groups. The polyunsaturated to saturated fatty acid (P/S) ratio and fluidities of plasma membranes in the hypothalamus and cortex were lower in the beef tallow diet group than in the safflower oil diet group. These results suggest that the beef tallow diet decreases membrane fluidity by altering the fatty acid composition of plasma membranes in the hypothalamus and cerebral cortex of rat. Consequently, beta-adrenergic receptor binding affinities in the brain were lower in rats fed the beef tallow diet than in rats fed the safflower oil diet. We recognized that there is possible link between the membrane fluidity and the changes in affinity of beta-adrenoceptors in rat brain.

  7. 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


    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.

  8. [Beta 3 adrenergic receptor polymorphism and obesity]. (United States)

    Yoshida, T; Umekawa, T


    The beta 3-adrenoceptor plays a significant role in the control of lipolysis and thermogenesis in the brown adipose tissue of rodents and humans. In human beta 3-adrenoceptor, a Trp to Arg replacement has recently been discovered. This change which occurs at position 64, in the first coding exon, has been correlated with increased weight gain, difficulty in losing weight, insulin resistance syndrome, and worsened diabetic situation. Higher percentages of this mutation are observed in Pima Indians (over 30%) and Japanese (20%). The possible functional mechanism of Trp54Arg is reported using human HEK293 cell line stably expressing the wild type and the [Arg64] beta 3-adrenoceptor type. Beta 3-adrenoceptor agonists available for humans are been also developing. In this paper we describe these points up-to-date.

  9. Homology modeling of human alpha 1 beta 2 gamma 2 and house fly beta 3 GABA receptor channels and Surflex-docking of fipronil. (United States)

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


    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.

  10. Studies on the metabolism of beta-hydroxy- aspartic acid

    Directory of Open Access Journals (Sweden)



    Full Text Available The content of beta-hydroxyaspartic acid was measured in the urine of man and several species of animals. The configuration of urinary beta-hydroxyaspartic acid was deduced to be L-erythro in form by chromatographic comparisons with authentic samples. An increased excretion of urinary beta-hydroxyaspartic acid was observed in cats when serine or thiamine was administered with glycine. Glycine-1-14C administered to rats was incorporated into the urinary beta-hydroxyaspartic acid. The formation of beta-hydroxyaspartic acid in pig-liver homogenate increased in the presence of glutamate and thiamine pyrophosphate. These results were discussed in relation to the author's working hypothesis on the biosynthesis of beta-hydroxyaspartic acid.

  11. Changes of lymphocyte beta-adrenergic receptors after surgical stress. (United States)

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


    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.

  12. The pharmacology of spontaneously open alpha 1 beta 3 epsilon GABA A receptor-ionophores. (United States)

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


    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.

  13. 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:


    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.

  14. 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


    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.

  15. Salvianolic Acid B inhibits platelet adhesion under conditions of flow by a mechanism involving the collagen receptor alpha 2 beta 1

    NARCIS (Netherlands)

    Wu, Ya Ping; Zhao, Xiao Min; Pan, Shao Dong; Guo, De An; Wei, Ran; Han, Ji Ju; Kainoh, Mie; Xia, Zuo Li; de Groot, Philip G.; Lisman, Ton


    Salvianolic acid B (SAB) is a component of Danshen, a herb widely used in Chinese medicine, and was previously shown to exert a number of biological activities including inhibition of platelet function, but the exact mechanisms involved are unclear. SAB dose-dependently inhibited platelet deposition

  16. Excitatory amino acid receptor antagonists

    DEFF Research Database (Denmark)

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


    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...

  17. Biological significance of glucocorticoid receptor beta

    Institute of Scientific and Technical Information of China (English)


    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

  18. Estrogen receptor beta agonists in neurobehavioral investigations. (United States)

    Choleris, Elena; Clipperton, Amy E; Phan, Anna; Kavaliers, Martin


    Neurobehavioral investigations into the functions of estrogen receptor (ER)alpha and ERbeta have utilized 'knockout' mice, phytoestrogens and, more recently, ER-specific agonists. Feeding, sexual, aggressive and social behavior, anxiety, depression, drug abuse, pain perception, and learning (and associated synaptic plasticity) are affected by ERalpha and ERbeta in a manner that is dependent upon the specific behavior studied, gender and developmental stage. Overall, ERalpha and ERbeta appear to function together to foster sociosexual behavior while inhibiting behaviors that, if occurring at the time of behavioral estrous, may compete with reproduction (eg, feeding). Recently developed pharmacological tools have limited selectivity and availability to the research community at large, as they are not commercially available. The development of highly selective, commercially available ERbeta-specific antagonists would greatly benefit preclinical and applied research.

  19. [Functional analysis of transforming growth factor-beta type II dominant negative receptor]. (United States)

    Takarada, M


    The transforming growth factor-beta (TGF-beta) is a multifunctional homodimeric protein with an apparent molecular weight of 25 KDa. TGF-beta transduces signals by forming heteromeric complexes of their type-I (T beta R-I) and type-II (T beta R-II) serin/threonine kinase receptors. TGF-beta binds first to T beta R-II receptor, and then the ligand in this complex is recognized by T beta R-I, resulting in formation of a heteromeric receptor complex composed of T beta R-I and T beta R-II. Once received, T beta R-I becomes phosphorylated in the GS domain by the associated constitutively active T beta R-II and transmits the downstream signal. It has been reported that formation of the heteromeric complex is indispensible at least in epithelial cells for growth inhibition and extracellular matrix production induced by TGF-beta. In this study, the functional role of T beta R-II for the TGF-beta-induced signals in osteoblastic cells was investigated by using a dominant negative type of T beta R-II mutant receptors (T beta RIIDNR). ROS 17/2.8 and MG 63 cells were found to express T beta R-I, T beta R-II, and T beta R-III, and their cell growth was inhibited by TGF-beta, whereas alkaline phosphatase activity was stimulated. Cells that were stably transfected with the T beta RIIDNR plasmid showed decreased response to TGF-beta during growth and alkaline phosphatase activity. These results indicate that the intracellular serine/threonine kinase domain of T beta R-II is essential for signal transduction of the TGF-beta-induced alkaline phosphatase activity as well as growth inhibition.

  20. Glucagon and plasma catecholamines during beta-receptor blockade in exercising man

    DEFF Research Database (Denmark)

    Galbo, H; Holst, Janett; Christensen, N J


    Seven men ran at 60% of individual maximal oxygen uptake to exhaustion during beta-adrenergic blockade with propranolol (P), during lipolytic blockade with nicotinic acid (N), or without drugs (C). The total work times (83 +/- 9 (P), 122 +/- 8 (N), 166 +/- 10 (C) min, mean and SE) differed...... decrease glucagon concentrations increased progressively in parallel with declining plasma glucose and were at exhaustion always three times preexercise values. Thus beta-adrenergic blockade did not diminish the glucagon response. Nor was this response increased when alpha-receptor stimulation in P...... experiments was intensified. Carbohydrate combustion was smaller and NEFA and glycerol concentrations in serum larger during C experiments. Alanine concentrations were never raised at exhaustion. Accordingly, neither stimulation of adrenergic receptors nor NEFA and alanine concentrations are major...

  1. Non-enzymic beta-decarboxylation of aspartic acid. (United States)

    Doctor, V. M.; Oro, J.


    Study of the mechanism of nonenzymic beta-decarboxylation of aspartic acid in the presence of metal ions and pyridoxal. The results suggest that aspartic acid is first converted to oxalacetic acid by transamination with pyridoxal which in turn is converted to pyridoxamine. This is followed by decarboxylation of oxalacetic acid to form pyruvic acid which transaminates with pyridoxamine to form alanine. The possible significance of these results to prebiotic molecular evolution is briefly discussed.

  2. 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: [Department of Histology and Embryology, College of Basic Medical Science, China Medical University, Shenyang 110001 (China); Liu, Rui-tian, E-mail: [Tsinghua University School of Medicine, Haidian District, Beijing 100084 (China)


    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.

  3. N-terminal {beta}{sub 2}-adrenergic receptor polymorphisms do not correlate with bronchodilator response in asthma families

    Energy Technology Data Exchange (ETDEWEB)

    Holyroyd, K.J.; Dragwa, C.; Xu, J. [Johns Hopkins Medical Institutions, Baltimore, MD (United States)] [and others


    Family and twin studies have suggested that susceptibility to asthma is inherited. One clinically relevant phenotype in asthma is the bronchodilator response to beta adrenergic therapy (reversibility) which may also be inherited and vary among asthmatics. Two polymorphisms of the {beta}{sub 2}-adrenergic receptor common to both asthmatic and normal individuals have been reported. One polymorphism, an amino acid polymorphism at position 16, correlated in one study with the need for long-term corticosteriod use in a population of asthmatics. It is conceivable that the increased use of corticosteroids needed to control symptoms in these patients may be explained by a decreased responsiveness to brochodilators mediated through this amino acid polymorphism in the {beta}{sub 2}-adrenergic receptor. However, the response to {beta}{sub 2} bronchodilators was not tested in these patients. In our Dutch asthma families, DNA sequencing of the {beta}{sub 2}-adrenergic receptor has been performed for N-terminal polymorphisms at amino acid positions 16 and 27 in over 100 individuals, and no correlation was found with the increase of FEV{sub 1} in response to bronchodilator. Linkage analysis between bronchodilator response and marker D5S412 near the {beta}{sub 2}-adrenergic receptor gene was performed in 286 sibpairs from these families. Using a bronchodilator response of >10% in FEV{sub 1} as a qualitative definition of affected individuals, there were 145 unaffected sibpairs, 121 sibpairs where one was affected, and 20 in which both were affected. Linear regression analysis of these sibpair data suggested possible linkage (p=0.007). This supports further examination of the {beta}{sub 2}-adrenergic receptor and its regulatory regions for polymorphisms that correlate with the bronchodilator response in asthma families.

  4. 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;


    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...

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

    DEFF Research Database (Denmark)

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


    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...... common esophageal cancer. Alcohol consumption and smoking, which can alter retinoic acid receptor levels, have been identified as key risk factors in the development of carcinoma in the aero-digestive tract. Therefore, the aim of the present study was to evaluate protein levels of retinoic acid receptors...... 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...

  6. Species differences in the localization and number of CNS beta adrenergic receptors: Rat versus guinea pig

    Energy Technology Data Exchange (ETDEWEB)

    Booze, R.M.; Crisostomo, E.A.; Davis, J.N.


    The localization and number of beta adrenergic receptors were directly compared in the brains of rats and guinea pigs. The time course of association and saturability of (125I)cyanopindolol (CYP) binding to slide-mounted tissue sections was similar in rats (Kd = 17 pM) and guinea pigs (Kd = 20 pM). The beta-1 and beta-2 receptor subtypes were examined through the use of highly selective unlabeled receptor antagonists, ICI 118,551 (50 nM) and ICI 89,406 (70 nM). Dramatic species differences between rats and guinea pigs were observed in the neuroanatomical regional localization of the beta adrenergic receptor subtypes. For example, in the thalamus prominent beta-1 and beta-2 receptor populations were identified in the rat; however, the entire thalamus of the guinea pig had few, if any, beta adrenergic receptors of either subtype. Hippocampal area CA1 had high levels of beta-2 adrenergic receptors in both rats and guinea pigs but was accompanied by a widespread distribution of beta-2 adrenergic receptors only in rats. Quantitative autoradiographic analyses of 25 selected neuroanatomical regions (1) confirmed the qualitative differences in CNS beta adrenergic receptor localization, (2) determined that guinea pigs had significantly lower levels of beta adrenergic receptors than rats and (3) indicated a differential pattern of receptor subtypes between the two species. Knowledge of species differences in receptor patterns may be useful in designing effective experiments as well as in exploring the relationships between receptor and innervation patterns. Collectively, these data suggest caution be used in extrapolation of the relationships of neurotransmitters and receptors from studies of a single species.

  7. 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;


    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...... for mutations, but no mutations were detected. Additional screening for mutations of the RII gene revealed a GG to TT base substitution in one cell line, which did not express RII. This mutation generates a stop codon resulting in predicted synthesis of a truncated RII of 219 amino acids. The nature...

  8. 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


    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

  9. Expression of retinoic acid receptors in human endometrial carcinoma. (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


    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.

  10. Expression of TGF-beta1, TGF-beta2, TGF-beta3 and the receptors TGF-betaRI and TGF-betaRII in placentomes of artificially inseminated and nuclear transfer derived bovine pregnancies. (United States)

    Ravelich, S R; Shelling, A N; Wells, D N; Peterson, A J; Lee, R S F; Ramachandran, A; Keelan, J A


    Bovine nuclear transfer pregnancies are characterized by a high incidence of placental abnormalities, notably, increased placentome size and deficiencies in trophoblast cell function and establishment of placental vasculature. Alterations in gene expression during placental growth and development may contribute to the appearance of large placentomes in pregnancies derived from nuclear transfer. The placenta synthesizes a number of cytokines and growth factors, including the transforming growth factor-betas (TGF-betas) that are involved in the establishment, maintenance and/or regulation of pregnancy. All forms of TGF-beta and their receptors are present at the fetal-maternal interface of the bovine placentome, where they are thought to play an important role in regulating growth, differentiation, and function of the placenta. Using real-time RT-PCR, we have examined the expression of TGF-beta1, TGF-beta2, TGF-beta3 and the receptors TGF-betaRI and TGF-betaRII in placentomes of artificially inseminated (AI) and nuclear transfer (NT)-derived bovine pregnancies at days 50, 100 and 150 of gestation. TGF-beta1, TGF-beta2 and TGF-beta3 mRNA expression increased by 2.0-2.8-fold, while TGF-betaRI and TGF-betaRII mRNA expression decreased by 1.7-2.0-fold in NT placentomes compared to AI controls at all gestational ages examined. These findings indicate that NT placentomes may be resistant to the growth suppressive effects of TGF-betas and could contribute to the placental proliferative abnormalities observed in NT-derived placentas. Alternatively, deficiencies in placentation may provide a mechanism whereby TGF-betas are dysregulated in NT pregnancies.

  11. Urease inhibitory activities of beta-boswellic acid derivatives


    Reza Hajiaghaee; Behnam Yousefi; Zinat Bahrampour Omrany; Farzaneh Nabati; Sahand Golestanian; Roya Bazl; Sanaz Golbabaei; "Shamsali Rezazadeh; Massoud Amanlou


    Background and the purpose of the study: Boswellia carterii have been used in traditional medicine for many years for management different gastrointestinal disorders. In this study, we wish to report urease inhibitory activity of four isolated compound of boswellic acid derivative.Methods 4 pentacyclic triterpenoid acids were isolated from Boswellia carterii and identified by NMR and Mass spectroscopic analysis (compounds 1, 3-O-acetyl-9,11-dehydro-beta-boswellic acid; 2, 3-O-acetyl-11-hydrox...

  12. Urease inhibitory activities of beta-boswellic acid derivatives

    Directory of Open Access Journals (Sweden)

    Reza Hajiaghaee


    Full Text Available Background and the purpose of the study: Boswellia carterii have been used in traditional medicine for many years for management different gastrointestinal disorders. In this study, we wish to report urease inhibitory activity of four isolated compound of boswellic acid derivative.Methods 4 pentacyclic triterpenoid acids were isolated from Boswellia carterii and identified by NMR and Mass spectroscopic analysis (compounds 1, 3-O-acetyl-9,11-dehydro-beta-boswellic acid; 2, 3-O-acetyl-11-hydroxy-beta-boswellic acid; 3. 3-O- acetyl-11-keto-beta-boswellic acid and 4, 11-keto-beta-boswellic acid. Their inhibitory activity on Jack bean urease were evaluated. Docking and pharmacophore analysis using AutoDock 4.2 and Ligandscout 3.03 programs were also performed to explain possible mechanism of interaction between isolated compounds and urease enzyme.Results It was found that compound 1 has the strongest inhibitory activity against Jack bean urease (IC50 = 6.27 +/- 0.03 muM, compared with thiourea as a standard inhibitor (IC50 = 21.1 +/- 0.3 muM.Conclusion The inhibition potency is probably due to the formation of appropriate hydrogen bonds and hydrophobic interactions between the investigated compounds and urease enzyme active site and confirms its traditional usage.

  13. Shared receptor components but distinct complexes for alpha and beta interferons. (United States)

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


    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.

  14. Subtype selective kainic acid receptor agonists

    DEFF Research Database (Denmark)

    Bunch, Lennart; Krogsgaard-Larsen, Povl


    (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 (m......GluRs). Within the iGluRs, five subtypes (KA1, KA2, iGluR5-7) show high affinity and express full agonist activity upon binding of the naturally occurring amino acid kainic acid (KA). Thus these receptors have been named the KA receptors. This review describes all-to our knowledge-published KA receptor agonists...

  15. Endoglin structure and function - Determinants of endoglin phosphorylation by transforming growth factor-beta receptors

    NARCIS (Netherlands)

    Koleva, Rositsa I.; Conley, Barbara A.; Romero, Diana; Riley, Kristin S.; Marto, Jarrod A.; Lux, Andreas; Vary, Calvin P. H.


    Determination of the functional relationship between the transforming growth factor-beta(TGF beta) receptor proteins endoglin and ALK1 is essential to the understanding of the human vascular disease, hereditary hemorrhagic telangiectasia. TGF beta 1 caused recruitment of ALK1 into a complex with end

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

    Directory of Open Access Journals (Sweden)

    Robichon Alain


    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.

  17. HPLC Analysis of [Alpha]- and [Beta]-Acids in Hops (United States)

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


    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…

  18. Regulation by retinoids of luteinizing hormone/chorionic gonadotropin receptor, cholesterol side-chain cleavage cytochrome P-450, 3 beta-hydroxysteroid dehydrogenase/delta (5-4)-isomerase and 17 alpha-hydroxylase/C17-20 lyase cytochrome P-450 messenger ribonucleic acid levels in the K9 mouse Leydig cell line. (United States)

    Lefèvre, A; Rogier, E; Astraudo, C; Duquenne, C; Finaz, C


    Vitamin A is a potent regulator of testicular function. We have reported that retinol (R) and retinoic acid (RA) induced a down regulation of luteinizing hormone/human chorionic gonadotropin (LH/CG) binding sites in K9 Leydig cells. In the present study we evaluated the effect of R and RA on LH/CG receptors, cholesterol side-chain cleavage cytochrome P-450 (P-450 scc), 17 alpha-hydroxylase/C17-20 lyase (P-450 17 alpha) and 3 beta-hydroxysteroid dehydrogenase (3 beta HSD) mRNA levels in K9 mouse Leydig cells. To validate K9 cells as a model for studying Leydig cell steroidogenesis at the molecular level, we first investigated the effect of hCG on mRNA levels of the steroidogenic enzymes. P-450 scc, 3 beta HSD and P-450 17 alpha were expressed constitutively. The addition of 10 ng/ml hCG enhanced mRNA levels for the three genes within 2 h. Maximal accumulation of P-450 scc, P-450 17 alpha and 3 beta HSD mRNA in treated cells represents a 2.5-, 8.5- and 4-fold increase over control values, respectively. P-450 17 alpha expression reached a maximum by 4 h and then declined rapidly to return to control value by 24 h. The pattern of LH/CG receptor mRNAs in K9 cells was very similar to that of MA10 Leydig cells and showed six transcripts of 1.1, 1.6, 1.9, 2.6, 4.2 and 7.0 kb. Treatment of cells with R or RA resulted in a time- and dose-dependent decrease in all six species.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. Beta-adrenergic receptors are differentially expressed in distinct interneuron subtypes in the rat hippocampus. (United States)

    Cox, David J; Racca, Claudia; LeBeau, Fiona E N


    Noradrenaline (NA) acting via beta-adrenergic receptors (betaARs) plays an important role in the modulation of memory in the hippocampus. betaARs have been shown to be expressed in principal cells, but their distribution across different interneuron classes is unknown. We have used specific interneuron markers including calcium binding proteins (parvalbumin, calbindin, and calretinin) and neuropeptides (somatostatin, neuropeptide Y, and cholecystokinin) together with either beta1AR or beta2AR to determine the distribution of these receptors in all major subfields of the hippocampus. We found that beta1AR-expressing interneurons were more prevalent in the CA3 and CA1 regions of the hippocampus than in the dentate gyrus, where they were relatively sparse. beta2AR-expressing interneurons were more uniformly distributed between all three regions of the hippocampus. A high proportion of neuropeptide Y-containing interneurons in the dentate gyrus co-expressed beta2AR. beta1AR labeling was common in interneurons expressing somatostatin and parvalbumin in the CA3 and CA1 regions, particularly in the stratum oriens of these regions. beta2AR labeling was more likely to be found than beta1AR labeling in cholecystokinin-expressing interneurons. In contrast, calretinin-containing interneurons were virtually devoid of beta1AR or beta2AR labeling. These regional and interneuron type-specific differences suggest functionally distinct roles for NA in modulating hippocampal activity via activation of betaARs.


    NARCIS (Netherlands)



    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

  1. Random length assortment of human and mouse T cell receptor for antigen alpha and beta chain CDR3. (United States)

    Johnson, G; Wu, T T


    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.

  2. 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


    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...

  3. Pregnancy modifies the alpha2-beta-adrenergic receptor functional balance in rabbit fat cells. (United States)

    Bousquet-Mélou, A; Muñoz, C; Galitzky, J; Berlan, M; Lafontan, M


    The sympathetic nervous system controls lipolysis in fat by activation of four adrenergic receptors: beta1, beta2, beta3, and alpha2. During pregnancy, maternal metabolism presents anabolic and catabolic phases, characterized by modifications of fat responsiveness to catecholamines. The contributions of the four adrenergic receptors to adipocyte responsiveness during pregnancy have never been studied. Our aim was to evaluate the influence of pregnancy on adrenergic receptor-mediated lipolysis in rabbit white adipocytes. Functional studies were performed using subtype-selective and non-selective adrenergic receptor agonists. Overall adrenergic responsiveness was measured with the physiological agonist epinephrine. Non-adrenergic agents were used to evaluate different steps of the lipolytic cascade. The alpha2- and beta1/beta2-adrenergic receptor numbers were determined with selective radioligands. Non-adrenergic agents revealed that pregnancy induced an intracytoplasmic modification of the lipolytic cascade in inguinal but not in retroperitoneal adipocytes. Pregnancy induced an increase in beta1- and specially beta3-mediated lipolysis. The amounts of adipocyte beta1/beta2- and alpha2-adrenergic receptors were increased in pregnant rabbits. Epinephrine effects revealed an increased contribution of alpha2-adrenergic receptor-mediated antilipolysis in adipocytes from pregnant rabbits. These results indicate that pregnancy regulates adipocyte responsiveness to catecholamines mainly via the alpha2- and beta3-adrenergic pathways. Pregnancy induces an intracytoplasmic modification of the lipolytic cascade, probably via hormone-sensitive lipase, with differences according to fat location.-Bousquet-Mélou, A., C. Muñoz, J. Galitzky, M. Berlan, and M. Lafontan. Pregnancy modifies the alpha2-beta-adrenergic receptor functional balance in rabbit fat cells.

  4. Modulation of estrogen receptor-beta isoforms by phytoestrogens in breast cancer cells. (United States)

    Cappelletti, Vera; Miodini, Patrizia; Di Fronzo, Giovanni; Daidone, Maria Grazia


    High consumption of phytoestrogen-rich food correlates with reduced incidence of breast cancer. However, the effect of phytoestrogens on growth of pre-existing breast tumors presents concerns when planning the use of phytoestrogens as chemoprevention st rategy. Genistein, the active phytoestrogen in soy, displays weak estrogenic activity mediated by estrogen receptor (ER) with a preferential binding for the ER-beta species. However, no information is at present available on the interaction between phytoestrogens and the various isoforms generated by alternative splicing. In two human breast cancer cell lines, T47D and BT20, which express variable levels of ER-beta, the effect of genistein and quercetin was evaluated singly and in comparison with 17beta-estradiol, on mRNA expression of estrogen receptor-beta (ER-beta) isoforms evaluated by a triple primer RT-PCR assay. In T47D cells estradiol caused a 6-fold up-regulation of total ER-beta, and modified the relative expression pattern of the various isoforms, up-regulating the beta2 and down-regulating the beta5 isoform. Genistein up-regulated ER-beta2 and ER-beta1 in T47D cells, and after treatment the ER-beta2 isoform became prevalent, while in BT20 cells it almost doubled the percent contribution of ER-beta1 and ER-beta2 to total ER-beta. Quercetin did not alter the total levels nor the percent distribution of ER-beta isoforms in either cell line. Genistein, through the modulation of ER-beta isoform RNA expression inhibited estrogen-promoted cell growth, without interfering on estrogen-regulated transcription. ER-beta and its ER-beta mRNA isoforms may be involved in a self-limiting mechanism of estrogenic stimulation promoted either by the natural hormone or by weaker estrogen agonists like genistein.

  5. Synthetic resveratrol aliphatic acid inhibits TLR2-mediated apoptosis and an involvement of Akt/GSK3beta pathway. (United States)

    Chen, Lin; Zhang, Yi; Sun, Xiuli; Li, Hui; LeSage, Gene; Javer, Avani; Zhang, Xiumei; Wei, Xinbing; Jiang, Yulin; Yin, Deling


    As resveratrol derivatives, resveratrol aliphatic acids were synthesized in our laboratory. Previously, we reported the improved pharmaceutical properties of the compounds compared to resveratrol, including better solubility in water and much tighter binding with human serum albumin. Here, we investigate the role of resveratrol aliphatic acids in Toll-like receptor 2 (TLR2)-mediated apoptosis. We showed that resveratrol aliphatic acid (R6A) significantly inhibits the expression of TLR2. In addition, overexpression of TLR2 in HEK293 cells caused a significant decrease in apoptosis after R6A treatment. Moreover, inhibition of TLR2 by R6A decreases serum deprivation-reduced the levels of phosphorylated Akt and phosphorylated glycogen synthase kinase 3beta (GSK3beta). Our study thus demonstrates that the resveratrol aliphatic acid inhibits cell apoptosis through TLR2 by the involvement of Akt/GSK3beta pathway.

  6. TGF-beta isoforms and TGF-beta receptors in drug-induced and hereditary gingival overgrowth. (United States)

    Wright, H J; Chapple, I L; Matthews, J B


    Drug therapy and hereditary factors are two of the main causes of gingival overgrowth (GO). Both of these forms of GO are associated with increased extracellular matrix production by fibroblasts. Transforming growth factor beta (TGF-beta) is an important mediator of wound healing and tissue regeneration, which stimulates fibroblasts to produce extracellular matrix materials. The aim of this immunohistochemical study was to determine whether there is any altered expression of TGF-beta isoforms or its receptors in tissue from patients with drug-induced GO (DIGO; n=10) and hereditary gingival fibromatosis (n=10) when compared to non-overgrowth tissue (n=10). Compared to control tissues, significantly more fibroblasts expressed TGF-beta1 in both DIGO and hereditary gingival fibromatosis tissues (Pfibroblast densities between groups, there was a proportional increase in TGF-beta3 as well as TGF-beta1 expressing cells within both overgrowth populations (Preceptor-positive cells in the total cell population analysed in overgrowth tissues (Pisoform and receptor expression by fibroblasts in gingival overgrowth that may contribute to disease pathogenesis.

  7. Association of coatomer proteins with the beta-receptor for platelet-derived growth factor

    DEFF Research Database (Denmark)

    Hansen, Klaus; Rönnstrand, L; Rorsman, C


    of intracellular vesicle transport. In order to explore the functional significance of the interaction between alpha- and beta'-COP and the PDGF receptor, a receptor mutant was made in which the conserved histidine residue 928 was mutated to an alanine residue. The mutant receptor, which was unable to bind alpha......The nonreceptor tyrosine kinase Src binds to and is activated by the beta-receptor for platelet-derived growth factor (PDGF). The interaction leads to Src phosphorylation of Tyr934 in the kinase domain of the receptor. In the course of the functional characterization of this phosphorylation, we...... noticed that components of 136 and 97 kDa bound to a peptide from this region of the receptor in a phosphorylation-independent manner. These components have now been purified and identified as alpha- and beta'-coatomer proteins (COPs), respectively. COPs are a family of proteins involved in the regulation...

  8. 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: [Center for Healthcare Technology Development, Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Jeonju, Jeonbuk 561-756 (Korea, Republic of)


    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

  9. 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


    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...

  10. The benzodiazepine receptor in rat brain and its interaction with ethyl beta-carboline-3-carboxylate

    Energy Technology Data Exchange (ETDEWEB)

    Martin, I.L.; Doble, A.


    (3H)Ethyl beta-carboline-3-carboxylate ((3H) beta-CCE) binds to a homogeneous population of recognition sites in rat whole brain membranes with high affinity. The (3H)beta-CCE binding is completely displaceable by low concentrations of a number of benzodiazepines with similar potencies found when using a 3H-benzodiazepine as the ligand. This suggests that the recognition sites for beta-CCE and the benzodiazepines are identical or that they are involved in a close interaction. The binding of (3H)beta-CCE does not obey simple mass-action kinetics. (3H)Flunitrazepam dissociation from its receptor population is biphasic, and different methods of initiation of this dissociation indicate that cooperative interactions take place within the receptor population. We conclude that the benzodiazepine receptor is a single entity that can exist in two conformations, the equilibrium between which may be controlled by some as yet unidentified factor.

  11. Leptin upregulates beta3-integrin expression and interleukin-1beta, upregulates leptin and leptin receptor expression in human endometrial epithelial cell cultures. (United States)

    Gonzalez, R R; Leavis, P


    Human endometrium and endometrial epithelial cells (EECs) either cultured alone or cocultured with human embryos express leptin and leptin receptor. This study compares the effect of leptin with that of interleukin-1beta (IL-1beta) on the expression of beta3-EEC integrin, a marker of endometrial receptivity. Both cytokines increased the expression of beta3-EEC at concentrations in the range of 0.06-3 nM; however, leptin exhibited a significantly greater effect than IL-1beta. We also determined the regulatory effects of IL-1beta on leptin secretion and on the expression of leptin and leptin receptor at the protein level in both EEC and endometrial stromal cell (ESC) cultures. In EEC cultures, IL-1beta upregulated secretion of leptin and expression of both leptin and leptin receptors. No effect of IL-1beta was found in the ESC cultures. However, leptin exhibited marginal upregulation of leptin receptor. The upregulation of beta3-integrin and leptin/leptin receptor expression by IL-1beta in EEC cultures indicates that both cytokines may be implicated in embryonic-maternal cross-talk during the early phase of human implantation. Our present data also raise the possibility that leptin is an endometrial molecular effector of IL-1beta action on beta3-integrin upregulation. Thus, a new role for leptin in human reproduction as an autocrine/paracrine regulator of endometrial receptivity is proposed.

  12. Azetidine-2-carboxylic acid in garden beets (Beta vulgaris). (United States)

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


    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).

  13. Anxiolytics not acting at the benzodiazepine receptor: beta blockers. (United States)

    Tyrer, P


    1. Although there is clear evidence for many controlled trials in the past 25 years that beta blockers are effective in anxiety disorders clear indications for their use are lacking. 2. The balance of evidence suggests that the mechanism of action of beta-blocking drugs is through peripheral blockade of beta-mediated symptoms. 3. Most evidence to the efficacy of beta-blockers comes from study of their use in generalized anxiety and in acute stress. 4. Because beta-blockers carry no risks of pharmacological dependence they may be preferred to many other anti-anxiety drugs.

  14. The transforming growth factor-beta receptor genes and the risk of intracranial aneurysms

    NARCIS (Netherlands)

    Ruigrok, Ynte M.; Baas, Annette F.; Medic, Jelena; Wijmenga, Cisca; Rinkel, Gabriel J. E.


    Background Mutations in the receptor genes of the transforming growth factor beta pathway, TGFBR1 and TGFBR2, cause syndromes with thoracic aortic aneurysms, while genetic variants in TGFBR1 and TGFBR2 are associated with abdominal aortic aneurysms. The transforming growth factor-beta pathway may be

  15. 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;


    Structural analysis of G-protein-coupled receptors (GPCRs) for hormones and neurotransmitters has been hindered by their low natural abundance, inherent structural flexibility, and instability in detergent solutions. Here we report a structure of the human beta2 adrenoceptor (beta2AR), which...

  16. Abscisic Acid Receptors: Past, Present and Future

    Institute of Scientific and Technical Information of China (English)

    Jianjun Guo; Xiaohan Yang; David J. Weston; Jin-Gui Chen


    Abscisic acid (ABA) is the key plant stress hormone. Consistent with the earlier studies in support of the presence of both membrane- and cytoplasm-localized ABA receptors, recent studies have identified multiple ABA receptors located in various subcellular locations. These include a chloroplast envelope-localized receptor (the H subunit of Chloroplast Mg2+-chelatase/ABA Receptor), two plasma membrane-localized receptors (G-protein Coupled Receptor 2 and GPCR-type G proteins),and one cytosol/nucleus-localized Pyrabactin Resistant (PYR)/PYR-Like (PYL)/Regulatory Component of ABA Receptor 1 (RCAR). Although the downstream molecular events for most of the identified ABA receptors are currently unknown, one of them, PYR/PYL/RCAR was found to directly bind and regulate the activity of a long-known central regulator of ABA signaling, the A-group protein phosphatase 2C (PP2C). Together with the Sucrose Non-fermentation Kinase Subfamily 2 (SnRK2s) protein kinases, a central signaling complex (ABA-PYR-PP2Cs-SnRK2s) that is responsible for ABA signal perception and transduction is supported by abundant genetic, physiological, biochemical and structural evidence. The identification of multiple ABA receptors has advanced our understanding of ABA signal perception and transduction while adding an extra layer of complexity.

  17. Complex Pharmacology of Free Fatty Acid Receptors

    DEFF Research Database (Denmark)

    Milligan, Graeme; Shimpukade, Bharat; Ulven, Trond


    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....

  18. Alterations in the oxygen deficit-oxygen debt relationships with beta-adrenergic receptor blockade in man. (United States)

    Hughson, R L


    The effects of beta-adrenergic receptor blockade (100 mg oral metoprolol) or matched placebo on gas exchange kinetics were studied in six males. Ventilation and gas exchange were monitored in four transitions for each treatment from loadless pedalling (0 W) to a selected work rate (100 W) and back to 0 W. Breath-by-breath data were averaged for analysis. Oxygen uptake (VO2) kinetics were significantly slowed at the onset of exercise and recovery by beta-blockade. This resulted in larger oxygen deficit and oxygen debt (671 +/- 115, 586 +/- 87 ml O2, respectively) for beta-blockade than for placebo (497 +/- 87, 474 +/- 104 ml O2). In addition, oxygen deficit was significantly larger than oxygen debt during beta-blockade tests. These results can be explained by greater utilization of oxygen and creatine phosphate stores as well as anaerobic glycolysis at the onset of 100 W exercise with beta-blockade. Carbon dioxide output (VCO2) kinetics were significantly slowed by beta-blockade only at the onset of exercise. Expired ventilation (VE) kinetics were not affected by beta-blockade. At 0 W, VE was significantly reduced by beta-blockade. Heart rate was lower at all times with beta-blockade. Kinetics of heart rate were not affected. These data for VO2 kinetics at the start and end of exercise indicate that even in moderate-intensity exercise, lactic acid production can contribute significantly to energy supply. The use of the term ' alactic ' to describe the deficit and debt associated with this exercise is not appropriate.

  19. Characterization and regulation of. beta. /sub 2/-adrenergic receptors in rat vas deferens

    Energy Technology Data Exchange (ETDEWEB)

    May, J.M.


    ..beta../sub 2/-Adrenergic receptors in rat vas deferens were examined by measuring the binding of /sup 125/I-pindolol (/sup 125/IPIN) to membrane preparations and the inhibition of evoked contractions in intact tissues. /sup 125/IPIN labeled a single class of binding sites with mass action kinetics. Affinity constants for ..beta..-adrenergic receptor antagonists calculated from both binding and functional experiments agreed well, suggesting that /sup 125/IPIN labels the functional ..beta../sub 2/-adrenergic receptor. n-Bromoacetylalprenololmenthane (BAAM) was used to decrease receptor density so that agonist affinity constants could be determined functionally. Treatment of tissues with BAAM decreased the functional potencies of agonists. Higher concentrations of BAAM decreased the maximum tissue response. Affinity constants for agonists calculated after BAAM treatment were compared to affinity constants determined from binding studies done under conditions designed to promote high or low affinity agonist binding. Functional affinity constants for isoproterenol and salbutamol agreed with the low affinity binding constants, suggesting that the low affinity form of the receptor initiates the functional response. Because acute denervation of vasa deferentia did not alter the density of /sup 125/IPIN binding sites, the sites are probably post-junctional. Chronic infusion of isoproterenol reduced the potency of isoproterenol, the maximum tissue response, and the receptor density. These results suggest that ..beta..-adrenergic receptor density and responsiveness in rat vas deferens are not affected by removing catecholamine sources, but receptor density and responsiveness can be decreased by increasing agonist concentration at the receptor.

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


    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

  1. Candidate gene study of TRAIL and TRAIL receptors: association with response to interferon beta therapy in multiple sclerosis patients.

    Directory of Open Access Journals (Sweden)

    Carlos López-Gómez

    Full Text Available 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.

  2. 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


    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

  3. 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: [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)


    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.

  4. Platelets possess functional TGF-beta receptors and Smad2 protein. (United States)

    Lev, P R; Salim, J P; Marta, R F; Osorio, M J Mela; Goette, N P; Molinas, F C


    TGF-beta1 plays a main role in tissue repair by regulating extracellular matrix production and tissue granulation. Platelets are one of the main sources of this cytokine in the circulation. The aim of this study was to evaluate the presence of the TGF-beta receptors on platelets, the effect of TGF-beta1 on platelet aggregation and the underlying intracellular mechanisms. TGF-beta receptors on platelets were studied by flow cytometry and their mRNA by PCR. Platelet aggregation was assessed by turbidimetric methods and intracellular pathways by Western blot. TGF-beta receptor type II and mRNA codifying for TbetaRI and TbetaRII were found in platelets. We demonstrated that TGF-beta1 did not trigger platelet aggregation by itself but had a modulating effect on ADP-induced platelet aggregation. Either inhibition or increase in platelet aggregation, depending on the exposure time to TGF-beta1 and the ADP concentration used, were shown. We found that platelets possess Smad2 protein and that its phosphorylation state is increased after exposure to TGF-beta1. Besides, TGF-beta1 modified the pattern of ADP-induced tyrosine phosphorylation. Increased phosphorylation levels of 64-, 80- and 125-kDa proteins during short time incubation with TGF-beta1 and increased phosphorylation of 64- and 125-kDa proteins after longer incubation were observed. The modulating effect of TGF-beta1 on platelet aggregation could play a role during pathological states in which circulating TGF-beta1 levels are increased and intravascular platelet activation is present, such as myeloproliferative disorders. In vascular injury, in which platelet activation followed by granule release generates high local ADP concentrations, it could function as a physiological mechanism of platelet activation control.

  5. 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;


    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 propagates...... signals to Smad proteins, which mediate the activation of TGF-beta target genes. In this study, we identify ADAM12 (a disintegrin and metalloproteinase 12) as a component of the TGF-beta signaling pathway that acts through association with TbetaRII. We found that ADAM12 functions by a mechanism...... independent of its protease activity to facilitate the activation of TGF-beta signaling, including the phosphorylation of Smad2, association of Smad2 with Smad4, and transcriptional activation. Furthermore, ADAM12 induces the accumulation of TbetaRII in early endosomal vesicles and stabilizes the Tbeta...

  6. Differential modulation of Beta-adrenergic receptor signaling by trace amine-associated receptor 1 agonists.

    Directory of Open Access Journals (Sweden)

    Gunnar Kleinau

    Full Text Available Trace amine-associated receptors (TAAR are rhodopsin-like G-protein-coupled receptors (GPCR. TAAR are involved in modulation of neuronal, cardiac and vascular functions and they are potentially linked with neurological disorders like schizophrenia and Parkinson's disease. Subtype TAAR1, the best characterized TAAR so far, is promiscuous for a wide set of ligands and is activated by trace amines tyramine (TYR, phenylethylamine (PEA, octopamine (OA, but also by thyronamines, dopamine, and psycho-active drugs. Unfortunately, effects of trace amines on signaling of the two homologous β-adrenergic receptors 1 (ADRB1 and 2 (ADRB2 have not been clarified yet in detail. We, therefore, tested TAAR1 agonists TYR, PEA and OA regarding their effects on ADRB1/2 signaling by co-stimulation studies. Surprisingly, trace amines TYR and PEA are partial allosteric antagonists at ADRB1/2, whereas OA is a partial orthosteric ADRB2-antagonist and ADRB1-agonist. To specify molecular reasons for TAAR1 ligand promiscuity and for observed differences in signaling effects on particular aminergic receptors we compared TAAR, tyramine (TAR octopamine (OAR, ADRB1/2 and dopamine receptors at the structural level. We found especially for TAAR1 that the remarkable ligand promiscuity is likely based on high amino acid similarity in the ligand-binding region compared with further aminergic receptors. On the other hand few TAAR specific properties in the ligand-binding site might determine differences in ligand-induced effects compared to ADRB1/2. Taken together, this study points to molecular details of TAAR1-ligand promiscuity and identified specific trace amines as allosteric or orthosteric ligands of particular β-adrenergic receptor subtypes.

  7. Enhanced expression of the type II transforming growth factor beta receptor in human pancreatic cancer cells without alteration of type III receptor expression. (United States)

    Friess, H; Yamanaka, Y; Büchler, M; Berger, H G; Kobrin, M S; Baldwin, R L; Korc, M


    We have recently found that human pancreatic adenocarcinomas exhibit strong immunostaining for the three mammalian transforming growth factor beta (TGF-beta) isoforms. These important growth-regulating polypeptides bind to a number of proteins, including the type I TGF-beta receptor (T beta R-I), type II TGF-beta receptor (T beta R-II), and the type III TGF-beta receptor (T beta R-III). In the present study we sought to determine whether T beta R-II and T beta R-III expression is altered in pancreatic cancer. Northern blot analysis indicated that, by comparison with the normal pancreas, pancreatic adenocarcinomas exhibited a 4.6-fold increase (P beta R-II. In contrast, mRNA levels encoding T beta R-III were not increased. In situ hybridization showed that T beta R-II mRNA was expressed in the majority of cancer cells, whereas mRNA grains encoding T beta R-III were detectable in only a few cancer cells and were present mainly in the surrounding stroma. These findings suggest that enhanced levels of T beta R-II may have a role in regulating human pancreatic cancer cell growth, while T beta R-III may function in the extracellular matrix.

  8. Induction of interleukin 2 receptor beta chain expression by self-recognition in the thymus. (United States)

    Hanke, T; Mitnacht, R; Boyd, R; Hünig, T


    1-2% of adult mouse thymocytes express the T cell receptor alpha/beta (TCR-alpha/beta) together with the interleukin (IL) 2R beta (p70), but not the alpha (p 55) chain. We show that the previously described alpha/beta-TCR +CD4-8- and the partially overlapping Ly6C+ thymocytes are contained within this subset. Most IL-2R beta+ alpha/beta-TCR+ cells have a mature and activated (heat stable antigen [HSA]-, thymic shared antigen 1 [TSA-1]-, CD44high, CD69+) phenotype. Overrepresentation of V beta 8.2 in both CD4-8- and CD4 and/or CD8+ IL-2R beta+ thymocytes suggests that IL-2R beta expression is induced by a TCR-mediated activation event. In mice transgenic for an H-2Kb-specific TCR, IL-2R beta+ cells were abundant under conditions of mainstream negative selection, i.e., in the presence of Kb, but absent under conditions of mainstream positive selection or in a nonselecting environment. Together, these results show that in addition to clonal deletion, self-recognition by immature thymocytes leads to phenotypic maturation of a small subset of thymocytes expressing IL-2R beta. IL-2-deficient mice contain normal numbers of IL-2R beta+ alpha/beta-TCR+ thymocytes, indicating that like mainstream T cell development, this minor pathway of positive selection does not depend on IL-2. However, in the absence of IL-2, the CD4/CD8 subset composition of IL-2R beta+ thymocytes is skewed towards CD4-8+, mostly at the expense of CD4-8-. A possible relevance of this finding for the development of the immune pathology of IL-2-deficient mice is discussed.

  9. Cyanide-insensitive and clofibrate enhanced beta-oxidation of dodecanedioic acid in rat liver. An indication of peroxisomal beta-oxidation of N-dicarboxylic acids. (United States)

    Mortensen, P B; Kølvraa, S; Gregersen, N; Rasmussen, K


    The beta-oxidation rate of dodecanedioic acid in rat liver homogenates (600 X g supernatant fraction) was determined by simultaneous measurements of the C6-C12-dicarboxylic acids, i.e., adipic, suberic, sebacic and dodecanedioic acids, in relation to time in assays incubated with dodecanedioic acid. Measurements were performed by a combined gas chromatographic-mass spectrometric technique, i.e., selected ion-monitoring. The beta-oxidation rate was registered as the consumption rate of dodecanedioic acid and as the initial rise in the concentrations of C6-C10-dicarboxylic acids. The beta-oxidation rate of C8-C12-dicarboxylic acids was increased many times in homogenates from clofibrate-treated rats. Moreover, it was unexpectedly found that 2.0 mM cyanide was unable to inhibit the beta-oxidation rate of the dicarboxylic acids in vitro, but in fact caused a minor increase in the rate of beta-oxidation in homogenates from both normal and clofibrate-treated rats. It was concluded that the present results strongly indicate the existence of a peroxisomal beta-oxidation of dicarboxylic acids.

  10. Immunoanalogue of vertebrate beta-adrenergic receptor in the unicellular eukaryote Paramecium. (United States)

    Wiejak, Jolanta; Surmacz, Liliana; Wyroba, Elzbieta


    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.

  11. Induction of the expression of genes encoding TGF-beta isoforms and their receptors by inositol hexaphosphate in human colon cancer cells. (United States)

    Kapral, Małgorzata; Wawszczyk, Joanna; Hollek, Andrzej; Weglarz, Ludmiła


    Transforming growth factors-beta (TGF-beta) are multifunctional cytokines involved in the regulation of cell development, differentiation, survival and apoptosis. They are also potent anticancer agents that inhibit uncontrolled proliferation of cells. Incorrect TGF-beta regulation has been implicated in the pathogenesis of many diseases including inflammation and cancer. In humans, the TGF-beta family consists of three members (TGF-beta1, 2, 3) that show high similarity and homology. TGF-betas exert biological activities on various cell types including neoplastic cells via their specific receptors. Inositol hexaphosphate (phytic acid, IP6), a phytochemical has been reported to possess various health benefits. The aim of this study was to examine the effect of IP6 on the expression of genes encoding TGF-beta1, TGF-beta2, TGF-beta3 isoforms and their receptors TbetaRI, TbetaRII, TbetaRIII in human colorectal cancer cell line Caco-2. The cells were treated with 0.5, 1 and 2.5 mM IP6 for 3, 6 and 12 h. The untreated Caco-2 cells were used as the control. Quantification of genes expression was performed by real time QRT-PCR technique with a SYBR Green I chemistry. The experimental data revealed that the TGF-beta1 mRNA was the predominant isoform in Caco-2 cells and that IP6 enhanced transcriptional activity of genes of all three TGF-beta isoforms and their receptors TbetaRI, TbetaRII TbetaRIII in these cells. At concentrations up to 1 mM, IP6 over-expressed the genes in 6 h lasting cultures, and its higher dose (2.5 mM) caused successively increasing transcript level of TGF-beta isoforms and receptors with the duration of experiment up to 12 h. The findings of this study indicate that one of anti-cancer abilities of IP6 can be realized by enhancing the gene expression of TGF-beta isoforms and their receptors at the transcriptional level.

  12. Receptor density is key to the alpha2/beta interferon differential activities. (United States)

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


    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.

  13. Activity of cytisine and its brominated isosteres on recombinant human alpha7, alpha4beta2 and alpha4beta4 nicotinic acetylcholine receptors. (United States)

    Houlihan, L M; Slater, Y; Guerra, D L; Peng, J H; Kuo, Y P; Lukas, R J; Cassels, B K; Bermudez, I


    Effects of cytisine (cy), 3-bromocytisine (3-Br-cy), 5-bromocytisine (5-Br-cy) and 3,5-dibromocytisine (3,5-diBr-cy) on human (h) alpha7-, alpha4beta2- and alpha4beta4 nicotinic acetylcholine (nACh) receptors, expressed in Xenopus oocytes and cell lines, have been investigated. Cy and its bromo-isosteres fully inhibited binding of both [alpha-(125)I]bungarotoxin ([alpha-(125)I]BgTx) to halpha7- and [(3)H]cy to halpha4beta2- or halpha4beta4-nACh receptors. 3-Br-cy was the most potent inhibitor of both [alpha-(125)I]BgTx and [(3)H]cy binding. Cy was less potent than 3-Br-cy, but 5-Br-cy and 3,5-diBr-cy were the least potent inhibitors. Cy and 3-Br-cy were potent full agonists at halpha7-nACh receptors but behaved as partial agonists at halpha4beta2- and halpha4beta4-nACh receptors. 5-Br-cy and 3,5-diBr-cy had low potency and were partial agonists at halpha7- and halpha4beta4-nACh receptors, but they elicited no responses on halpha4beta2-nACh receptors. Cy and 3-Br-cy produced dual dose-response curves (DRC) at both halpha4beta2- and halpha4beta4-nACh receptors, but ACh produced dual DRC only at halpha4beta2-nACh receptors. Low concentrations of cy, 3-Br-cy and 5-Br-cy enhanced ACh responses of oocytes expressing halpha4beta2-nACh receptors, but at high concentrations they inhibited the responses. In contrast, 3,5-diBr-cy only inhibited, in a competitive manner, ACh responses of halpha4beta2-nACh receptors. It is concluded that bromination of the pyridone ring of cy produces marked changes in effects of cy that are manifest as nACh receptor subtype-specific differences in binding affinities and in functional potencies and efficacies.

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

    DEFF Research Database (Denmark)

    Jessen, H; Røigaard, H; Jacobsen, Christian


    The transport characteristics of amino acids in primary cell cultures from the proximal tubule of human adults (AHKE cells) were examined, using alpha-aminoisobutyric acid (AIB) and beta-alanine as representatives of alpha- and beta-amino acids, respectively. The Na(+)-gradient dependent influx...... of AIB occurred by a single, saturable transport system, whereas the Na(+)-gradient dependent uptake data for beta-alanine could be described in terms of two-independent transport components as well as one-transport one-leak model with identical kinetic constants for the high-affinity system. Competition...... experiments revealed that all the neutral amino acids tested reduced the uptake of AIB, whereas there was no effect of taurine, L-aspartic acid, and L-arginine. By contrast, the influx of beta-alanine was only drastically reduced by beta-amino acids, whereas the inhibition by neutral alpha-amino acids...

  15. The nicotinic receptor in the rat pineal gland is an alpha3beta4 subtype. (United States)

    Hernandez, Susan C; Vicini, Stefano; Xiao, Yingxian; Dávila-García, Martha I; Yasuda, Robert P; Wolfe, Barry B; Kellar, Kenneth J


    The rat pineal gland contains a high density of neuronal nicotinic acetylcholine receptors (nAChRs). We characterized the pharmacology of the binding sites and function of these receptors, measured the nAChR subunit mRNA, and used subunit-specific antibodies to establish the receptor subtype as defined by subunit composition. In ligand binding studies, [3H]epibatidine ([3H]EB) binds with an affinity of approximately 100 pM to nAChRs in the pineal gland, and the density of these sites is approximately 5 times that in rat cerebral cortex. The affinities of nicotinic drugs for binding sites in the pineal gland are similar to those at alpha3beta4 nAChRs heterologously expressed in human embryonic kidney 293 cells. In functional studies, the potencies and efficacies of nicotinic drugs to activate or block whole-cell currents in dissociated pinealocytes match closely their potencies and efficacies to activate or block 86Rb+ efflux in the cells expressing heterologous alpha3beta4 nAChRs. Measurements of mRNA indicated the presence of transcripts for alpha3, beta2, and beta4 nAChR subunits but not those for alpha2, alpha4, alpha5, alpha6, alpha7, or beta3 subunits. Immunoprecipitation with subunit-specific antibodies showed that virtually all [3H]EB-labeled nAChRs contained alpha3 and beta4 subunits associated in one complex. The beta2 subunit was not associated with this complex. Taken together, these results indicate that virtually all of the nAChRs in the rat pineal gland are the alpha3beta4 nAChR subtype and that the pineal gland can therefore serve as an excellent and convenient model in which to study the pharmacology and function of these receptors in a native tissue.

  16. A molecular dynamics approach to receptor mapping: application to the 5HT3 and beta 2-adrenergic receptors. (United States)

    Gouldson, P R; Winn, P J; Reynolds, C A


    A molecular dynamics-based approach to receptor mapping is proposed, based on the method of Rizzi (Rizzi, J. P.; et al. J. Med. Chem. 1990, 33, 2721). In Rizzi's method, the interaction energy between a series of drug molecules and probe atoms (which mimic functional groups on the receptor, such as hydrogen bond donors) was calculated. These interactions were calculated on a three-dimensional grid within a molecular mechanics parameters, were placed at these minima. The distances between the dummy atom sites were monitored during molecular dynamics simulations and plotted as distance distribution functions. Important distances within the receptor became apparent, as drugs with a common mode of binding share similar peaks in the distance distribution functions. In the case of specific 5HT3 ligands, the important donor--acceptor distance within the receptor has a range of ca. 7.9--8.9 A. In the case of specific beta 2-adrenergic ligands, the important donor--acceptor distances within the receptor lie between ca. 7--9 A and between 8 and 10 A. These distances distribution functions were used to assess three different models of the beta 2-adrenergic G-protein-coupled receptor. The comparison of the distance distribution functions for the simulation with the actual donor--acceptor distances in the receptor models suggested that two of the three receptor models were much more consistent with the receptor-mapping studies. These receptor-mapping studies gave support for the use of rhodopsin, rather than the bacteriorhodopsin template, for modeling G-protein-coupled receptors but also sounded a warning that agreement with binding data from site-directed mutagenesis experiments does not necessarily validate a receptor model.

  17. Production of beta-thujaplicin in Cupressus lusitanica suspension cultures fed with organic acids and monoterpenes. (United States)

    Zhao, J; Fujita, K; Sakai, K


    Effects of some organic acids and monoterpenes on production of beta-thujaplicin were studied in Cupressus lusitanica suspension cultures. The fungal elicitor-induced biosynthesis of beta-thujaplicin was promoted by the feedings of malate, pyruvate, fumarate, succinate, and acetate. These results suggest some relationships between acetate/pyruvate metabolism and beta-thujaplicin biosynthesis, or between tricarboxylic acid cycle and beta-thujaplicin biosynthesis. Feedings of C. lusitanica suspension cultures with some monoterpenes inhibited elicitor-triggered beta-thujaplicin biosynthesis, but 2-carene and terpinyl acetate feedings significantly improved the beta-thujaplicin production of C. lusitanica suspension cultures. These results indicate a possible involvement of terpinyl acetate and 2-carene in beta-thujaplicin biosynthesis, as well as potential uses of these monoterpenes in large-scale beta-thujaplicin production.

  18. Characterization of beta-adrenergic receptors in dispersed rat testicular interstitial cells

    Energy Technology Data Exchange (ETDEWEB)

    Poyet, P.; Labrie, F.


    Recent studies have shown that beta-adrenergic agents stimulate steroidogenesis and cyclic AMP formation in mouse Leydig cells in culture. To obtain information about the possible presence and the characteristics of a beta-adrenergic receptor in rat testicular interstitial cells, the potent beta-adrenergic antagonist (/sup 125/I)cyanopindolol (CYP) was used as ligand. Interstitial cells prepared by collagenase dispersion from rat testis were incubated with the ligand for 2 h at room temperature. (/sup 125/I)cyanopindolol binds to a single class of high affinity sites at an apparent KD value of 15 pM. A number of sites of 6,600 sites/cell is measured when 0.1 microM (-) propranolol is used to determine non-specific binding. The order of potency of a series of agonists competing for (/sup 125/I)cyanopindolol binding is consistent with the interaction of a beta 2-subtype receptor: zinterol greater than (-) isoproterenol greater than (-) epinephrine = salbutamol much greater than (-) norepinephrine. In addition, it was observed that the potency of a large series of specific beta 1 and beta 2 synthetic compounds for displacing (/sup 125/I)cyanopindolol in rat interstitial cells is similar to the potency observed for these compounds in a typical beta 2-adrenergic tissue, the rat lung. For example, the potency of zinterol, a specific beta 2-adrenergic agonist, is 10 times higher in interstitial cells and lung than in rat heart, a typical beta 1-adrenergic tissue. Inversely, practolol, a typical beta 1-antagonist, is about 50 times more potent in rat heart than in interstitial cells and lung.

  19. 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:; Ferreira-Alves, Dalton L. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte (Brazil). Inst. de Ciencias Biologicas. Dept. de Farmacologia


    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)

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

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


    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.

  1. 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: [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)


    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.

  2. Haloacetic acid and trihalomethane formation from the chlorination and bromination of aliphatic beta-dicarbonyl acid model compounds. (United States)

    Dickenson, Eric R V; Summers, R Scott; Croué, Jean-Philippe; Gallard, Hervé


    While it is known that resorcinol- and phenol-type aromatic structures within natural organic matter (NOM) react during drinking water chlorination to form trihalomethanes (THMs), limited studies have examined aliphatic-type structures as THM and haloacetic acid (HAA) precursors. A suite of aliphatic acid model compounds were chlorinated and brominated separately in controlled laboratory-scale batch experiments. Four and two beta-dicarbonyl acid compounds were found to be important precursors for the formation of THMs (chloroform and bromoform (71-91% mol/mol)), and dihaloacetic acids (DXAAs) (dichloroacetic acid and dibromoacetic acid (5-68% mol/mol)), respectively, after 24 h at pH 8. Based upon adsorbable organic halide formation, THMs and DXAAs, and to a lesser extent mono and trihaloacetic acids, were the majority (> 80%) of the byproducts produced for most of the aliphatic beta-dicarbonyl acid compounds. Aliphatic beta-diketone-acid-type and beta-keto-acid-type structures could be possible fast- and slow-reacting THM precursors, respectively, and aliphatic beta-keto-acid-type structures are possible slow-reacting DXAA precursors. Aliphatic beta-dicarbonyl acid moieties in natural organic matter, particularly in the hydrophilic fraction, could contribute to the significant formation of THMs and DXAAs observed after chlorination of natural waters.

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

    DEFF Research Database (Denmark)

    Vogel, W; Brakebusch, C; Fässler, R


    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...... with kinase activity or membrane-anchored proteins serving as coreceptors. In particular, the role of the collagen-binding integrins alpha(1)beta(1) or alpha(2)beta(1) in the DDR activation process is undefined. Here, we provide three lines of evidence suggesting that DDR1 signaling is distinct from integrin...... activation. First we demonstrate that the enzymatic activity of DDR1 is essential for receptor tyrosine phosphorylation. Collagen-induced DDR receptor autophosphorylation can be blocked either by a dominant negative mutant or by a preparation of recombinant extracellular domain. Second, we show DDR1 signals...

  4. beta-Arrestin 1 and 2 stabilize the angiotensin II type I receptor in distinct high-affinity conformations

    DEFF Research Database (Denmark)

    Sanni, S J; Hansen, J T; Bonde, M M;


    The angiotensin II type 1 (AT(1)) receptor belongs to family A of 7 transmembrane (7TM) receptors. The receptor has important roles in the cardiovascular system and is commonly used as a drug target in cardiovascular diseases. Interaction of 7TM receptors with G proteins or beta-arrestins often...

  5. Identification of Tctex2 beta, a novel dynein light chain family member that interacts with different transforming growth factor-beta receptors

    NARCIS (Netherlands)

    Meng, QingJun; Lux, Andreas; Holloschi, Andreas; Li, Jian; Hughes, John M. X.; Foerg, Tassilo; McCarthy, John E. G.; Heagerty, Anthony M.; Kioschis, Petra; Hafner, Mathias; Garland, John M.


    Endoglin is a membrane-inserted protein that is preferentially synthesized in angiogenic vascular endothelial and smooth muscle cells. Endoglin associates with members of the transforming growth factor-beta(TGF-beta) receptor family and has been identified as the gene involved in hereditary hemorrha

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

    Directory of Open Access Journals (Sweden)

    Julio E. Enders


    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.

  7. 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))


    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.

  8. Transforming growth factor-beta1 induces transforming growth factor-beta1 and transforming growth factor-beta receptor messenger RNAs and reduces complement C1qB messenger RNA in rat brain microglia. (United States)

    Morgan, T E; Rozovsky, I; Sarkar, D K; Young-Chan, C S; Nichols, N R; Laping, N J; Finch, C E


    Transforming growth factor-beta1 is a multifunctional peptide with increased expression during Alzheimer's disease and other neurodegenerative conditions which involve inflammatory mechanisms. We examined the autoregulation of transforming growth factor-beta1 and transforming growth factor-beta receptors and the effects of transforming growth factor-beta1 on complement C1q in brains of adult Fischer 344 male rats and in primary glial cultures. Perforant path transection by entorhinal cortex lesioning was used as a model for the hippocampal deafferentation of Alzheimer's disease. In the hippocampus ipsilateral to the lesion, transforming growth factor-beta1 peptide was increased >100-fold; the messenger RNAs encoding transforming growth factor-beta1, transforming growth factor-beta type I and type II receptors were also increased, but to a smaller degree. In this acute lesion paradigm, microglia are the main cell type containing transforming growth factor-beta1, transforming growth factor-beta type I and II receptor messenger RNAs, shown by immunocytochemistry in combination with in situ hybridization. Autoregulation of the transforming growth factor-beta1 system was examined by intraventricular infusion of transforming growth factor-beta1 peptide, which increased hippocampal transforming growth factor-beta1 messenger RNA levels in a dose-dependent fashion. Similarly, transforming growth factor-beta1 increased levels of transforming growth factor-beta1 messenger RNA and transforming growth factor-beta type II receptor messenger RNA (IC(50), 5pM) and increased release of transforming growth factor-beta1 peptide from primary microglia cultures. Interactions of transforming growth factor-beta1 with complement system gene expression are also indicated, because transforming growth factor-beta1 decreased C1qB messenger RNA in the cortex and hippocampus, after intraventricular infusion, and in cultured glia. These indications of autocrine regulation of transforming growth

  9. Estrogen receptor-beta colocalizes extensively with parvalbumin-labeled inhibitory neurons in the cortex, amygdala, basal forebrain, and hippocampal formation of intact and ovariectomized adult rats. (United States)

    Blurton-Jones, Mathew; Tuszynski, Mark H


    Estrogen has been reported to regulate the activity of gamma-aminobutyric acid (GABA)ergic interneurons within the hippocampus, basal forebrain, and hypothalamus of adult rodents. Although estrogen receptor-alpha bearing GABAergic interneurons have been identified previously, the neurotransmitter phenotype of cells that express the more recently characterized estrogen receptor-beta (ER-beta) has not been examined in vivo. We, therefore, have used fluorescent immunohistochemistry to further characterize the phenotype of ER-beta-bearing cells by double labeling for the GABAergic-associated calcium-binding protein, parvalbumin (PV). We find that a large proportion of ER-beta-immunoreactive cells within the cortex, amygdala, basal forebrain, and hippocampal formation of intact and ovariectomized (ovx) adult rats are PV-immunoreactive. Within the infralimbic, agranular insular, primary motor, parietal association, perirhinal, and lateral entorhinal cortices, an average of 95.6% +/- 0.8% (intact) and 94.5% +/- 1.4% (ovx) of all ER-beta-immunoreactive cells coexpress parvalbumin, and this proportion is strikingly similar across these diverse cortical regions. ER-beta/PV double-labeled cells represent 23.3% +/- 1.6% (intact) and 25.8% +/- 2.0% (ovx) of all PV-labeled cells within these regions. ER-beta/PV double-labeled cells are also observed within the lateral, accessory basal, and posterior cortical nuclei of the amygdala, and periamygdaloid cortex. Within the basal forebrain, 31.0% +/- 3.1% (intact) and 26.0% +/- 5.2 % (ovx) of ER-beta-immunoreactive cells coexpress PV. Almost all ER-beta-immunoreactive cells within the subiculum, a major output region of the hippocampal formation, double label for PV (intact = 97.2% +/- 2.8%; ovx = 100% +/- 0.0%). Thus, ER-beta exhibits extensive colocalization with a subclass of inhibitory neurons, suggesting a potential mechanism whereby estrogen can regulate neuronal excitability in diverse and broad brain regions by modulating

  10. Liquid chromatographic determination of beta-naphthoxyacetic acid in tomatoes. (United States)

    Gökmen, V; Acar, J


    An alternative high-performance liquid chromatographic method for the determination of beta-naphthoxyacetic acid (BNOA) in tomatoes is described. BNOA was extracted from tomatoes with acetone-dichloromethane (2:1). The extract was cleaned up by Bio-Beads S-X3 gel-permeation chromatography and by partitioning. A reversed-phase C18 column was used for HPLC analysis. The mobile phase was acetonitrile-2% acetic acid in water (50:50, v/v) pumped at a flow-rate of 1.0 ml/min. Retention time of BNOA was ca. 7 min with a percentage coefficient of variation of 0.71. Resolution of BNOA was good on the column. Percentage recoveries of BNOA were 79.5 +/- 6.82, 94.8 +/- 2.70 and 86.4 +/- 16.43 for the corresponding spiking levels of 0.5, 1.0 and 2.0 micrograms per g tomato, respectively. Analysis of 10 greenhouse tomato samples from local markets in Ankara showed no BNOA residue.

  11. Structure of the gene for human. beta. /sub 2/-adrenergic receptor: expression and promoter characterization

    Energy Technology Data Exchange (ETDEWEB)

    Emorine, L.J.; Marullo, S.; Delavier-Klutchko, C.; Kaveri, S.V.; Durieu-Trautmann, O.; Strosberg, A.D.


    The genomic gene coding for the human ..beta../sub 2/-adrenergic receptor (..beta../sub 2/AR) from A431 epidermoid cells has been isolated. Transfection of the gene into eukaryotic cells restores a fully active receptor/GTP-binding protein/adenylate cyclase complex with ..beta../sub 2/AR properties. Southern blot analyses with ..beta../sub 2/AR-specific probes show that a single ..beta../sub 2/AR gene is common to various human tissues and that its flanking sequences are highly conserved among humans and between man and rabbit, mouse, and hamster. Functional significance of these regions is supported by the presence of a promoter region (including mRNA cap sites, two TATA boxes, a CAAT box, and three G + C-rich regions that resemble binding sites for transcription factor Sp1) 200-300 base pairs 5' to the translation initiation codon. In the 3' flanking region, sequences homologous to glucocorticoid-response elements might be responsible for the increased expression of the ..beta../sub 2/AR gene observed after treatment of the transfected cells with hydrocortisone. In addition, 5' to the promoter region, an open reading frame encodes a 251-residue polypeptide that displays striking homologies with protein kinases and other nucleotide-binding proteins.

  12. 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.


    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.

  13. 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.


    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.

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

    NARCIS (Netherlands)

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


    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

  15. Estrogen receptors alpha and beta and the risk of open-angle glaucoma

    NARCIS (Netherlands)

    de Voogd, Simone; Wolfs, Roger C. W.; Jansonius, Nomdo M.; Uitterlinden, Andre G.; Pols, Huibert A. P.; Hofman, Albert; de Jong, Paulus T. V. M.


    Objective: To investigate whether polymorphisms in the estrogen receptor alpha (ESR1) and beta (ESR2) genes were a risk factor for open-angle glaucoma (OAG). Methods: Participants 55 years and older from the population-based Rotterdam Study underwent, at baseline and at follow-up, the same ophthalmi

  16. 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.


    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

  17. Fipronil-based photoaffinity probe for Drosophila and human beta 3 GABA receptors. (United States)

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


    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.

  18. Preparation and spectral investigation of inclusion complex of caffeic acid with hydroxypropyl-beta-cyclodextrin. (United States)

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


    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.

  19. Estrogen Receptor beta 2 Induces Hypoxia Signature of Gene Expression by Stabilizing HIF-1 alpha in Prostate Cancer


    Prasenjit Dey; Velazquez-Villegas, Laura A.; Michelle Faria; Anthony Turner; Philp Jonsson; Paul Webb; Cecilia Williams; Jan-Åke Gustafsson; Ström, Anders M.


    The estrogen receptor (ER) beta variant ER beta 2 is expressed in aggressive castration-resistant prostate cancer and has been shown to correlate with decreased overall survival. Genome-wide expression analysis after ER beta 2 expression in prostate cancer cells revealed that hypoxia was an overrepresented theme. Here we show that ER beta 2 interacts with and stabilizes HIF-1 alpha protein in normoxia, thereby inducing a hypoxic gene expression signature. HIF-1 alpha is known to stimulate met...

  20. 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: [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)


    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Hill, D.A.


    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.

  2. Engagement of fatty acids with Toll-like receptor 2 drives interleukin-1beta production via the ASC/caspase 1 pathway in monosodium urate monohydrate crystal-induced gouty arthritis.

    NARCIS (Netherlands)

    Joosten, L.A.B.; Netea, M.G.; Mylona, E.; Koenders, M.I.; Malireddi, R.K.; Oosting, M.; Stienstra, R.; Veerdonk, F.L. van de; Stalenhoef, A.F.H.; Giamarellos-Bourboulis, E.J.; Kanneganti, T.D.; Meer, J.W.M. van der


    OBJECTIVE: The concept that intraarticular crystals of uric acid by themselves trigger episodes of painful gouty arthritis is inconsistent with the clinical reality. Patients with large deposits of monosodium urate monohydrate (MSU) crystals (tophi) do not necessarily experience gouty attacks. In fa

  3. 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


    alpha V beta 2 in the lysate, and likewise, depleting the lysate of Ti alpha V beta with anti-V beta 2 mAb did not reduce the amount of Ti alpha V beta 8. Comodulation experiments showed that V beta 8 and V beta 2 did not comodulate with each other. Furthermore, functional tests demonstrated that Tc......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...... 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...

  4. alpha7 Nicotinic acetylcholine receptor knockout selectively enhances ethanol-, but not beta-amyloid-induced neurotoxicity. (United States)

    de Fiebre, Nancyellen C; de Fiebre, Christopher M


    The alpha7 subtype of nicotinic acetylcholine receptor (nAChR) has been implicated as a potential site of action for two neurotoxins, ethanol and the Alzheimer's disease related peptide, beta-amyloid. Here, we utilized primary neuronal cultures of cerebral cortex from alpha7 nAChR null mutant mice to examine the role of this receptor in modulating the neurotoxic properties of subchronic, "binge" ethanol and beta-amyloid. Knockout of the alpha7 nAChR gene selectively enhanced ethanol-induced neurotoxicity in a gene dosage-related fashion. Susceptibility of cultures to beta-amyloid induced toxicity, however, was unaffected by alpha7 nAChR gene null mutation. Further, beta-amyloid did not inhibit the binding of the highly alpha7-selective radioligand, [(125)I]alpha-bungarotoxin. On the other hand, in studies in Xenopus oocytes ethanol efficaciously inhibited alpha7 nAChR function. These data suggest that alpha7 nAChRs modulate the neurotoxic effects of binge ethanol, but not the neurotoxicity produced by beta-amyloid. It is hypothesized that inhibition of alpha7 nAChRs by ethanol provides partial protection against the neurotoxic properties of subchronic ethanol.

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


    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.

  6. Effect of extracellular pH on recombinant alpha1beta2gamma2 and alpha1beta2 GABAA receptors. (United States)

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


    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.

  7. Beta-Adrenergic Receptors and Mechanisms in Asthma: The New Long-Acting Beta-Agonists

    Directory of Open Access Journals (Sweden)

    Robert G Townley


    Full Text Available The objective is to review β-adrenergic receptors and mechanisms in the immediate and late bronchial reaction in asthma and the new long-acting β-agonist. This will be discussed in light of the controversy of the potential adverse effect of regular use of long-acting β-agonists. We studied the effect of formoterol on the late asthmatic response (LAR and airway inflammation in guinea-pigs. Formoterol suppressed the LAR, antigen-induced airway inflammation and hyperresponsiveness, although isoproterenol failed to inhibit these parameters. β-Adrenergic hyporesponsiveness, and cholinergic and a- adrenergic hyperresponsiveness have been implicated in the pathogenesis of asthma. A decrease in β-adrenoreceptor function can result either from exogenously administered β-agonist or from exposure to allergens resulting in a late bronchial reaction. There is increasing evidence that eosinophils, macrophages, and lymphocytes which are of primary importance in the late bronchial reaction are also modulated by β2- adrenoreceptors. In functional studies of guinea-pig or human isolated trachea and lung parenchyma, PAF and certain cytokines significantly reduced the potency of isoproterenol to reverse methacholine- or histamine-induced contraction. The effect of glucocorticoids on pulmonary β-adrenergic receptors and responses suggests an important role for glucocorticoids to increase β-adrenergic receptors and responsiveness.

  8. 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)


    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.

  9. 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;


    The complete amino acid sequences of chicken and turkey beta 2-microglobulins have been determined by analyses of tryptic, V8-proteolytic and cyanogen bromide fragments, and by N-terminal sequencing. Mass spectrometric analysis of chicken beta 2-microglobulin supports the sequence-derived Mr of 11......,048. The higher apparent Mr obtained for the avian beta 2-microglobulins as compared to human beta 2-microglobulin by SDS-PAGE is not understood. Chicken and turkey beta 2-microglobulin consist of 98 residues and deviate at seven positions: 60, 66, 74-76, 78 and 82. The chicken and turkey sequences are identical...... 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...

  10. Beta-glucosidases and nucleic acids encoding same

    DEFF Research Database (Denmark)


    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...

  11. Ligand-dependent inhibition of beta-catenin/TCF signaling by androgen receptor. (United States)

    Chesire, Dennis R; Isaacs, William B


    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

  12. Identification of tetrahydro-beta-carboline-3-carboxylic acid in foodstuffs, human urine and human milk. (United States)

    Adachi, J; Mizoi, Y; Naito, T; Ogawa, Y; Uetani, Y; Ninomiya, I


    1-Methyl-1,2,3,4-tetrahydro-beta-carboline-3-carboxylic acid (MTCA) and 1,2,3,4-tetrahydro-beta-carboline-3-carboxylic acid (TCCA), both precursors of mutagenic N-nitroso compounds (N-nitrosamines, 1-methyl-2-nitroso-1,2,3,4-tetrahydro-beta-carboline-3-carboxylic acid and 2-nitroso-1,2,3,4-tetrahydro-beta-carboline-3-carboxylic acid), were detected in various food-stuffs, urine from healthy human subjects and human milk. A purification procedure, involving a chemically-bonded material followed by HPLC combined with fluorometric detection, was used for the quantitative determination of these compounds, allowing the separation of two diastereoisomers of MTCA. An HPLC and mass spectrometry method was also developed for their identification. Comparing the concentration of MTCA and TCCA in fermented products and raw materials suggested that tetrahydro-beta-carbolines may have been produced through fermentation or by condensation of tryptophan and acetaldehyde formed from ethanol added as a food preservative. This is the first report of excretion of tetrahydro-beta-carbolines in human urine and human milk. A comparison of the concentrations of tetrahydro-beta-carbolines in urine from human infants and human milk indicates that tetrahydro-beta-carbolines may be synthesized endogenously in humans. A possible pathway of tryptophan metabolism in plants and animals is presented.

  13. 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


    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

  14. Tissue-specific expression of betaKlotho and fibroblast growth factor (FGF) receptor isoforms determines metabolic activity of FGF19 and FGF21. (United States)

    Kurosu, Hiroshi; Choi, Mihwa; Ogawa, Yasushi; Dickson, Addie S; Goetz, Regina; Eliseenkova, Anna V; Mohammadi, Moosa; Rosenblatt, Kevin P; Kliewer, Steven A; Kuro-o, Makoto


    The fibroblast growth factor (FGF) 19 subfamily of ligands, FGF19, FGF21, and FGF23, function as hormones that regulate bile acid, fatty acid, glucose, and phosphate metabolism in target organs through activating FGF receptors (FGFR1-4). We demonstrated that Klotho and betaKlotho, homologous single-pass transmembrane proteins that bind to FGFRs, are required for metabolic activity of FGF23 and FGF21, respectively. Here we show that, like FGF21, FGF19 also requires betaKlotho. Both FGF19 and FGF21 can signal through FGFR1-3 bound by betaKlotho and increase glucose uptake in adipocytes expressing FGFR1. Additionally, both FGF19 and FGF21 bind to the betaKlotho-FGFR4 complex; however, only FGF19 signals efficiently through FGFR4. Accordingly, FGF19, but not FGF21, activates FGF signaling in hepatocytes that primarily express FGFR4 and reduces transcription of CYP7A1 that encodes the rate-limiting enzyme for bile acid synthesis. We conclude that the expression of betaKlotho, in combination with particular FGFR isoforms, determines the tissue-specific metabolic activities of FGF19 and FGF21.

  15. Pancreatic Beta Cell G-Protein Coupled Receptors and Second Messenger Interactions: A Systems Biology Computational Analysis. (United States)

    Fridlyand, Leonid E; Philipson, Louis H


    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

  16. 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;


    The extracellular domain of receptor type protein tyrosine phosphatase beta (RPTP beta) exhibits striking sequence similarity with a soluble, rat brain chondroitin sulfate proteoglycan (3F8 PG). Immunoprecipitation experiments of cells transfected with RPTP beta expression vector and metabolically...... labeled with [35S]sulfate and [35S]methionine indicate that the transmembrane form of RPTP beta is indeed a chondroitin sulfate proteoglycan. The 3F8 PG is therefore a variant form composed of the entire extracellular domain of RPTP beta probably generated by alternative RNA splicing. Previous...

  17. Molecular pharmacology of 4-substituted glutamic acid analogues at ionotropic and metabotropic excitatory amino acid receptors

    DEFF Research Database (Denmark)

    Bräuner-Osborne, Hans; Nielsen, B; Stensbøl, T B;


    using rat brain ionotropic glutamate receptors, and in functional assays using cloned metabotropic glutamate (mGlu) receptors. As a notable result of these studies, (2S,4R)-4-methylglutamic acid and (2S,4S)-4-methylglutamic acid were shown to be selective for kainic acid receptors and mGlu receptors......The pharmacology of (2S,4R)-4-methylglutamic acid, (2S,4S)-4-methylglutamic acid and (S)- and (R)-4-methyleneglutamic acids (obtained in high chemical and enantiomeric purity from racemic 4-methyleneglutamic acid by chiral HPLC using a Crownpak CR(+) column), was examined in binding experiments...... (subtypes 1alpha and 2), respectively, whereas (S)-4-methyleneglutamic acid showed high but rather non-selective affinity for the (RS)-2-amino-3-(3-hydroxy-5-methylisoxazol-4-yl)propionic acid (AMPA), kainic acid, NMDA and mGlu receptors (subtypes 1alpha and 2). Although none of the compounds were specific...

  18. 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


    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......Previously metal-ion sites have been used as structural and functional probes in seven transmembrane receptors (7TM), but as yet all the engineered sites have been inactivating. Based on presumed agonist interaction points in transmembrane III (TM-III) and -VII of the beta(2)-adrenergic receptor......, in this paper we construct an activating metal-ion site between the amine-binding Asp-113 in TM-III-or a His residue introduced at this position-and a Cys residue substituted for Asn-312 in TM-VII. No increase in constitutive activity was observed in the mutant receptors. Signal transduction was activated...

  19. Photoaffinity labeling of alpha- and beta- scorpion toxin receptors associated with rat brain sodium channel. (United States)

    Darbon, H; Jover, E; Couraud, F; Rochat, H


    Azido nitrophenylaminoacetyl [125I]iodo derivative of toxin II from Centruroides suffusus suffusus, a beta-toxin, and azido nitrophenylaminoacetyl [125I]iodo derivative of toxin V from Leiurus quinquestriatus quinquestriatus, an alpha-toxin, have been covalently linked after binding to their receptor sites that are related to the voltage sensitive sodium channel present in rat brain synaptosomes. Both derivatives labeled two polypeptides of 253000 +/- 20000 and 35000 +/- 2000 mol. wt. Labeling was blocked for each derivative by a large excess of the corresponding native toxin but no cross inhibition was obtained. These results suggest that both alpha - and beta - scorpion toxin receptors are located on or near the same two membrane polypeptides which may be part of the voltage dependent sodium channel.

  20. 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)


    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.

  1. 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)


    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.

  2. BGL4 beta-glucosidase and nucleic acids encoding the same (United States)

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


    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.

  3. 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)


    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.

  4. 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)


    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.

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


    Ignacio Rodríguez; Jesualdo Fuentes; Valery Valencia; Fanny Cuesta González; Gabriel Bedoya Berrío; Sergio Parra


    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, gener...

  6. 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


    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...

  7. Quinoline based receptor in fluorometric discrimination of carboxylic acids

    Directory of Open Access Journals (Sweden)


    Full Text Available Quinoline and naphthalene-based fluororeceptors 1 and 2 have been designed and synthesized for detection of hydroxy carboxylic acids in less polar solvents. The receptor 1 shows monomer emission quenching followed by excimer emission upon hydrogen bond-mediated complexation of carboxylic acids. The excimer emission distinguishes aromatic dicarboxylic acids from aliphatic dicarboxylic acids and even long chain aliphatic dicarboxylic acids from short chain aliphatic dicarboxylic acids. The receptor 1 is found to be selective for citric acid with a strong excimer emission in CHCl3. On the contrary, the receptor 2 exhibited less binding constant value and did not form any excimer upon complexation with the same acids under similar conditions. This established the role of quinoline ring nitrogen in binding with the acids.

  8. Estrogenic potencies of resorcylic acid lactones and 17 beta-estradiol in female rats. (United States)

    Everett, D J; Perry, C J; Scott, K A; Martin, B W; Terry, M K


    Uterotrophic response in sexually immature female rats has been used to rank the relative estrogenic potencies of six resorcylic acid lactones (RALs) and to compare their activities with that of 17 beta-estradiol. On oral administration, the estrogenic potency relative to 17 beta-estradiol is as follows: 7 alpha-zearalenol, 10 times less; zeranol, 150 times less; taleranol, 350 times less; zearalanone, 400 times less; zearalenone, 650 times less; 7 beta-zearalenol, 3500 times less. On subcutaneous administration, zeranol is 500 times less estrogenic than 17 beta-estradiol.

  9. 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


    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.

  10. 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;


    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...... chemokine receptor (CXCR)3 was unaltered. Conversely, at 9-12 h after the most recent IFN-beta injection, CCR4, CCR5 and CCR7 expressions were unaltered, while CXCR3 expression was reduced. CD4(+) T-cell surface expression of CCR4 was significantly lower in untreated MS patients compared with healthy...... volunteers. Of the plasma chemokines, only CXCL10 was increased by IFN-beta treatment; CCL3, CCL4, CCL5 and CXCL9 were unaltered. CCR5 mRNA expression in blood mononuclear cells correlated with the expression of T-helper type 1 (Th1)-associated genes whereas CCR4 and CCR7 mRNA expression correlated with Th2...

  11. NMDA receptor subunit composition determines beta-amyloid-induced neurodegeneration and synaptic loss


    Tackenberg, C; Grinschgl, S; Trutzel, A; Santuccione, A C; Frey, M C; Konietzko, U; Grimm, J.; Brandt, R.; Nitsch, R M


    Aggregates of amyloid-beta (Aβ) and tau are hallmarks of Alzheimer's disease (AD) leading to neurodegeneration and synaptic loss. While increasing evidence suggests that inhibition of N-methyl--aspartate receptors (NMDARs) may mitigate certain aspects of AD neuropathology, the precise role of different NMDAR subtypes for Aβ- and tau-mediated toxicity remains to be elucidated. Using mouse organotypic hippocampal slice cultures from arcAβ transgenic mice combined with Sindbis virus-mediated ex...

  12. Effect of {beta}{sub 1} adrenergic receptor blockade on myocardial blood flow and vasodilatory capacity

    Energy Technology Data Exchange (ETDEWEB)

    Boettcher, M.; Czernin, J.; Sun, K. [Univ. of California, Los Angeles, CA (United States)] [and others


    The {beta}{sub 1} receptor blockade reduces cardiac work and may thereby lower myocardial blood flow (MBF) at rest. The effect of {beta}{sub 1} receptor blockade on hyperemic MBF is unknown. To evaluate the effect of selective {beta}{sub 1} receptor blockade on MBF at rest and during dipyridamole induced hyperemia, 10 healthy volunteers (8 men, 2 women, mean age 24 {+-} 5 yr) were studied using {sup 13}N-ammonia PET (two-compartment model) under control conditions and again during metoprolol (50 mg orally 12 hr and 1 hr before the study). The resting rate pressure product (6628 {+-} 504 versus 5225 {+-} 807) and heart rate (63 {+-} 6-54 {plus_minus} 5 bpm) declined during metoprolol (p < 0.05). Similarly, heart rate and rate pressure product declined from the baseline dipyridamole study to dipyridamole plus metoprolol (p < 0.05). Resting MBF declined in proportion to cardiac work by approximately 20% from 0.61 {+-} 0.09-0.51 {+-} 0.10 ml/g/min (p < 0.05). In contrast, hyperemic MBF increased when metoprolol was added to dipyridamole (1.86 {plus_minus} 0.27 {+-} 0.45 ml/g/min; p<0.05). The decrease in resting MBF together with the increase in hyperemic MBF resulted in a significant increase in the myocardial flow reserve during metoprolol (3.14 {+-} 0.80-4.61 {+-} 0.68; p<0.01). The {beta}{sub 1} receptor blockade increases coronary vasodilatory capacity and myocardial flow reserve. However, the mechanisms accounting for this finding remain uncertain. 32 refs., 2 figs., 2 tabs.

  13. Increased mandibular condylar growth in mice with estrogen receptor beta deficiency


    Yosuke, Kamiya; JING, Chen; Manshan, Xu; Achint, Utreja; Thomas, Choi; Hicham, Drissi; Sunil, Wadhwa


    Temporomandibular joint (TMJ) disorders predominantly afflict women of childbearing age, suggesting a role for female hormones in the disease process. In long bones, estrogen acting via estrogen receptor beta (ERβ) inhibits axial skeletal growth in female mice. However, the role of ERβ in the mandibular condyle is largely unknown. We hypothesize that female ERβ deficient mice will have increased mandibular condylar growth compared with wild type (WT) female mice. This study examined female 7-...

  14. Estrogen dissociates Tau and alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor subunit in postischemic hippocampus. (United States)

    Cardona-Gómez, Gloria Patricia; Arango-Davila, Cesar; Gallego-Gómez, Juan Carlos; Barrera-Ocampo, Alvaro; Pimienta, Hernan; Garcia-Segura, Luis Miguel


    During cerebral ischemia, part of the damage associated with the hyperactivation of glutamate receptors results from the hyperphosphorylation of the microtubule-associated protein Tau. Previous studies have shown that estradiol treatment reduces neural damage after cerebral ischemia. Here, we show that transient occlusion of the middle cerebral artery results in the hyperphosphorylation of Tau and in a significant increase in the association of Tau with glycogen synthase kinase-3beta and alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid type glutamate receptor subunits 2/3 in the hippocampus. Estradiol treatment decreased hippocampal injury, inhibited glycogen synthase kinase-3beta and decreased the hyperphosphorylation of Tau and the interaction of Tau with glycogen synthase kinase-3beta and alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor. These findings suggest that ischemia produces a strong association between Tau and alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor, and estradiol can exert at least part of its neuroprotective activity through inhibition of glycogen synthase kinase-3beta.

  15. beta-estradiol influences differentiation of hippocampal neurons in vitro through an estrogen receptor-mediated process. (United States)

    Audesirk, T; Cabell, L; Kern, M; Audesirk, G


    We utilized morphometric analysis of 3 day cultures of hippocampal neurons to determine the effects of both estradiol and the synthetic estrogen receptor modulator raloxifene on several parameters of neuronal growth and differentiation. These measurements included survival, neurite production, dendrite number, and axon and dendrite length and branching. 17 beta-Estradiol (10 nM) selectively stimulated dendrite branching; this effect was neither mimicked by alpha-estradiol, nor blocked by the estrogen receptor antagonist ICI 182780. The selective estrogen receptor modulator raloxifene (100 nM) neither mimicked nor reversed the effects of estradiol on dendritic branching. Western immunoblotting for the alpha and beta subtypes of estrogen receptor revealed the presence of alpha, but not beta, estrogen receptors in our hippocampal cultures. There is growing recognition of the effects of 17 beta-estradiol on neuronal development and physiology, with implications for brain sexual dimorphism, plasticity, cognition, and the maintenance of cognitive function during aging. The role of estradiol in hippocampal neuronal differentiation and function has particular implications for learning and memory. These data support the hypothesis that 17 beta-estradiol is acting via alpha estrogen receptors in influencing hippocampal development in vitro. Raloxifene, prescribed to combat osteoporosis in post-menopausal women, is a selective estrogen receptor modulator with tissue-specific agonist/antagonist properties. Because raloxifene had no effect on dendritic branching, we hypothesize that it does not interact with the alpha estrogen receptor in this experimental paradigm.

  16. Heterocyclic acetamide and benzamide derivatives as potent and selective beta3-adrenergic receptor agonists with improved rodent pharmacokinetic profiles. (United States)

    Goble, Stephen D; Wang, Liping; Howell, K Lulu; Bansal, Alka; Berger, Richard; Brockunier, Linda; DiSalvo, Jerry; Feighner, Scott; Harper, Bart; He, Jiafang; Hurley, Amanda; Hreniuk, Donna; Parmee, Emma; Robbins, Michael; Salituro, Gino; Sanfiz, Anthony; Streckfuss, Eric; Watkins, Eloisa; Weber, Ann E; Struthers, Mary; Edmondson, Scott D


    A series of amide derived beta(3)-adrenergic receptor (AR) agonists is described. The discovery and optimization of several series of compounds derived from 1, is used to lay the SAR foundation for second generation beta(3)-AR agonists for the treatment of overactive bladder.

  17. Coordinated induction of bile acid detoxification and alternative elimination in mice: role of FXR-regulated organic solute transporter-alpha/beta in the adaptive response to bile acids. (United States)

    Zollner, Gernot; Wagner, Martin; Moustafa, Tarek; Fickert, Peter; Silbert, Dagmar; Gumhold, Judith; Fuchsbichler, Andrea; Halilbasic, Emina; Denk, Helmut; Marschall, Hanns-Ulrich; Trauner, Michael


    The bile acid receptor farnesoid X receptor (FXR) is a key regulator of hepatic defense mechanisms against bile acids. A comprehensive study addressing the role of FXR in the coordinated regulation of adaptive mechanisms including biosynthesis, metabolism, and alternative export together with their functional significance is lacking. We therefore fed FXR knockout (FXR(-/-)) mice with cholic acid (CA) and ursodeoxycholic acid (UDCA). Bile acid synthesis and hydroxylation were assessed by real-time RT-PCR for cytochrome P-450 (Cyp)7a1, Cyp3a11, and Cyp2b10 and mass spectrometry-gas chromatography for determination of bile acid composition. Expression of the export systems multidrug resistance proteins (Mrp)4-6 in the liver and kidney and the recently identified basoalteral bile acid transporter, organic solute transporter (Ost-alpha/Ost-beta), in the liver, kidney, and intestine was also investigated. CA and UDCA repressed Cyp7a1 in FXR(+/+) mice and to lesser extents in FXR(-/-) mice and induced Cyp3a11 and Cyp2b10 independent of FXR. CA and UDCA were hydroxylated in both genotypes. CA induced Ost-alpha/Ost-beta in the liver, kidney, and ileum in FXR(+/+) but not FXR(-/-) mice, whereas UDCA had only minor effects. Mrp4 induction in the liver and kidney correlated with bile acid levels and was observed in UDCA-fed and CA-fed FXR(-/-) animals but not in CA-fed FXR(+/+) animals. Mrp5/6 remained unaffected by bile acid treatment. In conclusion, we identified Ost-alpha/Ost-beta as a novel FXR target. Absent Ost-alpha/Ost-beta induction in CA-fed FXR(-/-) animals may contribute to increased liver injury in these animals. The induction of bile acid hydroxylation and Mrp4 was independent of FXR but could not counteract liver toxicity sufficiently. Limited effects of UDCA on Ost-alpha/Ost-beta may jeopardize its therapeutic efficacy.

  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. The expression and localization of estrogen receptor beta in hyperplastic and neoplastic prostate lesions

    Directory of Open Access Journals (Sweden)

    Fejsa-Levakov Aleksandra


    Full Text Available Background/Aim. Benign acini in benign prostatic hyperplasia (BPH are lined with pseudostratified cylindrical epithelium with a continuous basal cell layer. Adenocarcinoma of the prostate is the most common cancer in men. High gradus-prostatic intraepithelial neoplasia (HGPIN lesions precede invasive cancer. Prostate adenocarcinoma (PCa implies a complete absence of basal cells and stromal invasion by malignant acini. Estrogen receptor (ER is located in nuclei of acinar basal and secretory cells and partially in stromal cells. The aim of this research was to demonstrate and localize ER in BPH and in PCa of different Gleason scores. Considering literature data for ER-beta expression in different morphologic prostate lesions, it is assumed that there is expression of ER-beta in most moderately differentiated PCa, and that the observed receptor expression is lost with increasing of the Gleason score. Methods. Four groups of patients were formed: the control with BPH and three experimental groups with PCa of different grades and scores, according to the Gleason grading system. The patients were male of various ages suspected of PCa, based on clinical and laboratory parameters. The study was conducted in a period 2010-2012. None of the patients received prior hormonal therapy. Sextant byopsies with BPH and PCa were treated for ER-beta (Novocastra. Localization and intensity of ER-beta expression is reported through the score: 0 = zero; 1 = 66%. Positive fibroblasts and endothelial cells are used for comparison. Results. ER-beta expression in acinar epithelial cells was the weakest in welldifferentiated adenocarcinoma. A decline of ER-beta expression was noticed in malignant lesions of the prostate vs benign ones. Less differentiated adenocarcinomas showed a decrease of ER-beta expression in basal and in the secretory cells. ERbeta expression in basal cells was stronger than in secretory ones in BPH and well-differentiated adenocarcinoma. Conclusion

  20. 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;


    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......-isoxazolyl]propionic acid (AMOA). Using these AMPA receptor ligands as leads, a series of compounds have been developed as tools for further elucidation of the structural requirements for activation and blockade of AMPA receptors. The synthesized compounds have been tested for activity at ionotropic...... excitatory amino acid (EAA) receptors using receptor binding and electrophysiological techniques, and for activity at metabotropic EAA receptors using second messenger assays. Compounds 1 and 4 were essentially inactive. (RS)-2-Amino-3-[3-(2-carboxyethyl)-5-methyl-4-isoxazolyl]propionic acid (ACMP, 2...

  1. Expression of transforming growth factor-beta receptors types II and III within various cells in the rat periodontium. (United States)

    Gao, J; Symons, A L; Bartold, P M


    This study reports the immunohistochemical localization of TGF-beta receptor type II (T beta R-II) and type III (T beta R-III) in cells of the forming periodontal ligament (PDL) in rat first molar roots. Mandibular periodontium was obtained from 3, 6 and 12-wk-old rats. This represented tissue from the initial, pre-mature and post-mature stages of root and periodontal development, respectively. Mandibular bone chips and molar roots were used to isolate osteoblasts, fibroblasts and cementoblasts. Cells were obtained using a 2-step trypsinization and explant technique, and cultured in Dulbecco's modification of Eagle's medium (DMEM) under routine cell culture conditions. Cells were cultured on coverslips for the purpose of detecting TGF-beta receptors, and compared with whole tissue sections using the same detection method. Cells which stained positively for T beta R-II and T beta R-III on both paraffin sections and cultured cell slides were counted. Both receptors were expressed in the various periodontal tissue compartments. PDL fibroblasts, cementoblasts and osteoblasts were stained positively for T beta R-II and T beta R-III. Endothelial cells were noted to be positive for T beta R-II only. T beta R-II was more widely distributed in cells than T beta R-III, but T beta R-III was extensively localized in the extracellular matrix. Both receptors were expressed on the cell membrane and also localized in the cytoplasm. The findings for paraffin sections were consistent with the immunohistochemical staining of cultured cells. The percentage of cells which stained positively for T beta R-II was greater (approximately 85%) than that for T beta R-III (approximately 60%) in all major types of the PDL cells on both paraffin sections and cultured cell slides. Extensive location of TGF-beta receptors in both cells and extracellular matrix suggests that several binding sites are available for TGF-beta s to interact with target cells during development and following maturation

  2. 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: [Steacie Institute for Molecular Sciences, National Research Council Canada, Ottawa, ON, Canada K1A 0R6 (Canada); Pezacki, John Paul, E-mail: [Steacie Institute for Molecular Sciences, National Research Council Canada, Ottawa, ON, Canada K1A 0R6 (Canada)


    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.

  3. 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: [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)


    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.

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

    Directory of Open Access Journals (Sweden)

    Jose M G Vilar


    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.

  5. Recent developments in the catalytic asymmetric synthesis of alpha- and beta-amino acids. (United States)

    Ma, Jun-An


    The stereoselective synthesis of amino acids is of great importance for the construction of optically active natural products and pharmaceuticals. Apart from enzymes, a broad repertoire of chiral reagents, auxiliaries, and catalysts can be used for the formation of amino acids. Asymmetric reactions using catalytic amounts of chiral molecules provide efficient methods for the generation of optically active proteinogenic and nonproteinogenic amino acids. This minireview collects recent work on catalytic asymmetric synthesis of alpha- and beta-amino acids.

  6. beta-Keratins in crocodiles reveal amino acid homology with avian keratins. (United States)

    Ye, Changjiang; Wu, Xiaobing; Yan, Peng; Amato, George


    The DNA sequences encoding beta-keratin have been obtained from Marsh Mugger (Crocodylus palustris) and Orinoco Crocodiles (Crocodylus intermedius). Through the deduced amino acid sequence, these proteins are rich in glycine, proline and serine. The central region of the proteins are composed of two beta-folded regions and show a high degree of identity with beta-keratins of aves and squamates. This central part is thought to be the site of polymerization to build the framework of beta-keratin filaments. It is believed that the beta-keratins in reptiles and birds share a common ancestry. Near the C-terminal, these beta-keratins contain a peptide rich in glycine-X and glycine-X-X, and the distinctive feature of the region is some 12-amino acid repeats, which are similar to the 13-amino acid repeats in chick scale keratin but absent from avian feather keratin. From our phylogenetic analysis, the beta-keratins in crocodile have a closer relationship with avian keratins than the other keratins in reptiles.

  7. Exercise-induced muscle damage is not attenuated by beta-hydroxy-beta-methylbutyrate and alpha-ketoisocaproic acid supplementation. (United States)

    Nunan, David; Howatson, Glyn; van Someren, Ken A


    The purpose of this study was to examine the effects of combined oral beta-hydroxy-beta-methylbutyrate (HMB) and alpha-ketoisocaproic acid (KIC) supplementation on indices of exercise-induced muscle damage (EIMD) after an acute bout of eccentric-biased exercise. Fourteen male subjects were allocated to 2 groups: a placebo group (3 g.d corn flour, N = 7) or an HMB + KIC group (3 g.d HMB and 0.3 g.d KIC, N = 7). Supplementation commenced 11 days before a 40-minute bout of downhill running and continued for 3 days post-exercise. Delayed-onset muscle soreness, mid-thigh girth, knee extensor range of motion, serum creatine kinase (CK) activity, and isometric and concentric torque were assessed pre-exercise and at 24, 48, and 72 hours post-exercise. Delayed-onset muscle soreness, CK activity, and isometric and concentric torque all changed over the 72-hour period (p < 0.05); however, HMB + KIC had no significant effect on any of the indices of muscle damage. Although 14 days HMB and KIC supplementation did not attenuate indices of EIMD after an acute bout of unaccustomed eccentric-biased exercise, there was a trend for a more rapid rate of recovery in isometric and isokinetic muscle function. beta-hydroxy-beta-methylbutyrate and KIC may therefore provide limited benefit in the recovery of muscle function after EIMD in untrained subjects or after unaccustomed exercise.

  8. PGE2 receptor EP2 mediates the antagonistic effect of COX-2 on TGF-beta signaling during mammary tumorigenesis. (United States)

    Tian, Maozhen; Schiemann, William P


    The molecular mechanisms that enable cyclooxygenase-2 (COX-2) and its mediator prostaglandin E2 (PGE2) to inhibit transforming growth factor-beta (TGF-beta) signaling during mammary tumorigenesis remain unknown. We show here that TGF-beta selectively stimulated the expression of the PGE2 receptor EP2, which increased normal and malignant mammary epithelial cell (MEC) invasion, anchorage-independent growth, and resistance to TGF-beta-induced cytostasis. Mechanistically, elevated EP2 expression in normal MECs inhibited the coupling of TGF-beta to Smad2/3 activation and plasminogen activator inhibitor-1 (PAI1) expression, while EP2 deficiency in these same MECs augmented Smad2/3 activation and PAI expression stimulated by TGF-beta. Along these lines, engineering malignant MECs to lack EP2 expression prevented their growth in soft agar, restored their cytostatic response to TGF-beta, decreased their invasiveness in response to TGF-beta, and potentiated their activation of Smad2/3 and expression of PAI stimulated by TGF-beta. More important, we show that COX-2 or EP2 deficiency both significantly decreased the growth, angiogenesis, and pulmonary metastasis of mammary tumors produced in mice. Collectively, this investigation establishes EP2 as a potent mediator of the anti-TGF-beta activities elicited by COX-2/PGE2 in normal and malignant MECs. Our findings also suggest that pharmacological targeting of EP2 receptors may provide new inroads to antagonize the oncogenic activities of TGF-beta during mammary tumorigenesis.-Tian, M., Schiemann, W. P. PGE2 receptor EP2 mediates the antagonistic effect of COX-2 on TGF-beta signaling during mammary tumorigenesis.

  9. 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


    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.

  10. Dopamine D2-like receptors are expressed in pancreatic beta cells and mediate inhibition of insulin secretion. (United States)

    Rubí, Blanca; Ljubicic, Sanda; Pournourmohammadi, Shirin; Carobbio, Stefania; Armanet, Mathieu; Bartley, Clarissa; Maechler, Pierre


    Dopamine signaling is mediated by five cloned receptors, grouped into D1-like (D1 and D5) and D2-like (D2, D3 and D4) families. We identified by reverse transcription-PCR the presence of dopamine receptors from both families in INS-1E insulin-secreting cells as well as in rodent and human isolated islets. D2 receptor expression was confirmed by immunodetection revealing localization on insulin secretory granules of INS-1E and primary rodent and human beta cells. We then tested potential effects mediated by the identified receptors on beta cell function. Dopamine (10 microM) and the D2-like receptor agonist quinpirole (5 microM) inhibited glucose-stimulated insulin secretion tested in several models, i.e. INS-1E beta cells, fluorescence-activated cell-sorted primary rat beta cells, and pancreatic islets of rat, mouse, and human origin. Insulin exocytosis is controlled by metabolism coupled to cytosolic calcium changes. Measurements of glucose-induced mitochondrial hyperpolarization and ATP generation showed that dopamine and D2-like agonists did not inhibit glucose metabolism. On the other hand, dopamine decreased cell membrane depolarization as well as cytosolic calcium increases evoked by glucose stimulation in INS-1E beta cells. These results show for the first time that dopamine receptors are expressed in pancreatic beta cells. Dopamine inhibited glucose-stimulated insulin secretion, an effect that could be ascribed to D2-like receptors. Regarding the molecular mechanisms implicated in dopamine-mediated inhibition of insulin release, our results point to distal steps in metabolism-secretion coupling. Thus, the role played by dopamine in glucose homeostasis might involve dopamine receptors, expressed in pancreatic beta cells, modulating insulin release.

  11. 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


    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...

  12. Control of yeast mating signal transduction by a mammalian. beta. sub 2 -adrenergic receptor and G sub s. alpha. subunit

    Energy Technology Data Exchange (ETDEWEB)

    King, K.; Caron, M.G.; Lefkowitz, R.J. (Duke Univ. Medical Center, Durham, NC (USA)); Dohlman, H.G.; Thorner, J. (Univ. of California, Berkeley (USA))


    To facilitate functional and mechanistic studies of receptor-G protein interactions by expression of the human {beta}{sub 2}-adrenergic receptor (h{beta}-AR) has been expressed in Saccharomyces cerevisiae. This was achieved by placing a modified h{beta}-AR gene under control of the galactose-inducible GAL1 promoter. After induction by galactose, functional h{beta}-AR was expressed at a concentration several hundred times as great as that found in any human tissue. As determined from competitive ligand binding experiments, h{beta}-AR expressed in yeast displayed characteristic affinities, specificity, and stereoselectivity. Partial activation of the yeast pheromone response pathway by {beta}-adrenergic receptor agonists was achieved in cells coexpressing h{beta}-AR and a mammalian G protein (G{sub s}) {alpha} subunit - demonstrating that these components can couple to each other and to downstream effectors when expressed in yeast. This in vivo reconstitution system provides a new approach for examining ligand binding and G protein coupling to cell surface receptors.

  13. Phytoestrogens induce differential estrogen receptor alpha- or Beta-mediated responses in transfected breast cancer cells. (United States)

    Harris, D M; Besselink, E; Henning, S M; Go, V L W; Heber, D


    Increased intake of phytoestrogens may be associated with a lower risk of cancer in the breast and several other sites, although there is controversy surrounding this activity. One of the mechanisms proposed to explain the activity of phytoestrogens is their ability to bind and activate human estrogen receptor alpha (ERalpha) and human estrogen receptor beta (ERbeta). Nine phytoestrogens were tested for their ability to transactivate ERalpha or ERbeta at a range of doses. Mammary adenocarcinoma (MCF-7) cells were co-transfected with either ERalpha or ERbeta, and an estrogen-response element was linked to a luciferase reporter gene. Dose-dependent responses were compared with the endogenous ligand 17beta-estradiol. Purified genistein, daidzein, apigenin, and coumestrol showed differential and robust transactivation of ERalpha- and ERbeta-induced transcription, with an up to 100-fold stronger activation of ERbeta. Equol, naringenin, and kaempferol were weaker agonists. When activity was evaluated against a background of 0.5 nM 17beta-estradiol, the addition of genistein, daidzein, and resveratrol superstimulated the system, while kaempferol and quercetin were antagonists at the highest doses. This transfection assay provides an excellent model to evaluate the activation of ERalpha and ERbeta by different phytoestrogens in a breast cancer context and can be used as a screening bioassay tool to evaluate the estrogenic activity of extracts of herbs and foods.

  14. Ghrelin secretion stimulated by {beta}1-adrenergic receptors in cultured ghrelinoma cells and in fasted mice. (United States)

    Zhao, Tong-Jin; Sakata, Ichiro; Li, Robert Lin; Liang, Guosheng; Richardson, James A; Brown, Michael S; Goldstein, Joseph L; Zigman, Jeffrey M


    Ghrelin, an octanoylated peptide hormone produced in the stomach, rises dramatically in mouse plasma during chronic severe calorie deprivation, an event that is essential to maintain life. The mechanism for this increase is not understood. Here, we study the control of ghrelin secretion in tissue culture cells derived from mice bearing ghrelinomas induced by a tissue-specific SV40 T-antigen transgene. We found that the ghrelin-secreting cells express high levels of mRNA encoding beta(1)-adrenergic receptors. Addition of norepinephrine or epinephrine to the culture medium stimulated ghrelin secretion, and this effect was blocked by atenolol, a selective beta(1)-adrenergic antagonist. When WT mice were treated with reserpine to deplete adrenergic neurotransmitters from sympathetic neurons, the fasting-induced increase in plasma ghrelin was blocked. Inhibition was also seen following atenolol administration. We conclude that ghrelin secretion during fasting is induced by adrenergic agents released by sympathetic neurons and acting directly on beta(1) receptors on the ghrelin-secreting cells of the stomach.

  15. 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


    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.

  16. 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


    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.

  17. 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


    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.

  18. Association of polymorphisms in the beta-2 adrenergic receptor gene with fracture risk and bone mineral density

    NARCIS (Netherlands)

    Veldhuis-Vlug, A G; Oei, L; Souverein, P C; Tanck, M W T; Rivadeneira, F; Zillikens, M C; Kamphuisen, P W; Maitland-van der Zee, A H; de Groot, M C H; Hofman, A; Uitterlinden, A G; Fliers, E; de Boer, A; Bisschop, P H


    Signaling through the beta-2 adrenergic receptor (B2AR) on the osteoblast influences bone remodeling in rodents. In the B2AR gene, three polymorphisms influence receptor function. We show that these polymorphisms are not associated with fracture risk or bone mineral density in the UCP, Rotterdam Stu

  19. Association of polymorphisms in the beta-2 adrenergic receptor gene with fracture risk and bone mineral density

    NARCIS (Netherlands)

    A.G. Veldhuis-Vlug; L. Oei (Ling); P. Souverein (Patrick); M.W.T. Tanck (Michael); F. Rivadeneira Ramirez (Fernando); M.C. Zillikens (Carola); P.W. Kamphuisen; A-H. Maitland-van der Zee (Anke-Hilse); M.C.H. de Groot; A. Hofman (Albert); A.G. Uitterlinden (André); E. Fliers (Eric); A.C. de Boer (Anthonius); P.H. Bisschop


    textabstractSummary: Signaling through the beta-2 adrenergic receptor (B2AR) on the osteoblast influences bone remodeling in rodents. In the B2AR gene, three polymorphisms influence receptor function. We show that these polymorphisms are not associated with fracture risk or bone mineral density in t

  20. Association of polymorphisms in the beta-2 adrenergic receptor gene with fracture risk and bone mineral density

    NARCIS (Netherlands)

    Veldhuis-Vlug, A. G.; Oei, L.; Souverein, P. C.; Tanck, M. W T; Rivadeneira, F.; Zillikens, M. C.; Kamphuisen, P. W.; Maitland - van der Zee, A. H.; de Groot, M. C H; Hofman, A.; Uitterlinden, A. G.; Fliers, E.; de Boer, A.; Bisschop, P. H.


    Summary: Signaling through the beta-2 adrenergic receptor (B2AR) on the osteoblast influences bone remodeling in rodents. In the B2AR gene, three polymorphisms influence receptor function. We show that these polymorphisms are not associated with fracture risk or bone mineral density in the UCP, Rott

  1. PI3K is involved in PDGF-beta receptor upregulation post-PDGF-BB treatment in mouse HSC. (United States)

    Lechuga, Carmen G; Hernández-Nazara, Zamira H; Hernández, Elizabeth; Bustamante, Marcia; Desierto, Gregory; Cotty, Adam; Dharker, Nachiket; Choe, Moran; Rojkind, Marcos


    Increased expression of PDGF-beta receptors is a landmark of hepatic stellate cell activation and transdifferentiation into myofibroblasts. However, the molecular mechanisms that regulate the fate of the receptor are lacking. Recent studies suggested that N-acetylcysteine enhances the extracellular degradation of PDGF-beta receptor by cathepsin B, thus suggesting that the absence of PDGF-beta receptors in quiescent cells is due to an active process of elimination and not to a lack of expression. In this communication we investigated further molecular mechanisms involved in PDGF-beta receptor elimination and reappearance after incubation with PDGF-BB. We showed that in culture-activated hepatic stellate cells there is no internal protein pool of receptor, that the protein is maximally phosphorylated by 5 min and completely degraded after 1 h by a lysosomal-dependent mechanism. Inhibition of receptor autophosphorylation by tyrphostin 1296 prevented its degradation, but several proteasomal inhibitors had no effect. We also showed that receptor reappearance is time and dose dependent, being more delayed in cells treated with 50 ng/ml (48 h) compared with 10 ng/ml (24 h).

  2. IM-1662 Attenuates Radiation-Induced Fibroblast Differentiation through Restoration of TGF-beta type III Receptor

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sa Rah; Ahn, Ji Yeon; Kim, Mi Hyoung; Lim, Min Jin; Lee, Sae Loom; Yun, Yeon Sook; Song, Jie Young [Korea Institue of Radiological and Medical Sciences, Seoul (Korea, Republic of)


    Although pulmonary fibrosis occurs 5-20% of lung cancer patients who underwent radiotherapy, clinically standard treatment for fibrotic disease has not been developed yet. Among fibrosis mediating factors such as transforming growth factor-beta (TGF-beta), connective tissue growth factor (CTGF), platelet derived growth factor (PDGF), fibroblast growth factor (FGF), interleukin-13 (IL-13), IL-4, interferon-gamma (IFN-gamma), and tumor necrosis factor (TNF-alpha), TGF-beta is considered as a critical mediator in normal wound healing as well as pathological fibrogenic processes. The TGF-beta transmits signals either directly or indirectly through types I, II and III (TbetaRI, II, and III) receptor complexes and activates downstream Smad signaling. The type III TGF-beta receptor (TbetaRIII or betaglycan) is a transmembrane proteoglycan without a functional kinase domain, and is regarded as a co-receptor to increase the affinity of ligand binding to TbetaRII. In addition, TbetaRIII act as a regulator in cell migration, invasion and cell growth in cancer models. However, in contrast to a great number of studies about TGF-beta ligand and TbetaRII signaling, the relationship between TGF-beta and TbetaRIII (or betaglycan) remains largely unknown. In this study, we searched for a new compound which inhibited TGF-beta responses using cell-based chemical screening and investigated the effects of the novel compound on radiation induced myofibroblast differentiation. We suggest that a novel small molecule, pyrazolopyrimidine compound IM-1662, can act as an anti-fibrotic agent through inhibiting expression of TGF-beta receptor type I and type II whereas, preserving the levels of TbetaRIII which seems to act as a negative regulator in TGF-beta signaling

  3. Indices of brain beta-adrenergic receptor signal transduction in the learned helplessness animal model of depression. (United States)

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


    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.

  4. 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;


    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...

  5. Identification of (beta-carboxyethyl)-rhodanine derivatives exhibiting peroxisome proliferator-activated receptor gamma activity. (United States)

    Choi, Jiwon; Ko, Yoonae; Lee, Hui Sun; Park, Yun Sun; Yang, Young; Yoon, Sukjoon


    We applied an improved virtual screening scheme combining ligand-centric and receptor-centric methods for the identification of a new series of PPARgamma agonists known as (beta-carboxyethyl)-rhodanine derivatives which include a thiazolidin-based core structure, 2-thioxo-thiazolidine-4-one. An in vitro assay confirmed the nanomolar binding affinity in one of the (beta-carboxyethyl)-rhodanine derivatives, SP1818. It showed a PPARgamma agonistic activity similar to that of a known PPARgamma drug, pioglitazone, in a cell-based transactivation assay. Furthermore, the structure-activity relationships of the rhodanine derivatives were investigated through comparative molecular field analysis. We also characterized the inconsistency between the in vitro binding affinity and cell-based transactivation ability by using a set of property-based molecular descriptors. The binding mode analysis provided new insight concerning their agonistic effect on PPARgamma.

  6. Complex pharmacology of free fatty acid receptors


    Milligan, Graeme; Shimpukade, Bharat; Ulven, Trond; Hudson, Brian D.


    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 simple competitive agonism or antagonism by ligands interacting with the orthosteric binding site of the receptor to incorporate concepts of allosteric agonism, allosteric modulation, signaling bias, c...

  7. A role for fungal {beta}-glucans and their receptor Dectin-1 in the induction of autoimmune arthritis in genetically susceptible mice. (United States)

    Yoshitomi, Hiroyuki; Sakaguchi, Noriko; Kobayashi, Katsuya; Brown, Gordon D; Tagami, Tomoyuki; Sakihama, Toshiko; Hirota, Keiji; Tanaka, Satoshi; Nomura, Takashi; Miki, Ichiro; Gordon, Siamon; Akira, Shizuo; Nakamura, Takashi; Sakaguchi, Shimon


    A combination of genetic and environmental factors can cause autoimmune disease in animals. SKG mice, which are genetically prone to develop autoimmune arthritis, fail to develop the disease under a microbially clean condition, despite active thymic production of arthritogenic autoimmune T cells and their persistence in the periphery. However, in the clean environment, a single intraperitoneal injection of zymosan, a crude fungal beta-glucan, or purified beta-glucans such as curdlan and laminarin can trigger severe chronic arthritis in SKG mice, but only transient arthritis in normal mice. Blockade of Dectin-1, a major beta-glucan receptor, can prevent SKG arthritis triggered by beta-glucans, which strongly activate dendritic cells in vitro in a Dectin-1-dependent but Toll-like receptor-independent manner. Furthermore, antibiotic treatment against fungi can prevent SKG arthritis in an arthritis-prone microbial environment. Multiple injections of polyinosinic-polycytidylic acid double-stranded RNA also elicit mild arthritis in SKG mice. Thus, specific microbes, including fungi and viruses, may evoke autoimmune arthritis such as rheumatoid arthritis by stimulating innate immunity in individuals who harbor potentially arthritogenic autoimmune T cells as a result of genetic anomalies or variations.

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

    CERN Document Server

    Sharley, John N


    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...

  9. Metabolic response to various beta-adrenoceptor agonists in beta3-adrenoceptor knockout mice: evidence for a new beta-adrenergic receptor in brown adipose tissue. (United States)

    Preitner, F; Muzzin, P; Revelli, J P; Seydoux, J; Galitzky, J; Berlan, M; Lafontan, M; Giacobino, J P


    The beta3-adrenoceptor plays an important role in the adrenergic response of brown and white adipose tissues (BAT and WAT). In this study, in vitro metabolic responses to beta-adrenoceptor stimulation were compared in adipose tissues of beta3-adrenoceptor knockout and wild type mice. The measured parameters were BAT fragment oxygen uptake (MO2) and isolated white adipocyte lipolysis. In BAT of wild type mice (-)-norepinephrine maximally stimulated MO2 4.1+/-0.8 fold. Similar maximal stimulations were obtained with beta1-, beta2- or beta3-adrenoceptor selective agonists (dobutamine 5.1+/-0.3, terbutaline 5.3+/-0.3 and CL 316,243 4.8+/-0.9 fold, respectively); in BAT of beta3-adrenoceptor knockout mice, the beta1- and beta2-responses were fully conserved. In BAT of wild type mice, the beta1/beta2-antagonist and beta3-partial agonist CGP 12177 elicited a maximal MO2 response (4.7+/-0.4 fold). In beta3-adrenoceptor knockout BAT, this response was fully conserved despite an absence of response to CL 316,243. This unexpected result suggests that an atypical beta-adrenoceptor, distinct from the beta1-, beta2- and beta3-subtypes and referred to as a putative beta4-adrenoceptor is present in BAT and that it can mediate in vitro a maximal MO2 stimulation. In isolated white adipocytes of wild type mice, (-)-epinephrine maximally stimulated lipolysis 12.1+/-2.6 fold. Similar maximal stimulations were obtained with beta1-, beta2- or beta3-adrenoceptor selective agonists (TO509 12+/-2, procaterol 11+/-3, CL 316,243 11+/-3 fold, respectively) or with CGP 12177 (7.1+/-1.5 fold). In isolated white adipocytes of beta3-adrenoceptor knockout mice, the lipolytic responses to (-)epinephrine, to the beta1-, beta2-, beta3-adrenoceptor selective agonists and to CGP 12177 were almost or totally depressed, whereas those to ACTH, forskolin and dibutyryl cyclic AMP were conserved.

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

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


    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.

  11. Electrical Stimulation Decreases Coupling Efficiency Between Beta-Adrenergic Receptors and Cyclic AMP Production in Cultured Muscle Cells (United States)

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


    Electrical stimulation of skeletal muscle cells in culture is an effective way to simulate the effects of muscle contraction and its effects on gene expression in muscle cells. Expression of the beta-adrenergic receptor and its coupling to cyclic AMP synthesis are important components of the signaling system that controls muscle atrophy and hypertrophy, and the goal of this project was to determine if electrical stimulation altered the beta-adrenergic response in muscle cells. Chicken skeletal muscle cells that had been grown for seven days in culture were subjected to electrical stimulation for an additional two days at a pulse frequency of 0.5 pulses/sec and a pulse duration of 200 msec. At the end of this two-day stimulation period, beta-adrenergic receptor population was measured by the binding of tritium-labeled CGP-12177 to muscle cells, and coupling to cAMP synthesis was measured by Radioimmunoassay (RIA) after treating the cells for 10 min with the potent (beta)AR agonist, isoproterenol. The number of beta adrenergic receptors and the basal levels of intracellular cyclic AMP were not affected by electrical stimulation. However, the ability of these cells to synthesize cyclic AMP was reduced by approximately 50%. Thus, an enhanced level of contraction reduces the coupling efficiency of beta-adrenergic receptors for cyclic AMP production.

  12. Roles of oestrogen receptors alpha and beta in behavioural neuroendocrinology: beyond Yin/Yang. (United States)

    Rissman, E F


    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.

  13. 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: [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)


    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.

  14. 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;


    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...

  15. Identifying the receptor subtype selectivity of retinoid X and retinoic acid receptors via quantum mechanics. (United States)

    Tsuji, Motonori; Shudo, Koichi; Kagechika, Hiroyuki


    Understanding and identifying the receptor subtype selectivity of a ligand is an important issue in the field of drug discovery. Using a combination of classical molecular mechanics and quantum mechanical calculations, this report assesses the receptor subtype selectivity for the human retinoid X receptor (hRXR) and retinoic acid receptor (hRAR) ligand-binding domains (LBDs) complexed with retinoid ligands. The calculated energies show good correlation with the experimentally reported binding affinities. The technique proposed here is a promising method as it reveals the origin of the receptor subtype selectivity of selective ligands.

  16. Distinct ErbB2 receptor populations differentially interact with beta1 integrin in breast cancer cell models (United States)

    Toscani, Andrés Martín; Sampayo, Rocío G.; Barabas, Federico Martín; Fuentes, Federico; Simian, Marina


    ErbB2 is a member of the ErbB family of tyrosine kinase receptors that plays a major role in breast cancer progression. Located at the plasma membrane, ErbB2 forms large clusters in spite of the presence of growth factors. Beta1 integrin, membrane receptor of extracellular matrix proteins, regulates adhesion, migration and invasiveness of breast cancer cells. Physical interaction between beta1 integrin and ErbB2 has been suggested although published data are contradictory. The aim of the present work was to study the interaction between ErbB2 and beta1 integrin in different scenarios of expression and activation. We determined that beta1 integrin and ErbB2 colocalization is dependent on the expression level of both receptors exclusively in adherent cells. In suspension cells, lack of focal adhesions leave integrins free to diffuse on the plasma membrane and interact with ErbB2 even at low expression levels of both receptors. In adherent cells, high expression of beta1 integrin leaves unbound receptors outside focal complexes that diffuse within the plasma membrane and interact with ErbB2 membrane domains. Superresolution imaging showed the existence of two distinct populations of ErbB2: a major population located in large clusters and a minor population outside these structures. Upon ErbB2 overexpression, receptors outside large clusters can freely diffuse at the membrane and interact with integrins. These results reveal how expression levels of beta1 integrin and ErbB2 determine their frequency of colocalization and show that extracellular matrix proteins shape membrane clusters distribution, regulating ErbB2 and beta1 integrin activity in breast cancer cells. PMID:28306722

  17. 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


    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

  18. 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


    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.

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

    Khedr, Alaa


    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. 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.


    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.

  1. Effect of chronic metoprolol and coronary occlusion (CO) on cardiac beta receptor density in cats

    Energy Technology Data Exchange (ETDEWEB)

    Lathers, C.M.; Spivey, W.H.; Levin, R.M.


    The effect of metoprolol (M) on beta receptor density (BRD) was examined. M (5 mg/kg, p.o., b.i.d.) was given for 2 and 8 wks prior to CO of the left anterior descending artery (LAD) at its origin. BRD, determined by binding of /sup 3/H-dihydroalprenol, was examined in the myocardium (LA = left atrium, RA = right atrium, LV1 = proximal LAD distribution, LV = 2 distal LAD distribution, LV3 = posterior left ventricle, RV = right ventricle, and S = septum. A 2 factor ANOVA followed by simple effect and Newman-Keuls post hoc tests revealed that M produced no effect in BRD in LA, RA, LV2, or S. M increased BRD in LV1, LV3, and RV after 2 wk when compared to no M. In addition, BRD in LV3 and RV were also greater at 2 wk than after 8 wk M. The data indicate that there are regional differences in the beta adrenergic receptor densities among the areas of the heart and within the left ventricle. Chronic dosing with M produced increased BRD in only some of the areas of the heart. These differences may be related to functional differences in the various areas of the heart after CO.

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

    Directory of Open Access Journals (Sweden)

    Ignacio Rodríguez


    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.

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

    LENUS (Irish Health Repository)

    Hogan, A M


    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

  4. A novel acid-stable, acid-active beta-galactosidase potentially suited to the alleviation of lactose intolerance. (United States)

    O'Connell, Shane; Walsh, Gary


    Extracellular beta-galactosidase produced by a strain of Aspergillus niger van Tiegh was purified to homogeneity using a combination of gel filtration, ion-exchange, chromatofocusing, and hydrophobic interaction chromatographies. The enzyme displayed a temperature optimum of 65 degrees C and a low pH optimum of between 2.0 and 4.0. The monomeric glycosylated enzyme displayed a molecular mass of 129 kDa and an isoelectric point of 4.7. Protein database similarity searching using mass spectrometry-derived sequence data indicate that the enzyme shares homology with a previously sequenced A. niger beta-galactosidase. Unlike currently commercialised products, the enzyme displayed a high level of stability when exposed to simulated gastric conditions in vitro, retaining 68+/-2% of original activity levels. This acid-stable, acid-active beta-galactosidase was formulated, along with a neutral beta-galactosidase from Kluyveromyces marxianus DSM5418, in a novel two-segment capsule system designed to ensure delivery of enzymes of appropriate physicochemical properties to both stomach and small intestine. When subjected to simulated full digestive tract conditions, the twin lactase-containing capsule hydrolyzed, per unit activity, some 3.5-fold more lactose than did the commercial supplemental enzyme. The acid-stable, acid-active enzyme, along with the novel two-segment delivery system, may prove beneficial in the more effective treatment of lactose intolerance.

  5. 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. (United States)

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


    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.

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

    DEFF Research Database (Denmark)

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


    (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...

  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


    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. Estrogen receptor beta participate in the regulation of metabolizm of extracellular matrix in estrogen alpha negative breast cancer. (United States)

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


    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.

  9. Crystal Structure of Staphylococcal Enterotoxin G (SEG) in Complex with a Mouse T-cell Receptor Beta Chain

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, M.M.; Robinson, H.; Cho, S.; De Marzi, M. C.; Kerzic, M. C.; Mariuzza, R. A.; Malchiodi, E. L.


    Superantigens (SAgs) are bacterial or viral toxins that bind MHC class II (MHC-II) molecules and T-cell receptor (TCR) in a nonconventional manner, inducing T-cell activation that leads to inflammatory cytokine production, which may result in acute toxic shock. In addition, the emerging threat of purpura fulminans and community-associated meticillin-resistant Staphylococcus aureus emphasizes the importance of a better characterization of SAg binding to their natural ligands that may allow the development of reagents to neutralize their action. The three-dimensional structure of the complex between a mouse TCR {beta} chain (mV{beta}8.2) and staphylococcal enterotoxin G (SEG) at 2.0 {angstrom} resolution revealed a binding site that does not conserve the 'hot spots' present in mV{beta}8.2-SEC2, mV{beta}8.2-SEC3, mV{beta}8.2-SEB, and mV{beta}8.2-SPEA complexes. Analysis of the mV{beta}8.2-SEG interface allowed us to explain the higher affinity of this complex compared with the others, which may account for the early activation of T-cells bearing mV{beta}8.2 by SEG. This mode of interaction between SEG and mV{beta}8.2 could be an adaptive advantage to bestow on the pathogen a faster rate of colonization of the host.

  10. G protein-coupled receptor kinase 2 and beta-arrestins are recruited to FSH receptor in stimulated rat primary Sertoli cells. (United States)

    Marion, Sébastien; Kara, Elodie; Crepieux, Pascale; Piketty, Vincent; Martinat, Nadine; Guillou, Florian; Reiter, Eric


    FSH-receptor (FSH-R) signaling is regulated by agonist-induced desensitization and internalization. It has been shown, in a variety of overexpression systems, that G protein-coupled receptor kinases (GRKs) phosphorylate the activated FSH-R, promote beta-arrestin recruitment and ultimately lead to internalization. The accuracy of this mechanism has not yet been demonstrated in cells expressing these different molecules at physiological levels. Using sucrose gradient fractionation, we show that FSH induces the recruitment of the endogenous GRK 2 and beta-arrestin 1/2 from the cytoplasm to the plasma membrane of rat primary Sertoli cells. As assessed by ligand binding, the FSH-R was found expressed in the fractions where GRK 2 and beta-arrestins were recruited upon FSH treatment. In addition, the endogenous beta-arrestin 1 was found dephosphorylated in an agonist-dependent manner. Finally, a significant FSH-binding activity was co-immunoprecipitated with the endogenous beta-arrestins from agonist-stimulated but not from untreated Sertoli cell extracts. This FSH-R interaction with beta-arrestins was sustained for up to 30 min. In conclusion, our data strongly suggest that the GRK/beta-arrestin machinery plays a physiologically relevant role in the regulation of the FSH signaling.

  11. The beta2 adrenergic receptor Gln27Glu polymorphism affects insulin resistance in patients with heart failure: possible modulation by choice of beta blocker. (United States)

    Vardeny, Orly; Detry, Michelle A; Moran, John J M; Johnson, Maryl R; Sweitzer, Nancy K


    Insulin resistance is prevalent in heart failure (HF) patients, and beta2 adrenergic receptors (beta2-AR) are involved in glucose homeostasis. We hypothesized that beta2-AR Gln27Glu and Arg16Gly polymorphisms affect insulin resistance in HF patients, and we explored if effects of beta2-AR polymorphisms on glucose handling are modified by choice of beta blocker. We studied 30 nondiabetic adults with HF and a history of systolic dysfunction; 15 were receiving metoprolol succinate, and 15 were receiving carvedilol. We measured fasting glucose, insulin, and insulin resistance, and we determined beta2-AR genotypes at codons 27 and 16. The cohort was insulin resistant with a mean HOMA-IR score of 3.4 (95% CI, 2.3 to 4.5; normal value, 1.0). Patients with the Glu27Glu genotype exhibited higher insulin and HOMA-IR compared to individuals carrying a Gln allele (P = 0.019). Patients taking carvedilol demonstrated lower insulin resistance if also carrying a wild-type allele at codon 27 (fasting insulin, 9.8 +/- 10.5 versus 20.5 +/- 2.1 for variant, P = 0.072; HOMA-IR, 2.4 +/- 2.7 versus 5.1 +/- 0.6, P = 0.074); those on metoprolol succinate had high insulin resistance irrespective of genotype. The beta2-AR Glu27Glu genotype may be associated with higher insulin concentrations and insulin resistance in patients with HF. Future studies are needed to confirm whether treatment with carvedilol may be associated with decreased insulin and insulin resistance in beta2-AR codon 27 Gln carriers.

  12. Activation of a GTP-binding protein and a GTP-binding-protein-coupled receptor kinase (beta-adrenergic-receptor kinase-1) by a muscarinic receptor m2 mutant lacking phosphorylation sites. (United States)

    Kameyama, K; Haga, K; Haga, T; Moro, O; Sadée, W


    A mutant of the human muscarinic acetylcholine receptor m2 subtype (m2 receptor), lacking a large part of the third intracellular loop, was expressed and purified using the baculovirus/insect cell culture system. The mutant was not phosphorylated by beta-adrenergic-receptor kinase, as expected from the previous assignment of phosphorylation sites to the central part of the third intracellular loop. However, the m2 receptor mutant was capable of stimulating beta-adrenergic-receptor-kinase-1-mediated phosphorylation of a glutathione S-transferase fusion protein containing the m2 phosphorylation sites in an agonist-dependent manner. Both mutant and wild-type m2 receptors reconstituted with the guanine-nucleotide-binding regulatory proteins (G protein), G(o) and G(i)2, displayed guanine-nucleotide-sensitive high-affinity agonist binding, as assessed by displacement of [3H]quinuclidinyl-benzilate binding with carbamoylcholine, and both stimulated guanosine 5'-3-O-[35S]thiotriphosphate ([35S]GTP[S]) binding in the presence of carbamoylcholine and GDP. The Ki values of carbamoylcholine effects on [3H]quinuclidinyl-benzilate binding were indistinguishable for the mutant and wild-type m2 receptors. Moreover, the phosphorylation of the wild-type m2 receptor by beta-adrenergic-receptor kinase-1 did not affect m2 interaction with G proteins as assessed by the binding of [3H]quinuclidinyl benzilate or [35S]GTP[S]. These results indicate that (a) the m2 receptor serves both as an activator and as a substrate of beta-adrenergic-receptor kinase, and (b) a large part of the third intracellular loop of the m2 receptor does not contribute to interaction with G proteins and its phosphorylation by beta-adrenergic-receptor kinase does not uncouple the receptor and G proteins in reconstituted lipid vesicles.

  13. Receptor-binding properties of the peptides corresponding to the beta-endorphin-like sequence of human immunoglobulin G. (United States)

    Zav'yalov, V P; Zaitseva, O R; Navolotskaya, E V; Abramov, V M; Volodina EYu; Mitin, Y V


    The decapeptide H2N-Ser-Leu-Thr-Cys-Leu-Val-Lys-Gly-Phe-Tyr-COOH (termed immunorphin) corresponding to the sequence 364-373 of the CH3 domain of the human immunoglobulin G1 Eu heavy chain and displaying a 43% identity with the antigenic determinant of beta-endorphin was synthesized. Immunorphin was found to compete with 125I-beta-endorphin for high-affinity receptors on murine peritoneal macrophages (K = 2.5 +/- 0.9 x 10(-9) M) and with 3H-morphin for receptors on murine thymocytes (Ki = 2.7 +/- 0.6 x 10(-9) M) and murine macrophages (Ki = 5.9 +/- 0.7 x 10(-9) M). In particular two types of receptors to 125I-beta-endorphin with Kd1 = 6.1 +/- 0.6 x 10(-9) M and Kd2 = 3.1 +/- 0.2 x 10(-8) M were revealed on macrophages. The second type of receptors interacted with 125I-beta-endorphin, 3H-Met-enkephalin, 3H-Leu-enkephalin and 3H-morphin; the first displayed reactivity with 125I-beta-endorphin, 3H-morphin and immunorphin. The first type receptors are not present on murine brain cells nor are inhibited by naloxone. A minimum fragment of immunorphin practically completely retaining its inhibitory activity in the competition tests with 125I-beta-endorphin for common receptors on thymocytes was found to correspond to the tetrapeptide H2N-Lys-Gly-Phe-Tyr-COOH (Ki = 5.6 +/- 0.5 x 10(-9) M).

  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


    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. Binding of (/sup 3/H)ethyl-. beta. -carboline-3-carboxylate to brain benzodiazepine receptors. Effect of drugs and anions

    Energy Technology Data Exchange (ETDEWEB)

    Williams, E.F.; Paul, S.M.; Rice, K.C.; Skolnick, P. (National Institutes of Health, Bethesda, MD (USA)); Cain, M. (Wisconsin Univ., Milwaukee (USA). Dept. of Chemistry)


    It is reported that in contrast to the changes in affinity of (/sup 3/H)benzodiazepines elicited by halide ions, barbiturates, and pyrazolopyridines, the apparent affinity of ..beta..-(/sup 3/H)CCE (ethyl-..beta..-carboline-3-carboxylate) is unaffected by these agents. Furthermore, Scatchard analysis of ..beta..-(/sup 3/H)CCE binding to cerebral cortical and cerebellar membranes revealed a significantly greater number of binding sites than was observed with either (/sup 3/H)diazepam or (/sup 3/H)flunitazepam, suggesting that at low concentrations benzodiazepines selectively label a subpopulation of the receptors labelled with ..beta..-(/sup 3/H)CCE. Alternatively, ..beta..-(/sup 3/H)CCE may bind to sites that are distinct from those labelled with (/sup 3/H)-benzodiazepines.

  16. 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


    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.

  17. Mu-opiate receptor and Beta-endorphin expression in nerve endings and keratinocytes in human skin. (United States)

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


    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.

  18. Mechanisms of transcriptional activation of the mouse claudin-5 promoter by estrogen receptor alpha and beta. (United States)

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


    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.

  19. RT-PCR and Northern blot analysis in search for a putative Paramecium beta-adrenergic receptor. (United States)

    Płatek, A; Wiejak, J; Wyroba, E


    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.

  20. Heterologous activation of protein kinase C stimulates phosphorylation of delta-opioid receptor at serine 344, resulting in beta-arrestin- and clathrin-mediated receptor internalization

    DEFF Research Database (Denmark)

    Xiang, B; Yu, G H; Guo, J


    , and ionomycin resulted in DOR internalization that required phosphorylation of Ser-344. Expression of dominant negative beta-arrestin and hypertonic sucrose treatment blocked PMA-induced DOR internalization, suggesting that PKC mediates DOR internalization via a beta-arrestin- and clathrin-dependent mechanism......The purpose of the current study is to investigate the effect of opioid-independent, heterologous activation of protein kinase C (PKC) on the responsiveness of opioid receptor and the underlying molecular mechanisms. Our result showed that removing the C terminus of delta opioid receptor (DOR...... phosphorylation could inhibit PKC-catalyzed heterologous DOR phosphorylation and subsequent internalization. These data demonstrate that the responsiveness of opioid receptor is regulated by both PKC and GRK through agonist-dependent and agonist-independent mechanisms and PKC-mediated receptor phosphorylation...

  1. Synthesis and antibacterial properties of beta-diketone acrylate bioisosteres of pseudomonic acid A. (United States)

    Bennett, I; Broom, N J; Cassels, R; Elder, J S; Masson, N D; O'Hanlon, P J


    A series of beta-diketone acrylate bioisosteres 4 of pseudomonic acid A 1 have been synthesized and evaluated for their ability to inhibit bacterial isoleucyl-tRNA synthetase and act as antibacterial agents. A number of analogues have excellent antibacterial activity. Selected examples were shown to afford good blood levels and to be effective in a murine infection model.

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

    DEFF Research Database (Denmark)

    Goncalves de Azavedo, Carlos M. B. P.; Watterson, Kenneth R; Wargent, Ed T;


    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 structu...

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

    DEFF Research Database (Denmark)

    Andersen, G; Wegner, L; Yanagisawa, K


    Peroxisome proliferator activated receptor-gamma coactivator-1beta (PGC-1beta) is a recently identified homologue of the tissue specific coactivator PGC-1alpha, a coactivator of transcription factors such as the peroxisome proliferators activated receptors and nuclear respiratory factors. PGC-1......alpha is involved in adipogenesis, mitochondrial biogenesis, fatty acid beta oxidation, and hepatic gluconeogenesis....

  4. Enzymatic synthesis of enantiopure alpha- and beta-amino acids by phenylalanine aminomutase-catalysed amination of cinnamic acid derivatives. (United States)

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


    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.

  5. 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: [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)


    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.

  6. 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

  7. Suppression of human monocyte interleukin-1beta production by ajulemic acid, a nonpsychoactive cannabinoid. (United States)

    Zurier, Robert B; Rossetti, Ronald G; Burstein, Sumner H; Bidinger, Bonnie


    Oral administration of ajulemic acid (AjA), a cannabinoid acid devoid of psychoactivity, reduces joint tissue damage in rats with adjuvant arthritis. Because interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNFalpha) are central to the progression of inflammation and joint tissue injury in patients with rheumatoid arthritis, we investigated human monocyte IL-1beta and TNFalpha responses after the addition of AjA to cells in vitro. Peripheral blood and synovial fluid monocytes (PBM and SFM) were isolated from healthy subjects and patients with inflammatory arthritis, respectively, treated with AjA (0-30 microM) in vitro, and then stimulated with lipopolysaccharide. Cells were harvested for mRNA, and supernatants were collected for cytokine assay. Addition of AjA to PBM and SFM in vitro reduced both steady-state levels of IL-1beta mRNA and secretion of IL-1beta in a concentration-dependent manner. Suppression was maximal (50.4%) at 10 microM AjA (Parthritis. Development of nonpsychoactive therapeutically useful synthetic analogs of Cannabis constituents, such as AjA, may help resolve the ongoing debate about the use of marijuana as medicine.

  8. The Protective Role of Carnosic Acid against Beta-Amyloid Toxicity in Rats

    Directory of Open Access Journals (Sweden)

    H. Rasoolijazi


    Full Text Available Oxidative stress is one of the pathological mechanisms responsible for the beta- amyloid cascade associated with Alzheimer’s disease (AD. Previous studies have demonstrated the role of carnosic acid (CA, an effective antioxidant, in combating oxidative stress. A progressive cognitive decline is one of the hallmarks of AD. Thus, we attempted to determine whether the administration of CA protects against memory deficit caused by beta-amyloid toxicity in rats. Beta-amyloid (1–40 was injected by stereotaxic surgery into the Ca1 region of the hippocampus of rats in the Amyloid beta (Aβ groups. CA was delivered intraperitoneally, before and after surgery in animals in the CA groups. Passive avoidance learning and spontaneous alternation behavior were evaluated using the shuttle box and the Y-maze, respectively. The degenerating hippocampal neurons were detected by fluoro-jade b staining. We observed that beta-amyloid (1–40 can induce neurodegeneration in the Ca1 region of the hippocampus by using fluoro-jade b staining. Also, the behavioral tests revealed that CA may recover the passive avoidance learning and spontaneous alternation behavior scores in the Aβ + CA group, in comparison with the Aβ group. We found that CA may ameliorate the spatial and learning memory deficits induced by the toxicity of beta-amyloid in the rat hippocampus.

  9. Multifunctional acid formation from the gas-phase ozonolysis of beta-pinene. (United States)

    Ma, Yan; Marston, George


    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. 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;


    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......, 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...

  11. 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; de Wildeman, Stefaan; Feringa, B.L.; B. Janssen, Dick


    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

  12. CRM 1-mediated degradation and agonist-induced down-regulation of beta-adrenergic receptor mRNAs. (United States)

    Bai, Ying; Lu, Huafei; Machida, Curtis A


    The beta1-adrenergic receptor (beta1-AR) mRNAs are post-transcriptionally regulated at the level of mRNA stability and undergo accelerated agonist-mediated degradation via interaction of its 3' untranslated region (UTR) with RNA binding proteins, including the HuR nuclear protein. In a previous report [Kirigiti et al. (2001). Mol. Pharmacol. 60:1308-1324], we examined the agonist-mediated down-regulation of the rat beta1-AR mRNAs, endogenously expressed in the rat C6 cell line and ectopically expressed in transfectant hamster DDT1MF2 and rat L6 cells. In this report, we determined that isoproterenol treatment of neonatal rat cortical neurons, an important cell type expressing beta1-ARs in the brain, results in significant decreases in beta1-AR mRNA stability, while treatment with leptomycin B, an inhibitor of the nuclear export receptor CRM 1, results in significant increases in beta1-AR mRNA stability and nuclear retention. UV-crosslinking/immunoprecipitation and glycerol gradient fractionation analyses indicate that the beta1-AR 3' UTR recognize complexes composed of HuR and multiple proteins, including CRM 1. Cell-permeable peptides containing the leucine-rich nuclear export signal (NES) were used as inhibitors of CRM 1-mediated nuclear export. When DDT1MF2 transfectants were treated with isoproterenol and peptide inhibitors, only the co-addition of the NES inhibitor reversed the isoproterenol-induced reduction of beta1-AR mRNA levels. Our results suggest that CRM 1-dependent NES-mediated mechanisms influence the degradation and agonist-mediated down-regulation of the beta1-AR mRNAs.

  13. 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


    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.

  14. 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.


    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.

  15. Estrogenic pyrethroid pesticides regulate expression of estrogen receptor transcripts in mouse Sertoli cells differently from 17beta-estradiol. (United States)

    Taylor, J S; Thomson, B M; Lang, C N; Sin, F Y T; Podivinsky, E


    Studies suggested that exposure to agricultural pesticides may affect male fertility. Pyrethroids are widely used pesticides due to their insecticidal potency and low mammalian toxicity. A recombinant yeast assay system incorporating the human alpha-estrogen receptor was used to analyze the estrogenicity of a range of readily available pyrethroid pesticides. The commercial product Ripcord Plus showed estrogenic activity by this assay. To determine whether pyrethroid compounds might exert an effect on male fertility, mouse Sertoli cells were exposed in vitro to the endogenous estrogen, 17beta-estradiol, and selected estrogenic pyrethroids. Following exposure, transcript levels of the alpha- and beta-estrogen receptors were assessed. Exposure of Sertoli cells to the pyrethroid compounds, both at high and at low published serum concentrations, affected the expression of the two estrogen receptors; however, the influence on estrogen receptor gene expression was different from the effect from exposure to 17beta-estradiol. These results from our model systems suggest that (1) estrogenic pyrethroid pesticides affect the estrogen receptors, and therefore potentially the endocrine system, in a different manner from that of endogenous estrogen, and (2) should cells in the male testes be exposed to pyrethroid pesticides, male fertility may be affected through molecular mechanisms involving estrogen receptors.

  16. Antidepressant-like effect of 17beta-estradiol: involvement of dopaminergic, serotonergic, and (or) sigma-1 receptor systems. (United States)

    Dhir, Ashish; Kulkarni, S K


    17beta-estradiol has been reported to possess antidepressant-like activity in animal models of depression, although the mechanism for its effect is not well understood. The present study is an effort in this direction to explore the mechanism of the antidepressant-like effect of 17beta-estradiol in a mouse model(s) of behavioral depression (despair behavior). Despair behavior, expressed as helplessness to escape from a situation (immobility period), as in a forced swim test in which the animals are forced to swim for a total of 6 min, was recorded. The antiimmobility effects (antidepressant-like) of 17beta-estradiol were compared with those of standard drugs like venlafaxine (16 mg/kg, i.p.). 17beta-estradiol produced a U-shaped effect in decreasing the immobility period. It had no effect on locomotor activity of the animal. The antidepressant-like effect was comparable to that of venlafaxine (16 mg/kg, i.p.). 17beta-estradiol also exhibited a similar profile of antidepressant action in the tail suspension test. When coadministered with other antidepressant drugs, 17beta-estradiol (5 microg/kg, i.p.) potentiated the antiimmobility effect of subeffective doses of fluoxetine (5 mg/kg, i.p.), venlafaxine (2 mg/kg, i.p.), or bupropion (10 mg/kg, i.p.), but not of desipramine (5 mg/kg, i.p.) or tranylcypromine (2 mg/kg, i.p.), in the forced swim test. The reduction in the immobility period elicited by 17beta-estradiol (20 microg/kg, i.p.) was reversed by haloperidol (0.5 mg/kg, i.p.; a D(2) dopamine receptor antagonist), SCH 23390 (0.5 mg/kg, i.p.; a D(1) dopamine receptor antagonist), and sulpiride (5 mg/kg, i.p.; a specific dopamine D(2) receptor antagonist). In mice pretreated with (+)-pentazocine (2.5 mg/kg, i.p.; a high-affinity sigma-1 receptor agonist), 17beta-estradiol (5 microg/kg, i.p.) produced a synergistic effect. In contrast, pretreatment with progesterone (10 mg/kg, s.c.; a sigma-1 receptor antagonist neurosteroid), rimcazole (5 mg/kg, i.p.; another sigma

  17. Genes, Gender, Environment, and Novel Functions of Estrogen Receptor Beta in the Susceptibility to Neurodevelopmental Disorders

    Directory of Open Access Journals (Sweden)

    Mukesh Varshney


    Full Text Available Many neurological disorders affect men and women differently regarding prevalence, progression, and severity. It is clear that many of these disorders may originate from defective signaling during fetal or perinatal brain development, which may affect males and females differently. Such sex-specific differences may originate from chromosomal or sex-hormone specific effects. This short review will focus on the estrogen receptor beta (ERβ signaling during perinatal brain development and put it in the context of sex-specific differences in neurodevelopmental disorders. We will discuss ERβ’s recent discovery in directing DNA de-methylation to specific sites, of which one such site may bear consequences for the susceptibility to the neurological reading disorder dyslexia. We will also discuss how dysregulations in sex-hormone signaling, like those evoked by endocrine disruptive chemicals, may affect this and other neurodevelopmental disorders in a sex-specific manner through ERβ.

  18. Genes, Gender, Environment, and Novel Functions of Estrogen Receptor Beta in the Susceptibility to Neurodevelopmental Disorders (United States)

    Varshney, Mukesh; Nalvarte, Ivan


    Many neurological disorders affect men and women differently regarding prevalence, progression, and severity. It is clear that many of these disorders may originate from defective signaling during fetal or perinatal brain development, which may affect males and females differently. Such sex-specific differences may originate from chromosomal or sex-hormone specific effects. This short review will focus on the estrogen receptor beta (ERβ) signaling during perinatal brain development and put it in the context of sex-specific differences in neurodevelopmental disorders. We will discuss ERβ’s recent discovery in directing DNA de-methylation to specific sites, of which one such site may bear consequences for the susceptibility to the neurological reading disorder dyslexia. We will also discuss how dysregulations in sex-hormone signaling, like those evoked by endocrine disruptive chemicals, may affect this and other neurodevelopmental disorders in a sex-specific manner through ERβ. PMID:28241485

  19. Synthesis of the sup 11 C-labelled. beta. -adrenergic receptor ligands atenolol, metoprolol and propanolol

    Energy Technology Data Exchange (ETDEWEB)

    Antoni, G.; Ulin, J.; Laangstroem, B. (Uppsala Univ. (Sweden). Dept. of Organic Chemistry)


    The {sup 11}C-labelled {beta}-adrenergic receptor ligands atenolol 1, metoprolol 2 and propranolol 3 have been synthesized by an N-alkylation reaction using (2-{sup 11}C)isopropyl iodide. The labelled isopropyl iodide was prepared in a one-pot reactor system from ({sup 11}C)carbon dioxide and obtained in 40% radiochemical yield within 14 min reaction time. The total reaction times for compounds 1-3, counted from the start of the isopropyl iodide synthesis and including purification were 45-55 min. The products were obtained in 5-15% radiochemical yields and with radiochemical purities higher than 98%. The specific activity ranged from 0.4 to 4 GBq/{mu}mol. In a typical experiment starting with 4 GBq around 75 MBq of product was obtained. (author).

  20. 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: [INCT Energia e Ambiente, Universidade Federal do Rio de Janeiro, RJ (Brazil)


    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)

  1. Oestrogen receptor-alpha and -beta expression in breast implant capsules: experimental findings and clinical correlates. (United States)

    Persichetti, Paolo; Segreto, Francesco; Carotti, Simone; Marangi, Giovanni Francesco; Tosi, Daniele; Morini, Sergio


    Myofibroblasts provide a force to decrease the surface area of breast implant capsules as the collagen matrix matures. 17-β-Oestradiol promotes myofibroblast differentiation and contraction. The aim of the study was to investigate the expression of oestrogen receptors α and β in capsular tissue. The study enrolled 70 women (80 capsules) who underwent expander or implant removal, following breast reconstruction. Specimens were stained with haematoxylin/eosin, Masson trichrome and immunohistochemistry and immunofluorescence stainings for alpha-smooth muscle actin (α-SMA), oestrogen receptor-alpha (ER-α) and oestrogen receptor-beta (ER-β). The relationship between anti-oestrogenic therapy and capsular severity was evaluated. A retrospective analysis of 233 cases of breast reconstruction was conducted. Myofibroblasts expressed ER-α, ER-β or both. In the whole sample, α-SMA score positively correlated with ER-α (p = 0.022) and ER-β expression (p < 0.004). ER-β expression negatively correlated with capsular thickness (p < 0.019). In capsules surrounding expanders α-SMA and ER-α, expressions negatively correlated with time from implantation (p = 0.002 and p = 0.016, respectively). The incidence of grade III-IV contracture was higher in patients who did not have anti-oestrogenic therapy (p < 0.036); retrospective analysis of 233 cases confirmed this finding (p < 0.0001). This study demonstrates the expression of oestrogen receptors in myofibroblasts of capsular tissue. A lower contracture severity was found in patients who underwent anti-oestrogenic therapy.

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

    Directory of Open Access Journals (Sweden)

    Bu Lihong


    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.

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

  4. In vivo occupancy of female rat brain estrogen receptors by 17beta-estradiol and tamoxifen. (United States)

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


    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.

  5. Vertebral Artery Aneurysm Mimicking as Left Subclavian Artery Aneurysm in a Patient with Transforming Growth Factor Beta Receptor II Mutation. (United States)

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


    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.

  6. Effect of fenoterol-induced constitutive beta(2)-adrenoceptor activity on contractile receptor function in airway smooth muscle

    NARCIS (Netherlands)

    de Vries, B; Roffel, AF; Zaagsma, J; Meurs, H


    In the present study, we investigated the effect of fenoterol-induced constitutive beta (2)-adrenoceptor activity on muscarinic receptor agonist- and histamine-induced bovine tracheal smooth muscle contractions. Bovine tracheal smooth muscle strips were incubated with 10 muM fenoterol or vehicle for

  7. 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


    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


    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...

  9. In pursuit of alpha4beta2 nicotinic receptor partial agonists for smoking cessation: carbon analogs of (-)-cytisine. (United States)

    Coe, Jotham W; Vetelino, Michael G; Bashore, Crystal G; Wirtz, Michael C; Brooks, Paige R; Arnold, Eric P; Lebel, Lorraine A; Fox, Carol B; Sands, Steven B; Davis, Thomas I; Schulz, David W; Rollema, Hans; Tingley, F David; O'Neill, Brian T


    The preparation and biological activity of analogs of (-)-cytisine, an alpha4beta2 nicotinic receptor partial agonist, are discussed. All-carbon-containing phenyl ring replacements of the pyridone ring system, generated via Heck cyclization protocols, exhibited weaker affinity and lower efficacy partial agonist profiles relative to (-)-cytisine. In vivo, selected compounds exhibit lower efficacy partial agonist profiles than that of (-)-cytisine.

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

    NARCIS (Netherlands)

    Schmidt, Martina; Michel, Martin C.


    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

  11. 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 B; Sørensen, Per Soelberg;


    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....

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

    DEFF Research Database (Denmark)

    Sørensen, Torben Lykke; Sellebjerg, F


    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...

  13. Sequential mutations in the interleukin-3 (IL3)/granulocyte-macrophage colony-stimulating factor/IL5 receptor beta-subunit genes are necessary for the complete conversion to growth autonomy mediated by a truncated beta C subunit. (United States)

    Hannemann, J; Hara, T; Kawai, M; Miyajima, A; Ostertag, W; Stocking, C


    An amino-terminally truncated beta C receptor (beta C-R) subunit of the interleukin-3 (IL3)/granulocyte-macrophage colony-stimulating factor/IL5 receptor complex mediates factor-independent and tumorigenic growth in two spontaneous mutants of a promyelocytic cell line. The constitutive activation of the JAK2 protein kinase in these mutants confirms that signaling occurs through the truncated receptor protein. Noteworthily, in addition to a 10-kb deletion in the beta C-R subunit gene encoding the truncated receptor, several secondary and independent mutations that result in the deletion or functional inactivation of the allelic beta C-R subunit and the closely related beta IL3-R subunit genes were observed in both mutants, suggesting that such mutations are necessary for the full oncogenic penetrance of the truncated beta C-R subunit. Reversion of these mutations by the expression of the wild-type beta C-R in the two mutants resulted in a fivefold decrease in cloning efficiency of the mutants in the absence of IL3, confirming a functional interaction between the wild-type and truncated proteins. Furthermore, expression of the truncated beta C-R subunit in factor-dependent myeloid cells did not immediately render the cells autonomous but increased the spontaneous frequency to factor-independent growth by 4 orders of magnitude. Implications for both leukemogenic progression and receptor-subunit interaction and signaling are discussed.

  14. 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;


    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...

  15. Alveolar macrophages stimulated with titanium dioxide, chrysotile asbestos, and residual oil fly ash upregulate the PDGF receptor-alpha on lung fibroblasts through an IL-1beta-dependent mechanism. (United States)

    Lindroos, P M; Coin, P G; Badgett, A; Morgan, D L; Bonner, J C


    Enhanced proliferation of fibroblasts is a primary characteristic of lung fibrosis. Macrophage-secreted platelet-derived growth factor (PDGF) is a potent mitogen and chemoattractant for lung fibroblasts. The magnitude of the fibroblast PDGF response is dependent on the number of PDGF receptor alpha (PDGF-R alpha) relative to PDGF-R beta at the cell surface. We recently reported that upregulation of the PDGF-R alpha subtype by interleukin (IL)-1beta results in enhanced lung fibroblast proliferation in response to PDGF-AA, PDGF-AB, and PDGF-BB whereas transforming growth factor (TGF)-beta1 has the opposite effect. Both IL-1beta and TGF-beta1 are produced by particle-activated macrophages in vivo and in vitro. We studied the net effect of macrophage conditioned medium (MOCM), which contains both IL-1beta and TGF-beta1, on the expression of the lung fibroblast PDGF receptor system. MOCM obtained from unstimulated, titanium dioxide (TiO2)-, chrysotile asbestos-, or residual oil fly ash (ROFA)-exposed macrophages in vitro increased [125I]PDGF-AA binding 3-, 6-, 6-, and 20-fold, respectively. These increases correlated with increased PDGF-R alpha mRNA and protein expression as shown by northern and western assays. PDGF-AB and -BB-stimulated [3H]thymidine incorporation by fibroblasts was enhanced 5-, 5-, 10-, and 20-fold by pretreatment with MOCM from unstimulated, TiO2-, asbestos-, and ROFA-exposed macrophages, respectively. [125I]PDGF-AA binding experiments using the IL-1 receptor antagonist blocked the upregulatory effect of all MOCM samples. Latent TGF-beta1 present in MOCM was activated by acid treatment, inhibiting upregulation by approximately 60%, a result similar to experiments with IL-1beta and TGF-beta1 mixtures. Treatment with a TGF-beta neutralizing antibody restored full upregulatory activity to acidified MOCM. Thus activated macrophages increase lung fibroblast PDGF-R alpha primarily due to the secretion of IL-1beta. Intratracheal instillation of ROFA

  16. Stringent V beta requirement for the development of NK1.1+ T cell receptor-alpha/beta+ cells in mouse liver. (United States)

    Ohteki, T; MacDonald, H R


    The liver of C57BL/6 mice contains a major subset of CD4+8- and CD4-8- T cell receptor (TCR)-alpha/beta+ cells expressing the polymorphic natural killer NK1.1 surface marker. Liver NK1.1+TCR-alpha/beta+ (NK1+ T) cells require interaction with beta2-microglobulin-associated, major histocompatibility complex I-like molecules on hematopoietic cells for their development and have a TCR repertoire that is highly skewed to Vbeta8.2, Vbeta7, and Vbeta2. We show here that congenic C57BL/6.Vbeta(a) mice, which lack Vbeta8- expressing T cells owing to a genomic deletion at the Vbeta locus, maintain normal levels of liver NK1+ T cells owing to a dramatic increase in the proportion of cells expressing Vbeta7 and Vbeta2 (but not other Vbetas). Moreover, in C57BL/6 congenic TCR-V Vbeta3 and -Vbeta8.1 transgenic mice (which in theory should not express other Vbeta, owing to allelic exclusion at the TCR-beta locus), endogenous TCR-Vbeta8.2, Vbeta7, and Vbeta2 (but not other Vbetas) are frequently expressed on liver NK1+T cells but absent on lymph node T cells. Finally, when endogenous V beta expression is prevented in TCR-Vbeta3 and Vbeta8.1 transgenic mice (by introduction of a null allele at the C beta locus), the development of liver NK1+T cells is totally abrogated. Collectively, our data indicate that liver NK1+T cells have a stringent requirement for expression of TCR-Vbeta8.2, Vbeta7, or Vbeta2 for their development.

  17. 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.

  18. QSAR study of selective ligands for the thyroid hormone receptor beta. (United States)

    Liu, Huanxiang; Gramatica, Paola


    In this paper, an accurate and reliable QSAR model of 87 selective ligands for the thyroid hormone receptor beta 1 (TRbeta1) was developed, based on theoretical molecular descriptors to predict the binding affinity of compounds with receptor. The structural characteristics of compounds were described wholly by a large amount of molecular structural descriptors calculated by DRAGON. Six most relevant structural descriptors to the studied activity were selected as the inputs of QSAR model by a robust optimization algorithm Genetic Algorithm. The built model was fully assessed by various validation methods, including internal and external validation, Y-randomization test, chemical applicability domain, and all the validations indicate that the QSAR model we proposed is robust and satisfactory. Thus, the built QSAR model can be used to fast and accurately predict the binding affinity of compounds (in the defined applicability domain) to TRbeta1. At the same time, the model proposed could also identify and provide some insight into what structural features are related to the biological activity of these compounds and provide some instruction for further designing the new selective ligands for TRbeta1 with high activity.

  19. Estrogenic effect of the MEK1 inhibitor PD98059 on endogenous estrogen receptor alpha and beta. (United States)

    Cotrim, Cândida Z; Amado, Francisco L; Helguero, Luisa A


    Estrogens are key regulators in mammary development and breast cancer and their effects are mediated by estrogen receptors alpha (ERα) and beta (ERβ). These two receptors are ligand activated transcription factors that bind to regulatory regions in the DNA known as estrogen responsive elements (EREs). ERα and ERβ activation is subject to modulation by phosphorylation and p42/p44 MAP kinases are the best characterized ER modifying kinases. Using a reporter gene (3X-ERE-TATA-luciferase) to measure activation of endogenous ERs, we found that MEK1 inhibitor PD98059, used in concentrations insufficient to inhibit MEK1 activation of p42/p44 MAP kinases, exerted estrogenic effects on the reporter gene and on the ERE-regulated RIP 140 protein. Such estrogenic effects were observed in mammary epithelial HC11 cells and occur on unliganded ERα and ligand activated ERβ. Additionally, concentrations of PD98059 able to inhibit p42/p44 phosphorylation were not estrogenic. Further, inhibition of p42 MAP kinase expression with siRNAs also resulted in loss of PD98059 estrogenic effect. In summary, PD98059 in concentrations below the inhibitory for MEK1, exerts estrogenic effects in HC11 mammary epithelial cells.

  20. Bile acid receptors and nonalcoholic fatty liver disease

    Institute of Scientific and Technical Information of China (English)


    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.

  1. High affinity retinoic acid receptor antagonists: analogs of AGN 193109. (United States)

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


    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.

  2. 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


    in response to glucagon and glucose, the glucose excursion resulting from both a glucagon challenge and intraperitoneal glucose tolerance test (IPGTT) was significantly reduced in RIP-Gcgr mice compared with controls. However, RIP-Gcgr mice display similar glucose responses to an insulin challenge. beta...... in vivo, we generated mice overexpressing the Gcgr specifically on pancreatic beta-cells (RIP-Gcgr). In vivo and in vitro insulin secretion in response to glucagon and glucose was increased 1.7- to 3.9-fold in RIP-Gcgr mice compared with controls. Consistent with the observed increase in insulin release...... and impaired glucose tolerance (IGT) were reduced in RIP-Gcgr mice compared with controls. Furthermore, the insulin response of RIP-Gcgr mice to an IPGTT was twice that of controls when fed the HFD. These data indicate that increased pancreatic beta-cell expression of the Gcgr increased insulin secretion...

  3. 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)


    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.

  4. Evaporation of a model skin lotion with beta-hydroxy acids. (United States)

    Al Bawab, A; Friberg, S E; Fusco, C


    Two beta-hydroxy acids, malic and salicylic acids were combined with a non-ionic surfactant, a commercial pentaoxyethylene sorbitan mono-oleate and water to form a simple model of a skin lotion and the phase diagrams were determined. One emulsion formulation with relative amounts of the three components similar to those in commercial lotions was used to observe microscopically the changes in the emulsion structure during evaporation. The microscope images were subsequently compared to the information from the phase diagram under equilibrium conditions. The results showed the behavior of the systems of the two acids to be distinctly different; as exemplified by that of a typical formulation with 3% by weight of acid and 5% of surfactant. The malic acid system consisted of vesicles, exclusively formed by the surfactant and water, in an aqueous molecular solution of the acid and the initial evaporation resulted in an increase of the acid concentration in the aqueous solution to reach 35.5%, before solid crystals of the acid solid solution appeared. The salicylic acid formulation, on the other hand, already at the beginning of the determination consisted of water, particles of the acid solid solution and surfactant vesicles. In both cases the remaining deposit after total evaporation was particles of a solid acid solution and liquid surfactant.

  5. Generation of an estrogen receptor beta-iCre knock-in mouse. (United States)

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


    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.

  6. Immunolocalization of alpha-keratins and associated beta-proteins in lizard epidermis shows that acidic keratins mix with basic keratin-associated beta-proteins. (United States)

    Alibardi, Lorenzo


    The differentiation of the corneous layers of lizard epidermis has been analyzed by ultrastructural immunocytochemistry using specific antibodies against alpha-keratins and keratin associated beta-proteins (KAbetaPs, formerly indicated as beta-keratins). Both beta-cells and alpha-cells of the corneous layer derive from the same germinal layer. An acidic type I alpha-keratin is present in basal and suprabasal layers, early differentiating clear, oberhautchen, and beta-cells. Type I keratin apparently disappears in differentiated beta- and alpha-layers of the mature corneous layers. Conversely, a basic type II alpha-keratin rich in glycine is absent or very scarce in basal and suprabasal layers and this keratin likely does not pair with type I keratin to form intermediate filaments but is weakly detected in the pre-corneous and corneous alpha-layer. Single and double labeling experiments show that in differentiating beta-cells, basic KAbetaPs are added and replace type-I keratin to form the hard beta-layer. Epidermal alpha-keratins contain scarce cysteine (0.2-1.4 %) that instead represents 4-19 % of amino acids present in KAbetaPs. Possible chemical bonds formed between alpha-keratins and KAbetaPs may derive from electrostatic interactions in addition to cross-linking through disulphide bonds. Both the high content in glycine of keratins and KAbetaPs may also contribute to increase the hydrophobicy of the beta- and alpha-layers and the resistance of the corneous layer. The increase of gly-rich KAbetaPs amount and the bonds to the framework of alpha-keratins give rise to the inflexible beta-layer while the cys-rich KAbetaPs produce a pliable alpha-layer.

  7. Ascorbic acid Beta-Carotene and Amino acids in Capsicum (Capsicum annuum during fruit development in Himalayan Hills

    Directory of Open Access Journals (Sweden)

    P. C. Pant


    Full Text Available Capsicum varieties viz HC-201 & HC-202 developed at ARU, Almora took 35 days from fruit set to ripening. Results showed significant positive correlation for ascorbic acid and Beta-carotene with days to maturity. Out of eight ninhydrin positive products, only seven could be identified viz, hydroxyproline, proline, lysine, 5-alanine, arginine, threonine and methionine, at the later stages of the fruit development. All amino acids except methionine were found either absent or in traces at the earlier stages of fruit development.

  8. Rapid yeast estrogen bioassays stably expressing human estrogen receptors alpha and beta, and green fluorescent protein: a comparison of different compounds with both receptor types. (United States)

    Bovee, Toine F H; Helsdingen, Richard J R; Rietjens, Ivonne M C M; Keijer, Jaap; Hoogenboom, Ron L A P


    Previously, we described the construction of a rapid yeast bioassay stably expressing human estrogen receptor (hERalpha) and yeast enhanced green fluorescent protein (yEGFP) in response to estrogens. In the present study, the properties of this assay were further studied by testing a series of estrogenic compounds. Furthermore, a similar assay was developed based on the stable expression of human estrogen receptor beta (hERbeta). When exposed to 17beta-estradiol, the maximum transcriptional activity of the ERbeta cytosensor was only about 40% of the activity observed with ERalpha, but the concentration where half-maximal activation is reached (EC50), was about five times lower. The relative estrogenic potencies (REP), defined as the ratio between the EC50 of 17beta-estradiol and the EC50 of the compound, of the synthetic hormones dienestrol, hexestrol and especially mestranol were higher with ER, while DES was slightly more potent with ERbeta. The gestagens progesterone and medroxyprogesterone-acetate showed no response, whereas the androgen testosterone showed a very weak response. The anabolic agent, 19-nortestosterone showed a clear dose-related response with estrogen receptor but not beta. The phytoestrogens coumestrol, genistein, genistin, daidzein, daidzin and naringenin were relatively more potent with ERbeta. Ranking of the estrogenic potency with ER was: 17beta-estradiol > 8-prenylnaringenin > coumestrol > zearalenone > genistein > genistin > naringenin. The ranking with the ERbeta was: 17beta-estradiol > coumestrol > genistein > zearalenone > 8-prenylnaringen > daidzein > naringenin > genistin > daidzin. The hop estrogen 8-prenylnaringenin is relatively more potent with ERalpha. These data show that the newly developed bioassays are valuable tools for the rapid and high-throughput screening for estrogenic activity.

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

    Directory of Open Access Journals (Sweden)

    Francisco José Sánchez Castellanos


    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.

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

    NARCIS (Netherlands)

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


    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

  11. Rapid agonist-induced loss of sup 125 I-. beta. -endorphin opioid receptor sites in NG108-15, but not SK-N-SH neuroblastoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Cone, R.I.; Lameh, J.; Sadee, W. (Univ. of California, San Francisco (United States))


    The authors have measured {mu} and {delta} opioid receptor sites on intact SK-N-SH and NG108-15 neuroblastoma cells, respectively, in culture. Use of {sup 125}I-{beta}-endorphin ({beta}E) as a tracer, together with {beta}E(6-31) to block high-affinity non-opioid binding in both cell lines, permitted the measurement of cell surface {mu} and {delta} opioid receptor sites. Labeling was at {delta} sites in NG108-15 cells and predominantly at {mu} sites in SK-N-SH cells. Pretreatment with the {mu} and {delta} agonist, DADLE, caused a rapid loss of cell surface {delta} receptor sites in NG108-15 cells, but failed to reduce significantly {mu} receptor density in SK-N-SH cells.

  12. 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. (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


    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.

  13. Bile acid nuclear receptor FXR and digestive system diseases

    Directory of Open Access Journals (Sweden)

    Lili Ding


    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.

  14. Selective agonists of retinoic acid receptors: comparative toxicokinetics and embryonic exposure. (United States)

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


    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.

  15. Distinct Phosphorylation Clusters Determine the Signaling Outcome of Free Fatty Acid Receptor 4/G Protein-Coupled Receptor 120

    DEFF Research Database (Denmark)

    Prihandoko, Rudi; Alvarez-Curto, Elisa; Hudson, Brian D;


    It is established that long-chain free fatty acids includingω-3 fatty acids mediate an array of biologic responses through members of the free fatty acid (FFA) receptor family, which includes FFA4. However, the signaling mechanisms and modes of regulation of this receptor class remain unclear. He...

  16. PDGF-BB-mediated activation of p42(MAPK) is independent of PDGF beta-receptor tyrosine phosphorylation. (United States)

    Cartel, N J; Liu, J; Wang, J; Post, M


    Herein, we investigated the activity of mitogen-activated protein kinase (MAPK), a key component of downstream signaling events, which is activated subsequent to platelet-derived growth factor (PDGF)-BB stimulation. Specifically, p42(MAPK) activity peaked 60 min after addition of PDGF-BB, declined thereafter, and was determined not to be a direct or necessary component of glycosaminoglycan (GAG) synthesis. PDGF-BB also activated MAPK kinase 2 (MAPKK2) but had no effect on MAPKK1 and Raf-1 activity. Chemical inhibition of Janus kinase, phosphatidylinositol 3-kinase, Src kinase, or tyrosine phosphorylation inhibition of the PDGF beta-receptor (PDGFR-beta) did not abrogate PDGF-BB-induced p42(MAPK) activation or its threonine or tyrosine phosphorylation. A dominant negative cytoplasmic receptor for hyaluronan-mediated motility variant 4 (RHAMMv4), a regulator of MAPKK-MAPK interaction and activation, did not inhibit PDGF-BB-induced p42(MAPK) activation nor did a construct expressing PDGFR-beta with cytoplasmic tyrosines mutated to phenylalanine. However, overexpression of a dominant negative PDGFR-beta lacking the cytoplasmic signaling domain abrogated p42(MAPK) activity. These results suggest that PDGF-BB-mediated activation of p42(MAPK) requires the PDGFR-beta but is independent of its tyrosine phosphorylation.

  17. Molecular analysis of T-cell receptor beta genes in cutaneous T-cell lymphoma reveals Jbeta1 bias. (United States)

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


    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.

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

    DEFF Research Database (Denmark)

    Wellendorph, Petrine; Bräuner-Osborne, Hans


    -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. [Ecogenetic aspects of the study of phenotypes and levels of beta-aminoisobutyric acid excretion]. (United States)

    Spitsyn, V A; Afanas'eva, I S; Alekseeva, N V


    The levels of excretion of beta-aminoisobutyric acid (BAIB) in urea were examined in five groups. The distribution of BAIB concentration revealed the existence of high and low excretors in each group. Asbestosis patients had the lowest frequency of high excretors. The BAIB concentration among high excretors was similar for all the groups. The BAIB levels of low excretors varied. The most alike were two children groups, asbestosis patients and the workers from the town Asbest.

  20. 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))


    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.

  1. Live Borrelia burgdorferi preferentially activate interleukin-1 beta gene expression and protein synthesis over the interleukin-1 receptor antagonist. (United States)

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


    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

  2. Soman- or kainic acid-induced convulsions decrease muscarinic receptors but not benzodiazepine receptors

    Energy Technology Data Exchange (ETDEWEB)

    Churchill, L.; Pazdernik, T.L.; Cross, R.S.; Nelson, S.R.; Samson, F.E. (Univ. of Kansas Medical Center, Kansas City (USA))

    (3H)Quinuclidinyl benzilate (QNB) binding to muscarinic receptors decreased in the rat forebrain after convulsions induced by a single dose of either soman, a potent inhibitor of acetylcholinesterase, or kainic acid, an excitotoxin. A Rosenthal plot revealed that the receptors decreased in number rather than affinity. When the soman-induced convulsions were blocked, the decrease in muscarinic receptors at 3 days was less extensive than when convulsions occurred and at 10 days they approached control levels in most of the brain areas. The most prominent decrements in QNB binding were in the piriform cortex where the decline in QNB binding is probably related to the extensive convulsion-associated neuropathology. The decrements in QNB binding after convulsions suggest that the convulsive state leads to a down-regulation of muscarinic receptors in some brain areas. In contrast to the decrease in QNB binding after convulsions, (3H)flunitrazepam binding to benzodiazepine receptors did not change even in the piriform cortex where the loss in muscarinic receptors was most prominent. Thus, it appears that those neuronal processes that bear muscarinic receptors are more vulnerable to convulsion-induced change than those with benzodiazepine receptors.

  3. Partially deglycosylated equine LH preferentially activates beta-arrestin-dependent signaling at the follicle-stimulating hormone receptor. (United States)

    Wehbi, Vanessa; Tranchant, Thibaud; Durand, Guillaume; Musnier, Astrid; Decourtye, Jérémy; Piketty, Vincent; Butnev, Vladimir Y; Bousfield, George R; Crépieux, Pascale; Maurel, Marie-Christine; Reiter, Eric


    Deglycosylated FSH is known to trigger poor Galphas coupling while efficiently binding its receptor. In the present study, we tested the possibility that a deglycosylated equine LH (eLHdg) might be able to selectively activate beta-arrestin-dependent signaling. We compared native eLH to an eLH derivative [i.e. truncated eLHbeta (Delta121-149) combined with asparagine56-deglycosylated eLHalpha (eLHdg)] previously reported as an antagonist of cAMP accumulation at the FSH receptor (FSH-R). We confirmed that, when used in conjunction with FSH, eLHdg acted as an antagonist for cAMP accumulation in HEK-293 cells stably expressing the FSH-R. Furthermore, when used alone at concentrations up to 1 nM, eLHdg had no detectable agonistic activity on cAMP accumulation, protein kinase A activity or cAMP-responsive element-dependent transcriptional activity. At higher concentrations, however, a weak agonistic action was observed with eLHdg, whereas eLH led to robust responses whatever the concentration. Both eLH and eLHdg triggered receptor internalization and led to beta-arrestin recruitment. Both eLH and eLHdg triggered ERK and ribosomal protein (rp) S6 phosphorylation at 1 nM. The depletion of endogenous beta-arrestins had only a partial effect on eLH-induced ERK and rpS6 phosphorylation. In contrast, ERK and rpS6 phosphorylation was completely abolished at all time points in beta-arrestin-depleted cells. Together, these results show that eLHdg has the ability to preferentially activate beta-arrestin-dependent signaling at the FSH-R. This finding provides a new conceptual and experimental framework to revisit the physiological meaning of gonadotropin structural heterogeneity. Importantly, it also opens a field of possibilities for the development of selective modulators of gonadotropin receptors.

  4. Characteristics of gamma-aminobutyric acid (GABA receptors in the rat central nervous system.

    Directory of Open Access Journals (Sweden)



    Full Text Available Characteristics of gamma-aminobutyric acid (GABA were investigated in the rat central nervous system by radioreceptor assay (RRA. Scatchard analysis revealed that the rat brain had two distinct GABA binding sites with an apparent dissociation constant (Kd of 11.7 nM and 34.7 nM. The highest level of specific [3H]-GABA binding was found in the rat cerebellum. Imidazole acetic acid, a potent GABA agonist, was effective in displacing [3H]-GABA binding but beta-alanine was slightly effective in inhibiting [3H]-GABA binding. Muscimol, the most potent GABA agonist, has been used as a ligand to characterize the postsynaptic GABA receptors. However, the maximal binding capacity (Bmax of muscimol-RRA was about 3 times larger than that of GABA-RRA, suggesting that muscimol might label not only GABA receptors but other unknown receptors as well. An endogenous inhibitor of GABA receptor binding was purified from the P2 fraction of rat brain with 0.05% Triton X-100. The endogenous inhibitor was competitive with GABA on GABA binding sites. The inhibition by the endogenous inhibitor of GABA receptor binding was blocked by the allosteric effect of diazepam. In the presence of diazepam, [3H]-GABA binding with the endogenous inhibitor was larger than that with GABA, whereas there was no difference in the absence of diazepam. This indicated that the endogenous inhibitor was not GABA itself. The molecular weight of the endogenous inhibitor was estimate by gel filtration to be less than 3,000 daltons.

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

    Directory of Open Access Journals (Sweden)

    John A Findlay


    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.

  6. BACE1 activity impairs neuronal glucose oxidation: rescue by beta-hydroxybutyrate and lipoic acid. (United States)

    Findlay, John A; Hamilton, David L; Ashford, Michael L J


    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. Regulation of topoisomerase II alpha and beta in HIV-1 infected and uninfected neuroblastoma and astrocytoma cells: involvement of distinct nordihydroguaretic acid sensitive inflammatory pathways. (United States)

    Mandraju, Raj Kumar; Kondapi, Anand K


    The activity of Topoisomerase II alpha and beta isoforms is tightly regulated during different phases of cell cycle. In the present study, the action of anti-inflammatory agents, nordihydroguaretic acid (NDGA) is analyzed in HIV-1 infected CXCR4(+), CCR5(+) and CD4(-) SK-N-SH neuroblastoma, CXCR4(+), CCR5(+) and CD4(-) 1321N1 astrocytoma and CXCR4(+), CCR5(+/-) and CD4(-) GO-G-CCM glioblastoma cell lines. In SK-N-SH and 1321N1 the expression of Topoisomerase II alpha is concomitant with that of LOX-5 and is highly sensitive to NDGA, while the Topoisomerase II beta is expressed along with TNFalpha and exhibits low sensitivity to NDGA, suggesting distinct pathways of regulation for the two isoforms. HIV-1 infection in these cells enhanced the expression of Topo II alpha and beta. Further, the regulation of Topo II beta and TNFalpha in infected and uninfected SK cells is distinctly different. HIV-1 gp120 derived peptides could block HIV-1 mediated inflammation and Topoisomerase II alpha and beta expression, suggesting the viral mediated response. A combination of NDGA, gp-120 derived peptides and AZT has completely blocked the viral replication, suggesting the enhancement of potency of AZT under the suppression of inflammatory response. In contrast, the expression of Topo II alpha and beta was stimulated by NDGA in GO-G-CCM cells showing distinct regulatory pathway in these cells that was resistant to HIV-1 infection. This suggests the requirement of inflammatory response for productive viral infection. In summary, an induction of co-receptor mediated inflammatory response can distinctly enhance regulated expression of the cellular Topo II alpha and beta and promote productive infection in neurons and astrocytes.

  8. 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


    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...

  9. Expression of transient receptor potential ankyrin 1 (TRPA1 and its role in insulin release from rat pancreatic beta cells.

    Directory of Open Access Journals (Sweden)

    De-Shou Cao

    Full Text Available OBJECTIVE: Several transient receptor potential (TRP channels are expressed in pancreatic beta cells and have been proposed to be involved in insulin secretion. However, the endogenous ligands for these channels are far from clear. Here, we demonstrate the expression of the transient receptor potential ankyrin 1 (TRPA1 ion channel in the pancreatic beta cells and its role in insulin release. TRPA1 is an attractive candidate for inducing insulin release because it is calcium permeable and is activated by molecules that are produced during oxidative glycolysis. METHODS: Immunohistochemistry, RT-PCR, and Western blot techniques were used to determine the expression of TRPA1 channel. Ca²⁺ fluorescence imaging and electrophysiology (voltage- and current-clamp techniques were used to study the channel properties. TRPA1-mediated insulin release was determined using ELISA. RESULTS: TRPA1 is abundantly expressed in a rat pancreatic beta cell line and freshly isolated rat pancreatic beta cells, but not in pancreatic alpha cells. Activation of TRPA1 by allyl isothiocyanate (AITC, hydrogen peroxide (H₂O₂, 4-hydroxynonenal (4-HNE, and cyclopentenone prostaglandins (PGJ₂ and a novel agonist methylglyoxal (MG induces membrane current, depolarization, and Ca²⁺ influx leading to generation of action potentials in a pancreatic beta cell line and primary cultured pancreatic beta cells. Activation of TRPA1 by agonists stimulates insulin release in pancreatic beta cells that can be inhibited by TRPA1 antagonists such as HC030031 or AP-18 and by RNA interference. TRPA1-mediated insulin release is also observed in conditions of voltage-gated Na⁺ and Ca²⁺ channel blockade as well as ATP sensitive potassium (K(ATP channel activation. CONCLUSIONS: We propose that endogenous and exogenous ligands of TRPA1 cause Ca²⁺ influx and induce basal insulin release and that TRPA1-mediated depolarization acts synergistically with K(ATP channel blockade to

  10. Structure of the inclusion complex of beta-cyclodextrin with 1,12-dodecanedioic acid using synchrotron radiation data; a detailed dimeric beta-cyclodextrin structure (United States)

    Makedonopoulou; Mavridis


    A detailed crystal structure study of the dimeric inclusion complex of beta-cyclodextrin (betaCD) with 1,12-dodecanedioic acid is presented [IUPAC name: beta-cyclodextrin-1,12-dodecanedioic acid (2/1)]. The structure was solved with synchrotron high-resolution data (0.65 A) at 100 K [crystal data: P1, Z= 1, a = 18.153 (7), b = 15.456 (8), c = 15.251 (4) A, alpha = 102.81 (2), beta = 113.13 (2), gamma = 99.90 (3)degrees, V = 3,673 (3) A3, R = 0.0474 for 25,134 unique reflections with I > 2sigma(I)]. Moreover, the room-temperature structure is used for comparison [crystal data: P1, Z = 1, a = 18.220 (3), b = 15.488 (3), c = 15.409 (3) A, alpha = 102.903 (6), beta = 113.122 (5), gamma = 99.708 (5)degrees, V = 3735.2 (12) A3, R = 0.0828 for 8,235 unique reflections with I > 2sigma(I)]. Combining the high-resolution data and the low-temperature made possible the location of the disordered guest molecule, 1,12-dodecanedioic acid, inside the wide cavity of the macrocycle formed by two betaCD monomers. Moreover, almost all the H atoms of the betaCD macrocycle and many of the water molecules have been located in the low-temperature structure. Thus, for the first time, it has been possible to show in detail, up to now only given by neutron diffraction data, that two betaCD monomers self-assemble through O3...O3 intermolecular hydrogen bonds to form the betaCD dimer, as well as describe the hydrogen-bonding scheme between the dimer's hydroxyl groups among themselves and with water molecules in the lattice. The long guest threads through two host molecules forming a [3]pseudorotaxane. Its polar carboxyl groups, fully hydrated at the primary faces of the betaCD dimers, influence their packing so that those faces are exposed to the solvent. This is in contrast to the packing of the beta-cyclodextrin complexes of the corresponding aliphatic monoacids, where the dimeric complexes form channels in order to isolate the terminal methyl group from the water environment of the lattice.

  11. Raman study of the formation of beta silicomolybdic acid supported on silica, prepared by impregnation method (United States)

    Phuc, Nguyen Huu Huy; Ohkita, Hironobu; Mizushima, Takanori; Kakuta, Noriyoshi


    Beta silicomolibdic acid/silica (β-SMA, a metastable form of silicomolybdic acid - H4SiMo12O40) forms by the impregnation of fumed silica into molybdenum solution obtained by hydrolyzation of MoO2Cl2. β-SMA/silica is found to be stable up to 300 °C after calcination for 1 h due to the existence of an interlayer MoO3 between silica surface and β-SMA. Structures of molybdenum species in the preparation process (including precursor solution) were analyzed by Raman spectroscopy and XRD.

  12. Influence of TGF-beta1 on the expression of BSP, DSP, TGF-beta1 receptor I and Smad proteins during reparative dentinogenesis. (United States)

    Hwang, Yun-Chan; Hwang, In-Nam; Oh, Won-Mann; Park, Joo-Cheol; Lee, Dong-Seol; Son, Ho-Hyun


    Reparative dentin has a wide variety of manifestations ranging from a regular, tubular form to an irregular, atubular form. However, the characteristics of reparative dentin have not been clarified. This study hypothesized that the level of bone sialoprotein (BSP) expression will increase if the newly formed reparative dentin is bone-like but the dentin sialophosphoprotein (DSPP) level will decrease. In order to test this hypothesis, the expression of BSP and DSP was examined by immunohistochemistry and the expression of BSP was measured by in situ hybridization in an animal model. The pulps of 12 maxillary right first molars from twelve male rats were exposed and capped with MTA. In addition, in order to understand the role of transforming growth factor-beta 1 (TGF-beta1) during reparative dentinogenesis, the expression of BSP and DSPP mRNA was analyzed by RT-PCR in a human dental pulp cell culture, and the transforming growth factor-beta 1 receptors (TbetaRI) and Smad 2/3 were examined by immunofluorescence in an animal model. DSP was expressed in the normal odontoblasts and odontoblast-like cells of the reparative dentin. Interestingly, BSP was strongly expressed in the odontoblast-like cells of reparative dentin. The level of the TbetaRI and Smad 2/3 proteins was higher in the reparative dentin than in the normal dentin. TGF-beta1 up-regulated BSP in the human pulp cell cultures. This suggests that reparative dentin has both dentinogenic and osteogenic characteristics that are mediated by TGF-beta1.

  13. Selective Orthosteric Free Fatty Acid Receptor 2 (FFA2) Agonists (United States)

    Schmidt, Johannes; Smith, Nicola J.; Christiansen, Elisabeth; Tikhonova, Irina G.; Grundmann, Manuel; Hudson, Brian D.; Ward, Richard J.; Drewke, Christel; Milligan, Graeme; Kostenis, Evi; Ulven, Trond


    Free fatty acid receptor 2 (FFA2; GPR43) is a G protein-coupled seven-transmembrane receptor for short-chain fatty acids (SCFAs) that is implicated in inflammatory and metabolic disorders. The SCFA propionate has close to optimal ligand efficiency for FFA2 and can hence be considered as highly potent given its size. Propionate, however, does not discriminate between FFA2 and the closely related receptor FFA3 (GPR41). To identify FFA2-selective ligands and understand the molecular basis for FFA2 selectivity, a targeted library of small carboxylic acids was examined using holistic, label-free dynamic mass redistribution technology for primary screening and the receptor-proximal G protein [35S]guanosine 5′-(3-O-thio)triphosphate activation, inositol phosphate, and cAMP accumulation assays for hit confirmation. Structure-activity relationship analysis allowed formulation of a general rule to predict selectivity for small carboxylic acids at the orthosteric binding site where ligands with substituted sp3-hybridized α-carbons preferentially activate FFA3, whereas ligands with sp2- or sp-hybridized α-carbons prefer FFA2. The orthosteric binding mode was verified by site-directed mutagenesis: replacement of orthosteric site arginine residues by alanine in FFA2 prevented ligand binding, and molecular modeling predicted the detailed mode of binding. Based on this, selective mutation of three residues to their non-conserved counterparts in FFA3 was sufficient to transfer FFA3 selectivity to FFA2. Thus, selective activation of FFA2 via the orthosteric site is achievable with rather small ligands, a finding with significant implications for the rational design of therapeutic compounds selectively targeting the SCFA receptors. PMID:21220428

  14. Hydroxylated analogues of 5-aminovaleric acid as 4-aminobutyric acidB receptor antagonists

    DEFF Research Database (Denmark)

    Kristiansen, U; Hedegaard, A; Herdeis, C;


    The (R) and (S) forms of 5-amino-2-hydroxyvaleric acid (2-OH-DAVA) and 5-amino-4-hydroxyvaleric acid (4-OH-DAVA) were designed as structural hybrids of the 4-aminobutyric acidB (GABAB) agonist (R)-(-)-4-amino-3-hydroxybutyric acid [(R)-(-)-3-OH-GABA] and the GABAB antagonist 5-aminovaleric acid....... All four compounds were weak inhibitors of GABAA receptor binding in rat brain, and none of them significantly affected synaptosomal GABA uptake. Based on molecular modeling studies it has been demonstrated that low-energy conformations of (R)-(-)-3-OH-GABA, (S)-(-)-2-OH-DAVA, and (R)-(-)-4-OH...

  15. Factors associated with estrogen receptors-alpha (ER-alpha) and -beta (ER-beta) and progesterone receptor abundance in obese and non obese pre- and post-menopausal women. (United States)

    Meza-Muñoz, Dalia Edith; Fajardo, Martha E; Pérez-Luque, Elva Leticia; Malacara, Juan Manuel


    There is scarce information about the factors associated with estrogen receptors (ER) at menopause. In 113 volunteers pre- and post-menopausal healthy women, grouped as with and without obesity, estrogen receptors-alpha and -beta, and progesterone receptor (PR) were measured by immunohistochemistry in skin punch biopsies obtained from the external gluteal area. In pre-menopausal women, biopsies and a blood sample were performed between days 7 and 14 of the cycle. Serum hormone levels were measured by immunoradiometric assay or radioimmunoassay. After menopause, ER and PR amounts decreased significantly. At pre-menopause, obese women had lower PR levels than non obese (P<.006). In the post-menopausal group, obese women showed higher ER-alpha (P<.03) and ER-beta (P<.02) levels than the non obese group. In the analysis of factors associated with the amount of steroid receptors for the total group, log[ER-alpha], log[ER-beta], and log[PR] were associated with age (P<.002, <.005, and <.004, respectively). The log[ER-alpha] was also associated with log[FSH] (P<.0008); meanwhile, the log[PR] showed a marginal correlation with log[FSH]. In pre-menopausal women no factor associated with any of the three receptors was found. In post-menopausal women log[ER-alpha] was associated with log[estrone] and log[DHEAS] (P<.003 and <.02, respectively). log[PR] was associated with BMI (P<.002), years since menopause (P<.05), and log[DHEAS] (P<.003). We concluded that ER and PR diminish sharply at post-menopause. At this stage the amount of receptors depends on several factors such as BMI, years since menopause, and androgen precursors.

  16. A role for estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ) in collagen biosynthesis in mouse skin (United States)

    Markiewicz, Margaret; Znoyko, Sergey; Stawski, Lukasz; Ghatnekar, Angela; Gilkeson, Gary; Trojanowska, Maria


    Hormonal regulation of the dermal collagenous extracellular matrix plays a key role in maintaining proper tissue homeostasis, however the factors and pathways involved in this process are not fully defined. This study investigated the role of estrogen receptors (ERs) in the regulation of collagen biosynthesis in mice lacking ERα or ERβ. Collagen content was significantly increased in the skin of ΕRα-/- mice as measured by acetic acid extraction and the hydroxyproline assay and correlated with the decreased levels of MMP-15 and elevated collagen production by ΕRα-/- fibroblasts. In contrast, collagen content was decreased in the skin of ERβ-/- mice despite markedly increased collagen production by ERβ-/- fibroblasts. However, expression of several matrix metalloproteinases (MMPs), including MMP-8 and -15 was significantly elevated suggesting increased degradation of dermal collagen. Furthermore, ERβ-/- mice were characterized by significantly reduced levels of small leucine proteoglycans (SLRPs), lumican and decorin, leading to the defects in collagen fibrillogenesis and possibly less stable collagen fibrils. ERα-/- mice also exhibited fibrils with irregular structure and size, which correlated with increased levels of lumican and decorin. Together, these results demonstrate distinct functions of estrogen receptors in the regulation of collagen biosynthesis in mouse skin in vivo. PMID:22895361

  17. Design, synthesis, and evaluation of 2 beta-alkenyl penam sulfone acids as inhibitors of beta-lactamases. (United States)

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


    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.

  18. Effect of clavulanic acid on activity of beta-lactam antibiotics in Serratia marcescens isolates producing both a TEM beta-lactamase and a chromosomal cephalosporinase. (United States)

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


    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

  19. 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: [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)


    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

  20. Complement receptor 1 is a sialic acid-independent erythrocyte receptor of Plasmodium falciparum.

    Directory of Open Access Journals (Sweden)

    Carmenza Spadafora

    Full Text Available Plasmodium falciparum is a highly lethal malaria parasite of humans. A major portion of its life cycle is dedicated to invading and multiplying inside erythrocytes. The molecular mechanisms of erythrocyte invasion are incompletely understood. P. falciparum depends heavily on sialic acid present on glycophorins to invade erythrocytes. However, a significant proportion of laboratory and field isolates are also able to invade erythrocytes in a sialic acid-independent manner. The identity of the erythrocyte sialic acid-independent receptor has been a mystery for decades. We report here that the complement receptor 1 (CR1 is a sialic acid-independent receptor for the invasion of erythrocytes by P. falciparum. We show that soluble CR1 (sCR1 as well as polyclonal and monoclonal antibodies against CR1 inhibit sialic acid-independent invasion in a variety of laboratory strains and wild isolates, and that merozoites interact directly with CR1 on the erythrocyte surface and with sCR1-coated microspheres. Also, the invasion of neuraminidase-treated erythrocytes correlates with the level of CR1 expression. Finally, both sialic acid-independent and dependent strains invade CR1 transgenic mouse erythrocytes preferentially over wild-type erythrocytes but invasion by the latter is more sensitive to neuraminidase. These results suggest that both sialic acid-dependent and independent strains interact with CR1 in the normal red cell during the invasion process. However, only sialic acid-independent strains can do so without the presence of glycophorin sialic acid. Our results close a longstanding and important gap in the understanding of the mechanism of erythrocyte invasion by P. falciparum that will eventually make possible the development of an effective blood stage vaccine.

  1. Increased mandibular condylar growth in mice with estrogen receptor beta deficiency. (United States)

    Kamiya, Yosuke; Chen, Jing; Xu, Manshan; Utreja, Achint; Choi, Thomas; Drissi, Hicham; Wadhwa, Sunil


    Temporomandibular joint (TMJ) disorders predominantly afflict women of childbearing age, suggesting a role for female hormones in the disease process. In long bones, estrogen acting via estrogen receptor beta (ERβ) inhibits axial skeletal growth in female mice. However, the role of ERβ in the mandibular condyle is largely unknown. We hypothesize that female ERβ-deficient mice will have increased mandibular condylar growth compared to wild-type (WT) female mice. This study examined female 7-day-old, 49-day-old, and 120-day-old WT and ERβ knockout (KO) mice. There was a significant increase in mandibular condylar cartilage thickness as a result of an increased number of cells, in the 49-day-old and 120-day-old female ERβ KO compared with WT controls. Analysis in 49-day-old female ERβ KO mice revealed a significant increase in collagen type X, parathyroid hormone-related protein (Pthrp), and osteoprotegerin gene expression and a significant decrease in receptor activator for nuclear factor κ B ligand (Rankl) and Indian hedgehog (Ihh) gene expression, compared with WT controls. Subchondral bone analysis revealed a significant increase in total condylar volume and a decrease in the number of osteoclasts in the 49-day-old ERβ KO compared with WT female mice. There was no difference in cell proliferation in condylar cartilage between the genotypes. However, there were differences in the expression of proteins that regulate the cell cycle; we found a decrease in the expression of Tieg1 and p57 in the mandibular condylar cartilage from ERβ KO mice compared with WT mice. Taken together, our results suggest that ERβ deficiency increases condylar growth in female mice by inhibiting the turnover of fibrocartilage.

  2. Increased levels of beta 2-microglobulin, soluble interleukin-2 receptor, and soluble CD8 in patients with subacute sclerosing panencephalitis. (United States)

    Mehta, P D; Kulczycki, J; Mehta, S P; Sobczyk, W; Coyle, P K; Sersen, E A; Wisniewski, H M


    We measured beta 2-microglobulin (beta 2-M), soluble interleukin-2 receptor (sIL-2R), and soluble CD8 (sCD8) antigen levels in paired cerebrospinal fluid (CSF) and sera from patients with subacute sclerosing panencephalitis (SSPE), multiple sclerosis (MS), and other neurological diseases (OND) using enzyme-linked immunosorbent assay. beta 2-M was significantly increased in CSF of the SSPE group compared to the MS or the OND group. Similarly, beta 2-M in the MS versus OND group was significantly increased in CSF. Although serum levels of beta 2-M were similar in the three groups, the CSF/serum ratios were higher in SSPE versus the MS group and in the MS versus the OND group. Levels of sIL-2R and sCD8 were higher in SSPE CSF than OND CSF; however, there were no differences between levels in SSPE and MS CSF. The levels of sIL-2R were increased in SSPE sera compared to those of MS or the OND group, whereas levels of sCD8 in serum from the three groups were similar. The findings of increased CSF/serum ratio of beta 2-M and higher levels of serum sIL-2R and CSF sCD8 in SSPE patients are consistent with those seen in patients with acute and chronic viral infections. When the levels between the initial and follow-up CSF and serum samples from SSPE patients were compared, the data showed that CSF levels of sCD8 elevated during periods of clinical worsening and decreased during clinical improvement. In contrast, serum beta 2-M decreased during periods of worsening and increased during improvement. The measurement of serum beta 2-M and CSF sCD8 may be useful in SSPE patients as markers to monitor disease activity.

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


    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

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


    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.

  5. In silico discovery of novel Retinoic Acid Receptor agonist structures

    Directory of Open Access Journals (Sweden)

    Samuels Herbert H


    Full Text Available Abstract Background Several Retinoic Acid Receptors (RAR agonists have therapeutic activity against a variety of cancer types; however, unacceptable toxicity profiles have hindered the development of drugs. RAR agonists presenting novel structural and chemical features could therefore open new avenues for the discovery of leads against breast, lung and prostate cancer or leukemia. Results We have analysed the induced fit of the active site residues upon binding of a known ligand. The derived binding site models were used to dock over 150,000 molecules in silico (or virtually to the structure of the receptor with the Internal Coordinates Mechanics (ICM program. Thirty ligand candidates were tested in vitro. Conclusions Two novel agonists resulting from the predicted receptor model were active at 50 nM. One of them displays novel structural features which may translate into the development of new ligands for cancer therapy.

  6. Water Sparing in Chronic Ethanol Exposure is Associated With Elevated Renal Estrogen Receptor Beta and Vasopressin V2 Receptor mRNA in the Female Rate (United States)


    quality as a thesis for the degree of Master of Science in Medical and Molecular Physiology. THESIS COMMITTEE Chairperson ii TABLE OF CONTENTS List of...of biology = Revista brasleira de biologia 62, 609-614 20. Bevan, D. R. (1978) Osmometry. 1. Terminology and principles of measurement. Anaesthesia 33... molecular endocrinology 24, 145-155 32. Suzuki, S., and Handa, R. J. (2004) Regulation of estrogen receptor-beta expression in the female rat

  7. The cannabinoid beta-caryophyllene (BCP) induces neuritogenesis in PC12 cells by a cannabinoid-receptor-independent mechanism. (United States)

    Santos, Neife Aparecida Guinaim; Martins, Nádia Maria; Sisti, Flávia Malvestio; Fernandes, Laís Silva; Ferreira, Rafaela Scalco; de Freitas, Osvaldo; Santos, Antônio Cardozo


    Beta-caryophyllene (BCP) is a phytocannabinoid whose neuroprotective activity has been mainly associated with selective activation of cannabinoid-type-2 (CB2) receptors, inhibition of microglial activation and decrease of inflammation. Here, we addressed the potential of BCP to induce neuritogenesis in PC12 cells, a model system for primary neuronal cells that express trkA receptors, respond to NGF and do not express CB2 receptors. We demonstrated that BCP increases the survival and activates the NGF-specific receptor trkA in NGF-deprived PC12 cells, without increasing the expression of NGF itself. The neuritogenic effect of BCP in PC12 cells was abolished by k252a, an inhibitor of the NGF-specific receptor trkA. Accordingly, BCP did not induce neuritogenesis in SH-SY5Y neuroblastoma cells, a neuronal model that does not express trkA receptors and do not respond to NGF. Additionally, we demonstrated that BCP increases the expression of axonal-plasticity-associated proteins (GAP-43, synapsin and synaptophysin) in PC12 cells. It is known that these proteins are up-regulated by NGF in neurons and neuron-like cells, such as PC12 cells. Altogether, these findings suggest that BCP activates trka receptors and induces neuritogenesis by a mechanism independent of NGF or cannabinoid receptors. This is the first study to show such effects of BCP and their beneficial role in neurodegenerative processes should be further investigated.

  8. Slow-dissociation effect of common signaling subunit beta c on IL5 and GM-CSF receptor assembly. (United States)

    Ishino, Tetsuya; Harrington, Adrian E; Zaks-Zilberman, Meirav; Scibek, Jeffery J; Chaiken, Irwin


    Receptor activation by IL5 and GM-CSF is a sequential process that depends on their interaction with a cytokine-specific subunit alpha and recruitment of a common signaling subunit beta (betac). In order to elucidate the assembly dynamics of these receptor subunits, we performed kinetic interaction analysis of the cytokine-receptor complex formation by a surface plasmon resonance biosensor. Using the extracellular domains of receptor fused with C-terminal V5-tag, we developed an assay method to co-anchor alpha and betac subunits on the biosensor surface. We demonstrated that dissociation of the cytokine-receptor complexes was slower when both subunits were co-anchored on the biosensor surface than when alpha subunit alone was anchored. The slow-dissociation effect of betac had a similar impact on GM-CSF receptor stabilization to that of IL5. The effects were abolished by alanine replacement of either Tyr18 or Tyr344 residue in betac, which together constitute key parts of a cytokine binding epitope. The data argue that betac plays an important role in preventing the ligand-receptor complexes from rapidly dissociating. This slow-dissociation effect of betac explains how, when multiple betac cytokine receptor alpha subunits are present on the same cell surface, selective betac usage can be controlled by sequestration in stabilized cytokine-alpha-betac complexes.

  9. Developmental expression of estrogen receptor beta in the brain of prairie voles (Microtus ochrogaster). (United States)

    Ploskonka, Stephanie D; Eaton, Jennifer L; Carr, Michael S; Schmidt, Jennifer V; Cushing, Bruce S


    Here, for the first time, the expression of estrogen receptor beta (ERβ) is characterized in the brains of the highly prosocial prairie vole (Microtus ochrogaster). ERβ immunoreactivity was compared in weanlings (postnatal Day 21) and adult males and females. The results indicate several major findings. First, unlike ERα, ERβ expression is not sexually dimorphic. Second, the adult pattern of ERβ-IR is established at the time of weaning, as there were no age-dependent effects on distribution. Finally, ERβ does not appear to be as widely distributed in voles compared with rats and mice. High levels of ERβ-IR were observed in several regions/nuclei within the medial pre-optic area, ventrolateral pre-optic nuclei, and in the hypothalamus, especially in the paraventricular and supraoptic nuclei. The visualization of ERβ in prairie voles is important as the socially monogamous prairie vole functions as a human relevant model system for studying the expression of social behavior and social deficit disorders. Future studies will now be able to determine the effect of treatments on the expression and/or development of ERβ in this highly social species.

  10. Effects of environmental estrogenic chemicals on AP1 mediated transcription with estrogen receptors alpha and beta. (United States)

    Fujimoto, Nariaki; Honda, Hiroaki; Kitamura, Shigeyuki


    There has been much discussion concerning endocrine disrupting chemicals suspected of exerting adverse effects in both wildlife and humans. Since the majority of these compounds are estrogenic, a large number of in vitro tests for estrogenic characteristics have been developed for screening purpose. One reliable and widely used method is the reporter gene assay employing estrogen receptors (ERs) and a reporter gene with a cis-acting estrogen responsive element (ERE). Other elements such as AP1 also mediate estrogenic signals and the manner of response could be quite different from that of ERE. Since this has yet to be explored, the ER mediated AP1 activity in response to a series of environmental estrogens was investigated in comparison with ERE findings. All the compounds exhibited estrogenic properties with ERE-luc and their AP1 responses were quite similar. These was one exception, however, p,p'-DDT (1,1,1,-trichloro-2,2-bis(p-chlorophenyl)ethane) did not exert any AP1-luc activity, while it appeared to be estrogenic at 10(-7) to 10(-5)M with the ERE action. None of the compounds demonstrated ER beta:AP1 activity. These data suggest that significant differences can occur in responses through the two estrogen pathways depending on environmental chemicals.

  11. 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


    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.

  12. 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


    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

  13. Tetrahydro-beta-carboline-3-carboxylic acids and contaminants of L-tryptophan. (United States)

    Adachi, J; Asano, M; Ueno, Y


    Methods for the separation, identification, and quantitative assay of contaminants of L-tryptophan implicated in eosinophilia-myalgia syndrome (EMS) are described. Propylsulfonic acid (PRS), benzenesulfonic acid (SCX), and octyl-derivatized silica (C8) bonded-phase cartridges were used for the separation; LC-MS and GC-MS for identification; and HPLC-UV-fluorescence detection for quantitative analyses of norharman, harman, tetrahydro-beta-carboline-3-carboxylic acid (TCCA), 1-methyltetrahydro-beta-carboline-3-carboxylic acid (MTCA), 1,1'-ethylidenbis(tryptophan) (EBT), and 3-(phenylamino)alanine (PAA). The tissue distribution, excretion, and metabolism of these contaminants of L-tryptophan associated with EMS after acute and chronic dosage regimens are described. Considerable amounts of EBT were observed in the large intestine of rats administered EBT, showing a transfer without decomposition in gastric fluid. In addition, MTCA was detected in the blood and urine as well as the organs of rats treated with EBT, suggesting MTCA as a major metabolite of EBT. PAA accumulated markedly in the brain, among the organs of rats, after both acute and chronic administration of PAA, while MTCA accumulated in the kidneys of rats after chronic dosage of MTCA. Ethanol and/or acetaldehyde-induced formation of MTCA, as well as tryptophan-induced formation of TCCA, occurred endogenously in man and animals.

  14. Altered beta-adrenergic receptor-stimulated cAMP formation in cultured skin fibroblasts from Alzheimer donors. (United States)

    Huang, H M; Gibson, G E


    An alteration in signal transduction systems in Alzheimer's disease would likely be of pathophysiological significance, because these steps are critical to normal brain function. Since dynamic processes are difficult to study in autopsied brain, the current studies utilized cultured skin fibroblasts. The beta-adrenergic-stimulated increase in cAMP was reduced approximately 80% in fibroblasts from Alzheimer's disease compared with age-matched controls. The deficit in Alzheimer fibroblasts in response to various adrenergic agonists paralleled their beta-adrenergic potency, and enhancement of cAMP accumulation by a non-adrenergic agonist, such as prostaglandin E1, was similar in Alzheimer and control fibroblasts. Diminished adenylate cyclase activity did not underlie these abnormalities, since direct stimulation of adenylate cyclase by forskolin elevated cAMP production equally in Alzheimer and control fibroblasts. Cholera toxin equally stimulated cAMP formation in Alzheimer and control fibroblasts. Moreover, cholera toxin partially reduced isoproterenol-induced cAMP deficit in Alzheimer fibroblasts. Pertussis toxin, on the other hand, did not alter the Alzheimer deficits. The results suggest either that the coupling of the GTP-binding protein(s) to the beta-adrenergic receptor is abnormal or that the sensitivity of receptor is altered with Alzheimer's disease. Further, any hypothesis about Alzheimer's disease must explain why a reduced beta-adrenergic-stimulated cAMP formation persists in tissue culture.

  15. Analysis of T cell receptor alpha beta variability in lymphocytes infiltrating melanoma primary tumours and metastatic lesions

    DEFF Research Database (Denmark)

    Schøller, J; thor Straten, P; Jakobsen, Annette Birck;


    The T cell receptor (TCR) alpha beta variable (V) gene family usage of tumour-infiltrating lymphocytes (TIL) in four different primary human malignant melanomas and their corresponding metastatic lesions was characterized using a recently developed method based on the reverse-transcription-couple......The T cell receptor (TCR) alpha beta variable (V) gene family usage of tumour-infiltrating lymphocytes (TIL) in four different primary human malignant melanomas and their corresponding metastatic lesions was characterized using a recently developed method based on the reverse...... usage of the TCR V gene families V alpha 4, V alpha 5, V alpha 22 and V beta 8, whereas the V beta 3 gene family appeared to be expressed together with HLA-A1. Other highly expressed V gene families, apparently not restricted to either HLA-A1 or -A2, were V alpha 1 (expressed in three of four primary...... tumours) and V alpha 21 (expressed in two of four tumours). We found no evidence suggesting any correlations between the haplotypes HLA-A1 and -A2 and preferential V gene family expression in the metastatic lesions, and the only common feature was V alpha 8, which was found to be highly expressed in two...

  16. Gender-Related Survival Differences Associated With Polymorphic Variants of Estrogen Receptor Beta (ERβ) in Patients with Metastatic Colon Cancer


    Press, Oliver A.; Zhang, Wu; Gordon, Michael A.; Yang, Dongyun; Haiman, Christopher A; Azuma, Mizutomo; Iqbal, Syma; Lenz, Heinz-Josef


    Estrogen replacement therapy in women has demonstrated a protective effect in the development of colonic carcinomas. Gender-related differences in the development of colonic carcinomas have also been reported. Estrogen receptor beta (ERβ) is expressed in colon carcinomas and has demonstrated prognostic value in colon cancer patients. This study investigated an ERβ 3’ non-coding polymorphism associated with transcriptional activity to determine clinical outcome in patients with metastatic colo...

  17. The lactate receptor, G-protein-coupled receptor 81/hydroxycarboxylic acid receptor 1

    DEFF Research Database (Denmark)

    Morland, Cecilie; Lauritzen, Knut Huso; Puchades, Maja;


    We have proposed that lactate is a “volume transmitter” in the brain and underpinned this by showing that the lactate receptor, G-protein-coupled receptor 81 (GPR81, also known as HCA1 or HCAR1), which promotes lipid storage in adipocytes, is also active in the mammalian brain. This includes...... anion channels activated by depolarization. In addition to locally produced lactate, lactate produced by exercising muscle as well as exogenous HCAR1 agonists, e.g., from fruits and berries, might activate the receptor on cerebral blood vessels and brain cells....

  18. Structural model for gamma-aminobutyric acid receptor noncompetitive antagonist binding: widely diverse structures fit the same site. (United States)

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


    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.

  19. Effects of estrogen receptor alpha and beta gene deletion on estrogenic induction of progesterone receptors in the locus coeruleus in female mice. (United States)

    Helena, Cleyde; Gustafsson, Jan-Ake; Korach, Kenneth; Pfaff, Donald; Anselmo-Franci, Janete A; Ogawa, Sonoko


    Locus coeruleus (LC) is involved in the LHRH regulation by gonadal steroids. We investigated the expression of progesterone and estrogen receptors (PR; ER) in LC neurons of ERalpha (alphaERKO) or ERbeta (betaERKO) knockout mice, and their wild-type (alphaWT and betaWT). Immunocytochemical studies showed that LC expresses PR and both ERs, although ERbeta was more abundant. Estradiol benzoate (EB) decreased ERalpha-positive cells in WT and betaERKO mice, and progesterone caused a further reduction, whereas none of the steroids influenced ERbeta expression. ERbeta deletion increased ERalpha while ERalpha deletion did not alter ERbeta expression. In both WT mice, EB increased PR expression, which was diminished by progesterone. These steroid effects were also observed in alphaERKO animals but to a lesser extent, suggesting that ERalpha is partially responsible for the estrogenic induction of PR in LC. Steroid effects on PR in betaERKO mice were similar to those in the alphaERKO but to a lesser extent, probably because PR expression was already high in the oil-treated group. This expression seems to be specific of LC neurons, since it was not observed in other areas studied, the preoptic area and ventromedial nucleus of hypothalamus. These findings show that LC in mice expresses alphaER, betaER, and PR, and that a balance between them may be critical for the physiological control of reproductive function.

  20. Estrogen Receptor Beta Displays Cell Cycle-Dependent Expression and Regulates the G1 Phase through a Non-Genomic Mechanism in Prostate Carcinoma Cells

    Directory of Open Access Journals (Sweden)

    Antoni Hurtado


    Full Text Available Background: It is well known that estrogens regulate cell cycle progression, but the specific contributions and mechanisms of action of the estrogen receptor beta (ERβ remain elusive.

  1. Crystallization and Preliminary X-ray analysis of Human Recombinant Acid beta-glucocerebrosidase, a treatment for Gaucher's Disease (United States)

    Roeber, Dana F.; Achari, Aniruddha; Manavalan, Partha; Edmunds, Tim; Scott, David L.; Curreri, Peter A. (Technical Monitor)


    Acid beta-glucocerebrosidase (N-acylsphingosyl - O - beta-D - glucoside:glucohydrolase) is a lysosomal glycoprotein that catalyzes the hydrolysis of the glycolipid glucocerebroside to glucose and ceramide. Inadequate levels of this enzyme underly the pathophysiology of Gaucher's disease. Cerezyme(R) (Genzyme Corporation, Cambridge, MA) is a partially deglycosylated form of recombinant human acid beta-glucocerebrosidase that is commercially available for the treatment of Gaucher patients. Although acid beta-glucocerebrosidase belongs to a large family of glycosidases, relatively little is known regarding its structural biology. We report the crystallization and the initial diffraction analysis of Cerezyme(R). The crystals are C-centered orthorhombic, with unit-cell parameters of a = 285.0 A, b = 110.2 A, and c = 91.7 A. A 99.9 A complete data set has been collected to 2.75 A with an R(sub sym) of 8.8 %.

  2. Crystallization and preliminary X-ray analysis of recombinant human acid beta-glucocerebrosidase, a treatment for Gaucher's disease (United States)

    Roeber, Dana; Achari, Aniruddha; Manavalan, Partha; Edmunds, Tim; Scott, David L.


    Acid beta-glucocerebrosidase (N-acylsphingosyl-1-O-beta-D-glucoside:glucohydrolase) is a lysosomal glycoprotein that catalyzes the hydrolysis of the glycolipid glucocerebroside to glucose and ceramide. Inadequate levels of this enzyme underly the pathophysiology of Gaucher's disease. Cerezyme (Genzyme Corporation, Cambridge, MA, USA) is a partially deglycosylated form of recombinant human acid beta-glucocerebrosidase that is used in the treatment of Gaucher patients. Although acid beta-glucocerebrosidase belongs to a large family of glycosidases, relatively little is known regarding its structural biology. Here, the crystallization and the initial diffraction analysis of Cerezyme are reported. The crystals are C-centered orthorhombic, with unit-cell parameters a = 285.0, b = 110.2, c = 91.7 A. A 99.9% complete data set has been collected to 2.75 A with an R(sym) of 8.8%.

  3. 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


    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....

  4. 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)


    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.

  5. 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.


    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

  6. N-methyl-D-aspartate receptor antagonist MK-801 and radical scavengers protect cholinergic nucleus basalis neurons against beta-amyloid neurotoxicity

    NARCIS (Netherlands)

    Harkany, T; Mulder, J; Sasvari, M; Abraham, [No Value; Konya, C; Zarandi, M; Penke, B; Luiten, PGM; Nyakas, C


    Previous experimental data indicate the involvement of Ca2+-related excitotoxic processes, possibly mediated by N-Methyl-D-Aspartate (NMDA) receptors, in beta-amyloid (beta A) neurotoxicity. On the other hand, other lines of evidence support the view that free radical generation is a critical step i

  7. Effect of isoprenaline on pentagastrin-stimulated gastric acid secretion in dogs with gastric fistula

    DEFF Research Database (Denmark)

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


    The purpose of this study was to elucidate the effect of a beta 1-adrenoceptor agonist on gastric acid secretion in conscious dogs with gastric fistula. Isoprenaline, a beta 1- and beta 2-agonist was used alone and in conjunction with selective blockade of beta 2- and beta 1-receptors. Isoprenaline...

  8. Peroxisome proliferator-activated receptor alpha (PPARalpha) protects against oleate-induced INS-1E beta cell dysfunction by preserving carbohydrate metabolism

    DEFF Research Database (Denmark)

    Frigerio, F; Brun, T; Bartley, C;


    AIMS/HYPOTHESIS: Pancreatic beta cells chronically exposed to fatty acids may lose specific functions and even undergo apoptosis. Generally, lipotoxicity is triggered by saturated fatty acids, whereas unsaturated fatty acids induce lipodysfunction, the latter being characterised by elevated basal...... enzyme pyruvate carboxylase. PPARalpha overproduction increased both beta-oxidation and fatty acid storage in the form of neutral triacylglycerol, revealing overall induction of lipid metabolism. These observations were substantiated by expression levels of associated genes. CONCLUSIONS...

  9. 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.

  10. Monounsaturated fatty acids prevent the deleterious effects of palmitate and high glucose on human pancreatic beta-cell turnover and function


    Maedler, Kathrin; Oberholzer, José; Bucher, Pascal Alain Robert; Spinas, Giatgen A.; Donath, Marc


    Glucotoxicity and lipotoxicity contribute to the impaired beta-cell function observed in type 2 diabetes. Here we examine the effect of saturated and monounsaturated fatty acids at different glucose concentrations on human beta-cell turnover and secretory function. Exposure of cultured human islets to saturated fatty acid and/or to an elevated glucose concentration for 4 days increased beta-cell DNA fragmentation and decreased beta-cell proliferation. In contrast, the monounsaturated palmitol...

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

    Directory of Open Access Journals (Sweden)

    Marjan Saeedi


    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.

  12. Cloning the promoter for transforming growth factor-beta type III receptor. Basal and conditional expression in fetal rat osteoblasts (United States)

    Ji, C.; Chen, Y.; McCarthy, T. L.; Centrella, M.


    Transforming growth factor-beta binds to three high affinity cell surface molecules that directly or indirectly regulate its biological effects. The type III receptor (TRIII) is a proteoglycan that lacks significant intracellular signaling or enzymatic motifs but may facilitate transforming growth factor-beta binding to other receptors, stabilize multimeric receptor complexes, or segregate growth factor from activating receptors. Because various agents or events that regulate osteoblast function rapidly modulate TRIII expression, we cloned the 5' region of the rat TRIII gene to assess possible control elements. DNA fragments from this region directed high reporter gene expression in osteoblasts. Sequencing showed no consensus TATA or CCAAT boxes, whereas several nuclear factors binding sequences within the 3' region of the promoter co-mapped with multiple transcription initiation sites, DNase I footprints, gel mobility shift analysis, or loss of activity by deletion or mutation. An upstream enhancer was evident 5' proximal to nucleotide -979, and a silencer region occurred between nucleotides -2014 and -2194. Glucocorticoid sensitivity mapped between nucleotides -687 and -253, whereas bone morphogenetic protein 2 sensitivity co-mapped within the silencer region. Thus, the TRIII promoter contains cooperative basal elements and dispersed growth factor- and hormone-sensitive regulatory regions that can control TRIII expression by osteoblasts.

  13. Development of novel silicon-containing inverse agonists of retinoic acid receptor-related orphan receptors. (United States)

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


    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.

  14. 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.

  15. 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


    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 hamster...... ovary (CHO) cells. In contrast to the parent compound ibotenic acid, which is a potent group I and II agonist, the (S)-forms of homoibotenic acid and its analogues are selective and potent group I antagonists whereas the (R)-forms are inactive both as agonists and antagonists at group I, II, and III m......Glu receptors. Interestingly, (S)-homoibotenic acid and the analogues display equal potency at both mGlu1alpha and mGlu5a with Ki values in the range of 97 to 490 microM, (S)-homoibotenic acid and (S)-2-amino-3-(4-butyl-3-hydroxyisoxazol-5-yl)propionic acid [(S)-4-butylhomoibotenic acid] displaying the lowest...

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

    Directory of Open Access Journals (Sweden)

    Yu Mi Choi


    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.

  17. Period 1 and estrogen receptor-beta are downregulated in Chinese colon cancers. (United States)

    Wang, Yupeng; Xing, Tonghai; Huang, Li; Song, Guohe; Sun, Xing; Zhong, Lin; Fan, Junwei; Yan, Dongwang; Zhou, Chongzhi; Cui, Feifei; Yu, Fudong; Chen, Jian; Yu, Yang; Li, Chao; Tang, Huamei; Peng, Zhihai; Wang, Xiaoliang


    To investigate whether Period 1 (PER1) and Estrogen receptor-beta (ER2) are associated with occurrence and development of Chinese colorectal cancers. By using RT-quantitative PCR, tissue microarray (TMA) and immunohistochemistry, we detected mRNA levels and protein levels of PER1 and ER2 in the cancerous tissues and paired normal adjacent tissues in patients with colorectal cancer. Survival analyses were performed by the Kaplan-Meier method utilizing log-rank test and univariate and multivariate Cox proportional modeling to measure 5-year disease-free survival (DFS) and overall survival (OS). Real-time PCR showed that, the delta Ct value (tumor tissue vs. normal mucosa) of PER1 or ER2 is 8.51 ± 2.81 vs. 7.34 ± 2.08 or 12.39 ± 2.43 vs. 9.76 ± 1.75, expression of PER1 and ER2 decreased significantly in tumor tissues compared with noncancerous mucosas of patients with or without metastasis (both of P values <0.001). Spearman test revealed that PER1 and ER2 were significantly down-regulated in cancerous tissues (r=0.283; P<0.001) which was also confirmed by immunohistochemistry of specimens from 203 colon cancer patients in a TMA format. The reduction of PER1 was associated with gender and distant metastasis (P=0.037 and P<0.001, respectively) whereas the decline of ER2 was associated with age (P=0.043) by analyzing the clinical data. However, we were not capable of detecting any association between PER1 level or ER2 level and overall survival (OS) or disease free survival (DFS). It is the first observation of correlated reduction of PER1 and ER2 in Chinese colon cancers, and they do play a certain role in colorectal cancer.

  18. 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;


    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....

  19. Receptor for protons: First observations on Acid Sensing Ion Channels. (United States)

    Krishtal, Oleg


    The history of ASICs began in 1980 with unexpected observation. The concept of highly selective Na(+) current gated by specific receptors for protons was not easily accepted. It took 16 years to get these receptor/channels cloned and start a new stage in their investigation. "The receptor for protons" became ASIC comprising under this name a family of receptor/channels ubiquitous for mammalian nervous system, both peripheral and central. The role of ASICs as putative nociceptors was suggested almost immediately after their discovery. This role subsequently was proven in many forms of pain-related phenomena. Many other functions of ASICs have been also found or primed for speculations both in physiology and in disease. Despite the width of field and strength of efforts, numerous basic questions are to be answered before we understand how the local changes in pH in the nervous tissue transform into electric and messenger signaling via ASICs as transducers. This article is part of the Special Issue entitled 'Acid-Sensing Ion Channels in the Nervous System'.

  20. 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.

  1. Further studies on the covalent crosslinking of thyrotropin to its receptor: evidence that both the alpha and beta subunits of thyrotropin are crosslinked to the receptor. (United States)

    McQuade, R; Thomas, C G; Nayfeh, S N


    Highly purified alpha- and beta-subunits of thyrotropin were individually radioiodinated and, subsequently, recombined with their unlabeled complementary subunits. This procedure resulted in the formation of [125I]thyrotropin(TSH) hybrid molecules which were labeled on only one hormone subunit. Characterization of the binding properties of these two hybrid molecules demonstrated that both yielded nonlinear Scatchard plots with Kd and Bmax values similar to those obtained with radioiodinated native TSH and that both were capable of interaction with the high- and low-affinity binding components of the TSH receptor. The recombined [125I]TSH molecules were then crosslinked to the TSH receptor using disuccinimidyl suberate. Following electrophoresis and autoradiography, two labeled TSH-receptor complexes with Mr of 68,000 and 80,000 were observed. These two complexes exhibited hormone specificity and electrophoretic mobility identical to those previously observed using native [125I]TSH. Crosslinking with increasing concentrations of disuccinimidyl suberate suggested that the formation of the 68,000 and 80,000 complexes was sequential with the 68,000 appearing before the 80,000. Furthermore, the two bands were labeled regardless of which TSH subunit of the hybrid TSH was radioiodinated. These data strongly suggest that the 68,000 and 80,000 TSH-receptor complexes are the result of crosslinking to the TSH alpha-beta dimer and not to one subunit in the case of the 68,000 complex and to the TSH alpha-beta dimer in the case of the 80,000 complex, as had been hypothesized previously.

  2. Stereospecific synthesis of threo- and erythro-beta-hydroxyglutamic acid during kutzneride biosynthesis. (United States)

    Strieker, Matthias; Nolan, Elizabeth M; Walsh, Christopher T; Marahiel, Mohamed A


    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.

  3. Investigation on bile acid receptor regulators. Discovery of cholanoic acid derivatives with dual G-protein coupled bile acid receptor 1 (GPBAR1) antagonistic and farnesoid X receptor (FXR) modulatory activity. (United States)

    Sepe, Valentina; Renga, Barbara; Festa, Carmen; Finamore, Claudia; Masullo, Dario; Carino, Adriana; Cipriani, Sabrina; Distrutti, Eleonora; Fiorucci, Stefano; Zampella, Angela


    Bile acids, the end products of cholesterol metabolism, activate multiple mechanisms through the interaction with membrane G-protein coupled receptors including the bile acid receptor GPBAR1 and nuclear receptors such as the bile acid sensor, farnesoid X receptor (FXR). Even if dual FXR/GPBAR1 agonists are largely considered a novel opportunity in the treatment of several liver and metabolic diseases, selective targeting of one of these receptors represents an attractive therapeutic approach for a wide range of disorders in which dual modulation is associated to severe side effects. In the present study we have investigated around the structure of LCA generating a small library of cholane derivatives, endowed with dual FXR agonism/GPBAR1 antagonism. To the best of our knowledge, this is the first report of bile acid derivatives able to antagonize GPBAR1.

  4. Highly efficient coupling of beta-substituted aminoethane sulfonyl azides with thio acids, toward a new chemical ligation reaction. (United States)

    Merkx, Remco; Brouwer, Arwin J; Rijkers, Dirk T S; Liskamp, Rob M J


    [reaction: see text] A highly efficient coupling of protected beta-substituted aminoethane sulfonyl azides with thio acids is reported. In the case of peptide thio acids, this method encompasses a new chemoselective ligation method. Furthermore, the resulting alpha-amino acyl sulfonamides can be alkylated with suitable electrophiles to obtain densely functionalized sulfonamide scaffolds.

  5. The alpha7 nicotinic acetylcholine receptor-selective antagonist, methyllycaconitine, partially protects against beta-amyloid1-42 toxicity in primary neuron-enriched cultures. (United States)

    Martin, Shelley E; de Fiebre, Nancy Ellen C; de Fiebre, Christopher M


    Studies have suggested that the neuroprotective actions of alpha7 nicotinic agonists arise from activation of receptors and not from the extensive desensitization which rapidly follows activation. Here, we report that the alpha7-selective nicotinic antagonist, methyllycaconitine (MLA), protects against beta-amyloid-induced neurotoxicity; whereas the alpha4beta2-selective antagonist, dihydro-beta-erythroidine, does not. These findings suggest that neuroprotective actions of alpha7-acting agents arise from receptor inhibition/desensitization and that alpha7 antagonists may be useful neuroprotective agents.

  6. 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;


    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...

  7. Amino acid sequence requirements at residues 69 and 238 for the SME-1 beta-lactamase to confer resistance to beta-lactam antibiotics. (United States)

    Majiduddin, Fahd K; Palzkill, Timothy


    Carbapenem antibiotics have been used to counteract resistant strains of bacteria harboring beta-lactamases and extended-spectrum beta-lactamases. Four enzymes from the class A group of beta-lactamases, NMC-A, IMI-1, SME-1, and KPC-1, efficiently hydrolyze carbapenem antibiotics. Sequence comparisons and structural information indicate that cysteines at amino acid residues 69 and 238, which are conserved in all four of these enzymes, form a disulfide bond that is unique to these beta-lactamases. To test whether this disulfide bond is required for catalytic activity, the codons for residues Cys69 and Cys238 were randomized individually and simultaneously by PCR-based mutagenesis to create random replacement libraries for these positions. Mutants that were able to confer resistance to ampicillin, imipenem, or cefotaxime were selected from these libraries. The results indicate that positions Cys69 and Cys238 are critical for hydrolysis of all of the antibiotics tested, suggesting that the disulfide bond is generally required for this enzyme to catalyze the hydrolysis of beta-lactam antibiotics.

  8. 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


    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...

  9. Lipoprotein receptor-related protein-1 mediates amyloid-beta-mediated cell death of cerebrovascular cells.

    NARCIS (Netherlands)

    Wilhelmus, M.M.; Otte-Holler, I.; Triel, J.J. van; Veerhuis, R.; Maat-Schieman, M.L.; Bu, G.; Waal, R.M.W. de; Verbeek, M.M.


    Inefficient clearance of A beta, caused by impaired blood-brain barrier crossing into the circulation, seems to be a major cause of A beta accumulation in the brain of late-onset Alzheimer's disease patients and hereditary cerebral hemorrhage with amyloidosis Dutch type. We observed association of r

  10. Function of the integrin alpha 6 beta 1 in metastatic breast carcinoma cells assessed by expression of a dominant-negative receptor

    DEFF Research Database (Denmark)

    Shaw, L M; Chao, C; Wewer, U M;


    The involvement of the alpha 6 beta a integrin, a laminin receptor, in breast carcinoma progression needs to be addressed rigorously. We report that a human breast carcinoma cell line, MDA-MB-435, known to be highly invasive and metastatic, expresses three potential integrin laminin receptors...... function that involved expression of a cytoplasmic domain deletion mutant of the beta 4 integrin subunit by cDNA transfection. Stable transfectants of MDA-MB-435 cells that expressed this mutant beta 4 subunit were inhibited dramatically in their ability to adhere and migrate on laminin matrices......, and their capacity to invade Matrigel was reduced significantly. These findings support the hypothesis that alpha 6 beta 1 is important for breast cancer progression. Moreover, this approach is a powerful method that should be useful in assessing the role of alpha 6 beta 1 in other cells....

  11. 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.

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

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


    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

  13. Adenosine A2A receptors and uric acid mediate protective effects of inosine against TNBS-induced colitis in rats. (United States)

    Rahimian, Reza; Fakhfouri, Gohar; Daneshmand, Ali; Mohammadi, Hamed; Bahremand, Arash; Rasouli, Mohammad Reza; Mousavizadeh, Kazem; Dehpour, Ahmad Reza


    Inflammatory bowel disease comprises chronic recurrent inflammation of gastrointestinal tract. This study was conducted to investigate inosine, a potent immunomodulator, in 2,4,6-trinitrobenzene sulphonic acid (TNBS)-induced chronic model of experimental colitis, and contribution of adenosine A(2A) receptors and the metabolite uric acid as possible underlying mechanisms. Experimental colitis was rendered in rats by a single colonic administration of 10 mg of TNBS. Inosine, potassium oxonate (a hepatic uricase inhibitor), SCH-442416 (a selective adenosine A(2A) receptor antagonist), inosine+potassium oxonate, or inosine+SCH-442416 were given twice daily for 7 successive days. At the end of experiment, macroscopic and histopathologic scores, colonic malondialdehyde (MDA), Tumor Necrosis Factor-alpha (TNF-α) and Interleukin-1beta (IL-1β) levels, and myeloperoxidase (MPO) activity were assessed. Plasma uric acid level was measured throughout the experiment. Both macroscopic and histological features of colonic injury were markedly ameliorated by either inosine, oxonate or inosine+oxonate. Likewise, the elevated amounts of MPO and MDA abated as well as those of TNF-α and IL-1β (Pacid levels were significantly higher in inosine or oxonate groups compared to control. Inosine+oxonate resulted in an even more elvelated uric acid level than each treatment alone (Pacid and adenosine A(2A) receptors contribute to these salutary properties.

  14. Effect of clavulanic acid on the activities of ten beta-lactam agents against members of the Bacteroides fragilis group. (United States)

    Lamothe, F; Auger, F; Lacroix, J M


    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

  15. 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.


    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

  16. Interleukin (IL)1beta, IL-1alpha, and IL-1 receptor antagonist gene polymorphisms in patients with temporal lobe epilepsy. (United States)

    Kanemoto, K; Kawasaki, J; Miyamoto, T; Obayashi, H; Nishimura, M


    Proinflammatory cytokines, including interleukin (IL)-1beta, are known to modulate effects of neurotoxic neurotransmitters discharged during excitation or inflammation in the central nervous system (CNS). They also regulate development of glial scars at sites of CNS injury. To elucidate a genetic predisposition of temporal lobe epilepsy with hippocampal sclerosis (TLE-HS+), we studied polymorphisms in the IL-1beta, IL-1alpha, and IL-1 receptor antagonist (IL-1RA) genes in 50 patients with TLE-HS+ and in 112 controls. Fifty-three patients who had TLE without HS were also examined (TLE-HS-) as disease controls. The distribution of the biallelic polymorphism in the promoter region at position -511 of the IL-1beta gene (IL-1B-511) was significantly different both between TLE-HS+ patients and controls and between TLE-HS+ and TLE-HS- patients. The differences were due to overrepresentation of the homozygotes for IL-1B-511*2, which is suggested to be a high producer of IL-1beta, in TLE-HS+ patients compared with both controls and TLE-HS- patients. In contrast, there was no difference between TLE-HS- patients and controls. Our data suggest that, in the homozygotes for IL-IB-511*2, minor events in development such as febrile convulsions could set up a cascade leading to HS.

  17. Surface proteome analysis identifies platelet derived growth factor receptor-alpha as a critical mediator of transforming growth factor-beta-induced collagen secretion. (United States)

    Heinzelmann, Katharina; Noskovičová, Nina; Merl-Pham, Juliane; Preissler, Gerhard; Winter, Hauke; Lindner, Michael; Hatz, Rudolf; Hauck, Stefanie M; Behr, Jürgen; Eickelberg, Oliver


    Fibroblasts are extracellular matrix-producing cells in the lung. Fibroblast activation by transforming growth factor-beta leads to myofibroblast-differentiation and increased extracellular matrix deposition, a hallmark of pulmonary fibrosis. While fibroblast function with respect to migration, invasion, and extracellular matrix deposition has been well-explored, little is known about the surface proteome of lung fibroblasts in general and its specific response to fibrogenic growth factors, in particular transforming growth factor-beta. We thus performed a cell-surface proteome analysis of primary human lung fibroblasts in presence/absence of transforming growth factor-beta, followed by characterization of our findings using FACS analysis, Western blot, and siRNA-mediated knockdown experiments. We identified 213 surface proteins significantly regulated by transforming growth factor-beta, platelet derived growth factor receptor-alpha being one of the top down-regulated proteins. Transforming growth factor beta-induced downregulation of platelet derived growth factor receptor-alpha induced upregulation of platelet derived growth factor receptor-beta expression and phosphorylation of Akt, a downstream target of platelet derived growth factor signaling. Importantly, collagen type V expression and secretion was strongly increased after forced knockdown of platelet derived growth factor receptor-alpha, an effect that was potentiated by transforming growth factor-beta. We therefore show previously underappreciated cross-talk of transforming growth factor-beta and platelet derived growth factor signaling in human lung fibroblasts, resulting in increased extracellular matrix deposition in a platelet derived growth factor receptor-alpha dependent manner. These findings are of particular importance for the treatment of lung fibrosis patients with high pulmonary transforming growth factor-beta activity.

  18. Steroidal affinity labels of the estrogen receptor. 3. Estradiol 11 beta-n-alkyl derivatives bearing a terminal electrophilic group: antiestrogenic and cytotoxic properties. (United States)

    Lobaccaro, C; Pons, J F; Duchesne, M J; Auzou, G; Pons, M; Nique, F; Teutsch, G; Borgna, J L


    With the aim of developing a new series of steroidal affinity labels of the estrogen receptor, six electrophilic 11 beta-ethyl (C2), 11 beta-butyl (C4), or 11 beta-decyl (C10) derivatives of estradiol bearing an 11 beta-terminal electrophilic functionality, i.e. bromine (C4), (methylsulfonyl)oxy (C2 and C4), bromoacetamido (C2 and C4), and (p-tolylsulfonyl)oxy (C10), were synthesized. The range of their affinity constants for binding the estrogen receptor was 0.4-37% that of estradiol; the order of increasing affinity (i) relative to the 11 beta-alkyl arm was ethyl compounds, if any, was under 10%. This was in sharp contrast to results obtained using 11 beta-((tosyloxy)decyl)estradiol which labeled from 60% to 90% of the receptor hormone-binding sites with an EC50 of approximately 10 nM. Estrogenic and antiestrogenic activities of the compounds were determined using the MVLN cell line, which was established from the estrogen-responsive mammary tumor MCF-7 cells by stable transfection of a recombinant estrogen-responsive luciferase gene. The two 11 beta-ethyl compounds were mainly estrogenic, whereas the three 11 beta-butyl and the 11 beta-decyl compounds essentially showed antiestrogenic activity. The fact that the chemical reactivities of 11 beta-ethyl and 11 beta-butyl compounds were not compromised by interaction with the estrogen receptor made the synthesized high-affinity compounds potential cytotoxic agents which might be able to exert either (i) a specific action on estrogen-regulated genes or (ii) a more general action in estrogen-target cells. Therefore the ability of the compounds (1) to irreversibly abolish estrogen-dependent expression of the luciferase gene and (2) to affect the proliferation of MVLN cells were determined. All electrophiles were able to irreversibly suppress expression of the luciferase gene; the antiestrogenic electrophiles were more potent than the estrogenic ones but less efficient than 4-hydroxytamoxifen, a classical and chemically

  19. Effect of clavulanic acid on susceptibility of Campylobacter jejuni and Campylobacter coli to eight beta-lactam antibiotics. (United States)

    Gaudreau, C L; Lariviere, L A; Lauzer, J C; Turgeon, F F


    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

  20. Effect of clavulanic acid on susceptibility of Campylobacter jejuni and Campylobacter coli to eight beta-lactam antibiotics.


    Gaudreau, C L; Lariviere, L A; Lauzer, J C; Turgeon, F F


    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.

  1. Concomitant action of structural elements and receptor phosphorylation determines arrestin-3 interaction with the free fatty acid receptor FFA4

    DEFF Research Database (Denmark)

    Butcher, Adrian J; Hudson, Brian D; Shimpukade, Bharat;


    In addition to being nutrients, free fatty acids act as signaling molecules by activating a family of G protein-coupled receptors. Among these is FFA4, previously called GPR120, which responds to medium and long chain fatty acids, including health-promoting ω-3 fatty acids, which have been implic...

  2. 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:; 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)


    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

  3. 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. (United States)

    Van Dam, A M; Malinowsky, D; Lenczowski, M J; Bartfai, T; Tilders, F J


    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.

  4. Modeling the interactions of a peptide-major histocompatibility class I ligand with its receptors. I. Recognition by two alpha beta T cell receptors

    DEFF Research Database (Denmark)

    Rognan, D; Stryhn, A; Fugger, L


    dynamics. Next, three-dimensional models of two different T cell receptors (TCRs) both specific for the Ha255-262/Kk complex were generated based on previously published TCR X-ray structures. Finally, guided by the recently published X-ray structures of ternary TCR/peptide/MHC-I complexes, the TCR models...... the models. They were found to account well for the experimentally obtained data, lending considerable support to the proposed models and suggesting a universal docking mode for alpha beta TCRs to MHC-peptide complexes. Such models may also be useful in guiding future rational experimentation....

  5. 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. (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


    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

  6. Obesity Suppresses Estrogen Receptor Beta Expression in Breast Cancer Cells via a HER2-Mediated Pathway.

    Directory of Open Access Journals (Sweden)

    Laura W Bowers

    Full Text Available Obesity is associated with a worse breast cancer prognosis, while greater breast tumor estrogen receptor beta (ERβ expression is correlated with improved therapy response and survival. The objective of this study was to determine the impact of obesity on breast cancer cell ERβ expression, which is currently unknown. We utilized an in vitro model of obesity in which breast cancer cells were exposed to patient serum pooled by body mass index category (obese (OB: ≥30 kg/m2; normal weight (N: 18.5-24.9 kg/m2. Four human mammary tumor cell lines representing the major breast cancer subtypes (SKBR3, MCF-7, ZR75, MDA-MB-231 and mammary tumor cells from MMTV-neu mice were used. ERβ expression, assessed by qPCR and western blotting, was suppressed in the two HER2-overexpressing cell lines (SKBR3, MMTV-neu following OB versus N sera exposure, but did not vary in the other cell lines. Expression of Bcl-2 and cyclin D1, two genes negatively regulated by ERβ, was elevated in SKBR3 cells following exposure to OB versus N sera, but this difference was eliminated when the ERβ gene was silenced with siRNA. Herceptin, a HER2 antagonist, and siRNA to HER2 were used to evaluate the role of HER2 in sera-induced ERβ modulation. SKBR3 cell treatment with OB sera plus Herceptin increased ERβ expression three-fold. Similar results were obtained when HER2 expression was silenced with siRNA. OB sera also promoted greater SKBR3 cell viability and growth, but this variance was not present when ERβ was silenced or the cells were modified to overexpress ERβ. Based on this data, we conclude that obesity-associated systemic factors suppress ERβ expression in breast cancer cells via a HER2-mediated pathway, leading to greater cell viability and growth. Elucidation of the mechanism(s mediating this effect could provide important insights into how ERβ expression is regulated as well as how obesity promotes a more aggressive disease.

  7. Association of beta 2 -adrenergic receptor gene polymorphisms and nocturnal asthma in Saudi patients

    Directory of Open Access Journals (Sweden)

    Al-Rubaish Abdullah


    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

  8. Highly effective recognition of carbohydrates by phenanthroline-based receptors: alpha- versus beta-anomer binding preference. (United States)

    Mazik, Monika; Hartmann, Andrè; Jones, Peter G


    (1)H NMR spectroscopic titrations in competitive and non-competitive media, as well as binding studies in two-phase systems, such as phase transfer of sugars from aqueous into organic solvents and dissolution of solid carbohydrates in apolar media revealed both highly effective recognition of neutral carbohydrates and interesting binding preferences of an acyclic phenanthroline-based receptor 1. Compared to the previously described acyclic receptors, compound 1 displays significantly higher binding affinities, the rare capability to extract sugars from water into non-polar organic solutions and alpha- versus beta-anomer binding preference in the recognition of glycosides, which differs from those observed for other receptor systems. X-ray crystallographic investigations revealed the presence of water molecules in the binding pocket of 1 that are engaged in the formation of hydrogen-bonding motifs similar to those suggested by molecular modelling for the sugar OH groups in the receptor-sugar complexes. The molecular modelling calculations, synthesis, crystal structure and binding properties of 1 are described and compared with those of the previously described receptors.

  9. 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. (United States)

    Kleuser, Burkhard; Malek, Daniela; Gust, Ronald; Pertz, Heinz H; Potteck, Henrik


    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.

  10. Treatment of Type 2 Diabetes by Free Fatty Acid Receptor Agonists


    Kenneth R. Watterson; Hudson, Brian D.; Ulven, Trond; Milligan, Graeme


    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 been developed as potential treatments for type 2 diabetes (T2D). In particular, clinical studies show that Fasiglifam, an agonist of the long chain FFA receptor, FFA1, improved glycaemic control an...

  11. Acquired resistance of Nocardia brasiliensis to clavulanic acid related to a change in beta-lactamase following therapy with amoxicillin-clavulanic acid. (United States)

    Steingrube, V A; Wallace, R J; Brown, B A; Pang, Y; Zeluff, B; Steele, L C; Zhang, Y


    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

  12. 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


    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.

  13. Central blockade of melanocortin receptors attenuates the metabolic and locomotor responses to peripheral interleukin-1beta administration. (United States)

    Whitaker, Keith W; Reyes, Teresa M


    Loss of appetite and cachexia is an obstacle in the treatment of chronic infection and cancer. Proinflammatory cytokines released from activated immune cells and acting in the central nervous system (CNS) are prime candidates for mediating these metabolic changes, potentially affecting both energy intake as well as energy expenditure. The effect of intravenous administration of two proinflammatory cytokines, interleukin (IL)-1beta (15 microg/kg) and tumor necrosis factor (TNF)-alpha (10 microg/kg), on food and water intake, locomotor activity, oxygen consumption (VO2), and respiratory exchange ratio (RER) was evaluated. The two cytokines elicited a comparable decrease in food intake and activated similar numbers of cells in the paraventricular nucleus of the hypothalamus (PVH), a region that plays a critical role in the regulation of appetite and metabolism (determined via expression of the immediate early gene, c-fos). However, only IL-1beta reduced locomotion and RER, and increased VO2, while TNF-alpha was without effect. To examine the role of the melanocortins in mediating IL-1beta- induced metabolic changes, animals were pretreated centrally with a melanocortin receptor antagonist, HS014. Pretreatment with HS014 blocked the effect of IL-1beta on food intake and RER at later time points (beyond 8 h post injection), as well as the hypoactivity and increased metabolic rate. Further, HS014 blocked the induction of Fos-ir in the PVH. These data highlight the importance of the melanocortin system, particularly within the PVH, in mediating a broad range of metabolic responses to IL-1beta.

  14. Determination of estrogen receptor {beta}-mediated estrogenic potencies of hydroxylated PCBS by a yeast two-hybrid assay

    Energy Technology Data Exchange (ETDEWEB)

    Kuroki, H.; Kumate, M.; Nakaoka, H.; Yonekura, S. [Daiichi Coll. of Pharmaceutical Sciences, Fukuoka (Japan); Nishikawa, J.; Nishihara, T. [Osaka Univ., Osaka (Japan)


    Several environmental phenolic chemicals such as Nonylphenol and Bisphenol A (BPA) have been previously shown to possess estrogenic properties. In the previous paper, we have investigated the estrogenic activity of a series of hydroxylated PCBs (OH-PCBs) by a yeast two-hybrid assay (estrogen receptor{alpha} (ER{alpha}) -TIF2), in which the expression of estrogenic activity is based on the interaction of chemicals with ER{alpha}, and demonstrated that 4'-OH-CB30 and 4'-OH-CB61 are more estrogenic than BPA, one of the environmental estrogens. We have showed that one chlorine substitution adjacent to 4-OH at 3- or 5-position significantly reduces the ER{alpha}-mediated estrogenic activity of 4-OH-PCBs. Thus, 4'-OH-CB25 and 4-OH-CB56 showed a very weak estrogenicity. We have also showed that 4-OH-PCBs with two chlorine substitutions adjacent to 4-OH at 3- and 5-position such as 4'-OH-CB79 (hydroxylated metabolite of CB77) and persistent 4-OH-PCBs retained in human blood (4-OH-CB107, 4-OH-CB146 and 4-OH-CB187) have no ER{alpha}-mediated estrogenic activity. ER is known to have two subtypes, namely ER{alpha} and ER{beta} and it is reported that ligand, some agonist and antagonist have a different binding affinity for ER{alpha} and ER{beta}. However, there is limited information on ER{beta}-mediated endocrine disrupting potency. In this study, we examined the ER{beta}-mediated estrogenic activity of a series of OH-PCBs, including environmentally relevant 4-OH-PCBs by a yeast two-hybrid assay (ER{beta}-TIF2).

  15. 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


    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.

  16. The orphan G protein-coupled receptor GPR40 is activated by medium and long chain fatty acids. (United States)

    Briscoe, Celia P; Tadayyon, Mohammad; Andrews, John L; Benson, William G; Chambers, Jon K; Eilert, Michelle M; Ellis, Catherine; Elshourbagy, Nabil A; Goetz, Aaron S; Minnick, Dana T; Murdock, Paul R; Sauls, Howard R; Shabon, Usman; Spinage, Lisa D; Strum, Jay C; Szekeres, Philip G; Tan, Kong B; Way, James M; Ignar, Diane M; Wilson, Shelagh; Muir, Alison I


    GPR40 is a member of a subfamily of homologous G protein-coupled receptors that include GPR41 and GPR43 and that have no current function or ligand ascribed. Ligand fishing experiments in HEK293 cells expressing human GPR40 revealed that a range of saturated and unsaturated carboxylic acids with carbon chain lengths greater than six were able to induce an elevation of [Ca(2+)](i), measured using a fluorometric imaging plate reader. 5,8,11-Eicosatriynoic acid was the most potent fatty acid tested, with a pEC(50) of 5.7. G protein coupling of GPR40 was examined in Chinese hamster ovary cells expressing the G alpha(q/i)-responsive Gal4-Elk1 reporter system. Expression of human GPR40 led to a constitutive induction of luciferase activity, which was further increased by exposure of the cells to eicosatriynoic acid. Neither the constitutive nor ligand-mediated luciferase induction was inhibited by pertussis toxin treatment, suggesting that GPR40 was coupled to G alpha(q/11.) Expression analysis by quantitative reverse transcription-PCR showed that GPR40 was specifically expressed in brain and pancreas, with expression in rodent pancreas being localized to insulin-producing beta-cells. These data suggest that some of the physiological effects of fatty acids in pancreatic islets and brain may be mediated through a cell-surface receptor.

  17. Biological roles and therapeutic potential of hydroxy-carboxylic acid receptors

    Directory of Open Access Journals (Sweden)

    Kashan eAhmed


    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.

  18. Estradiol-induced modulation of estrogen receptor-beta and GABA within the adult neocortex: a potential transsynaptic mechanism for estrogen modulation of BDNF. (United States)

    Blurton-Jones, Mathew; Tuszynski, Mark H


    Estrogen influences brain-derived neurotrophic factor (BDNF) expression in the neocortex. However, BDNF-producing cortical neurons do not express detectable levels of nuclear estrogen receptors; instead, the most abundant cortical nuclear estrogen receptor, ER-beta, is present in GABAergic neurons, prompting us to test the hypothesis that estrogen effects on BDNF are mediated via cortical inhibitory interneurons. Adult female ovariectomized rats were provided acute estrogen replacement and the number of cortical GABA, ER-beta, and ER-beta/GABA double-labeled neurons was examined. Within 48 hours of injection of 17-beta-estradiol, the number of perirhinal neurons double-labeled for ER-beta/GABA was reduced by 28% (PBDNF-expressing cells, brain sections were double- or triple-labeled for ER-beta, GABAergic, and BDNF immunomarkers. The findings indicated that ER-beta-bearing inhibitory neurons project onto other GABAergic neurons that lack nuclear estrogen receptors; these inhibitory neurons in turn innervate BDNF-expressing excitatory cells. High estrogen states reduce cortical GABA levels, presumably releasing inhibition on BDNF-expressing neurons. This identifies a putative two-step transsynaptic mechanism whereby estrogen availability modulates expression of inhibitory transmitters, resulting in increased BDNF expression.

  19. The structure, rearrangement, and ontogenic expression of DB and JB gene segments of the Mexican axolotl T-cell antigen receptor beta chain (TCRB). (United States)

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


    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.

  20. Experimental and theoretical studies on the inclusion complexation of syringic acid with alpha-, beta-, gamma- and heptakis(2,6-di-O-methyl)-beta-cyclodextrin. (United States)

    Song, Le Xin; Wang, Hai Ming; Xu, Peng; Yang, Yan; Zhang, Zi Qiang


    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.

  1. Oral Administration of a Retinoic Acid Receptor Antagonist Reversibly Inhibits Spermatogenesis in Mice


    Chung, Sanny S. W.; Wang, Xiangyuan; Roberts, Shelby S.; Stephen M Griffey; Reczek, Peter R.; Wolgemuth, Debra J.


    Meeting men's contraceptive needs, orally administered retinoic acid receptor antagonists represent new lead molecules in developing non-hormonal, reversible male contraceptives without adverse side effects.

  2. 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: [Brookhaven National Laboratory, Upton, NY 11973 (United States)


    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.

  3. Human recombinant macrophage inflammatory protein-1 alpha and -beta and monocyte chemotactic and activating factor utilize common and unique receptors on human monocytes. (United States)

    Wang, J M; Sherry, B; Fivash, M J; Kelvin, D J; Oppenheim, J J


    The human macrophage inflammatory proteins-1 alpha and -beta (MIP-1 alpha and -beta), which are also known as LD78 and ACT2, respectively, are distinct but highly related members of the chemoattractant cytokine (chemokine) family. rMIP-1 alpha and -beta labeled with 125I specifically bind to human peripheral blood monocytes, the monocytic cell line THP-1, peripheral blood T cells, and the YT cell line. Steady state binding experiments revealed approximately 3000 high affinity binding sites/cell for MIP-1 alpha on human monocytes and on THP-1 cells, with Kd values of 383 pM and 450 pM, respectively. Human MIP-1 alpha and -beta had nearly identical affinities for the binding sites and each competed equally well for binding. Human monocyte chemotactic and activating factor (MCAF), a member of the same chemokine family, consistently displaced about 25% of human MIP-1 alpha and -beta binding on monocytes but not on YT cells, which did not bind MCAF. On the other hand, human rMIP-1 alpha and -beta partially inhibited binding of radiolabeled MCAF to monocytes. Both MIP-1 alpha and -beta were chemotactic for human monocytes. Preincubation of monocytes with human rMIP-1 alpha or -beta markedly reduced cell migration towards the other cytokine, whereas preincubation with human rMCAF only partially desensitized the monocyte chemotaxis response to human rMIP-1 alpha or -beta. These data suggest the existence of three subtypes of receptors, i.e., one unique receptor shared by MIP-1 alpha and -beta, a second unique receptor for MCAF, and a third species that recognizes both MCAF and MIP-1 peptides.

  4. Biosensor analysis of dynamics of interleukin 5 receptor subunit beta(c) interaction with IL5:IL5R(alpha) complexes. (United States)

    Scibek, Jeffery J; Evergren, Emma; Zahn, Stefan; Canziani, Gabriela A; Van Ryk, Donald; Chaiken, Irwin M


    To gain insight into IL5 receptor subunit recruitment mechanism, and in particular the experimentally elusive pathway for assembly of signaling subunit beta(c), we constructed a soluble beta(c) ectodomain (s(beta)(c)) and developed an optical biosensor assay to measure its binding kinetics. Functionally active s(beta)(c) was anchored via a C-terminal His tag to immobilized anti-His monoclonal antibodies on the sensor surface. Using this surface, we quantitated for the first time direct binding of s(beta)(c) to IL5R(alpha) complexed to either wild-type or single-chain IL5. Binding was much weaker if at all with either R(alpha) or IL5 alone. Kinetic evaluation revealed a moderate affinity (0.2-1 microM) and relatively fast off rate for the s(beta)(c) interaction with IL5:R(alpha) complexes. The data support a model in which beta(c) recruitment occurs with preformed IL5:R(alpha) complex. Dissociation kinetics analysis suggests that the IL5-alpha-beta(c) complex is relatively short-lived. Overall, this study solidifies a model of sequential recruitment of receptor subunits by IL5, provides a novel biosensor binding assay of beta(c) recruitment dynamics, and sets the stage for more advanced characterization of the roles of structural elements within R(alpha), beta(c), and cytokines of the IL5/IL3/GM-CSF family in receptor recruitment and activation.

  5. 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: [Department of Molecular and Biochemical Nutrition, Graduate School of Human Life Science, Osaka City University, Osaka 558-8585 (Japan)


    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.


    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 ...

  7. Novel 4-(piperidin-4-yl)-1-hydroxypyrazoles as gamma-aminobutyric acidA receptor ligands

    DEFF Research Database (Denmark)

    Møller, Henriette A; Sander, Tommy; Kristensen, Jesper Langgaard;


    A series of substituted 1-hydroxypyrazole analogues of the GABA(A) receptor partial agonist 5-(4-piperidyl)-3-isoxazolol (4-PIOL) have been synthesized and pharmacologically characterized. Several of the analogues displayed K(i) in the low nanomolar range at the native GABA(A) receptors and potent...... antagonism of the alpha(1)beta(2)gamma(2) receptor. It appears that several regions situated in proximity to the core of the orthosteric binding site of the GABA(A) receptor are able to accommodate large hydrophobic substituents....

  8. Evaluation of beta-naphthoxyacetic acid for mutagenic activity in the Salmonella/mammalian microsome assay. (United States)

    Rashid, K A; Mumma, R O


    Beta-naphthoxyacetic acid (BNOA) is used as a plant growth regulator on tomatoes and strawberries. It is the active ingredient in Blossom-Set and Berry-Set, two plant hormone sprays for fruit-set. The mutagenic activity of BNOA was evaluated in four strains of Salmonella typhimurium (TA97, TA98, TA100 and TA1535) in the presence and absence of liver microsomal and cytosolic enzymes derived from Aroclor induced rats. BNOA did not produce any significant increase (p less than 0.05) in the reversion of any of the four tester strains in the standard plate incorporation assay. Results of the agar overlay toxicity tests indicates that the chemical shows toxic effects at concentrations above 500 micrograms/plate. It was concluded that under the conditions of these tests, BNOA did not exhibit any mutagenic activity.

  9. Expression of estrogen receptors alpha and beta in the corpus luteum and uterus from non-pregnant and pregnant llamas. (United States)

    Powell, Susan A; Smith, Bradford B; Timm, Karen I; Menino, Alfred R


    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.

  10. [Adrenergic beta-2 receptors and cyclic AMP in lymphocytes and their relationship to uterine contractility]. (United States)

    von Mandach, U


    It is especially in the long-term application where the pharmacodynamics of the betamimetics determine their effectiveness. According to the time and dosis, there is a decrease in the density and function of the beta 2-adrenoceptors (desensitization). Clinically, this means a loss of effectiveness. This study investigated whether in the course of a normal pregnancy (n = 22) there is a change in the effectiveness of the betamimetics, as expressed by a change in the number of beta 2-adrenoceptors or their function. The results show a 50% decrease in the number of beta 2-adrenoceptors to the 36th gestational week and an increase to initial values after delivery. A similar pattern is found for the function of the beta 2-adrenoceptors (cyclic AMP). The implications for the uterus might be that, with advancing pregnancy, it becomes less prone to relaxation and that the betaadrenergic system, as a mechanism supporting prepare the way for delivery at term, becomes less significant. For tocolysis with betamimetics, the decrease of the beta 2-adrenoceptor density means that, with increasing gestational age, the responsiveness of the uterus to betamimetics decreases.

  11. Fine specificity of monoclonal antibodies directed at human T cell receptor variable regions: comparison with oligonucleotide-driven amplification for evaluation of V beta expression. (United States)

    Diu, A; Romagné, F; Genevée, C; Rocher, C; Bruneau, J M; David, A; Praz, F; Hercend, T


    Seven distinct anti-human T cell receptor (TcR) V region monoclonal antibodies (mAb) were generated by immunizing mice with either human T cell lines or transfected murine cells expressing human TcR V beta genes. The specificity of these reagents was determined as follows: T cells recognized by each mAb were purified from the peripheral blood of healthy donors and TcR transcripts expressed in these cells were analyzed using oligonucleotide-driven amplification and cDNA sequencing. Four mAb were found to delineate the V beta 3, V beta 8, V beta 17 and V beta 19 subfamilies, respectively. The remaining reagents recognize subsets within the V beta 2, V beta 5 and V beta 13 subfamilies. Reactivity of the mAb with circulating T cells from 18 unrelated healthy individuals was determined. Limited variability was found from an individual to another. In four donors, mAb staining was compared to oligonucleotide-driven amplification for evaluation of V beta 3, V beta 8, V beta 17 and V beta 19 subfamily expression in the peripheral blood. Although the V gene subfamily-specific oligonucleotides used in this study belong to a carefully controlled series, our results show that this method does not give an accurate estimate of the percentage of peripheral T cells expressing a given TcR beta chain. The present data confirm the necessity to establish a complete set of well-characterized monoclonal reagents to study human T cell responses.

  12. Beta-2 receptor antagonists for traumatic brain injury: a systematic review of controlled trials in animal models. (United States)

    Ker, K; Perel, P; Blackhall, K


    A systematic review and meta-analysis of controlled trials was undertaken to assess the effects of beta-2 receptor antagonists in animal models of traumatic brain injury (TBI). Database and reference list searches were performed to identify eligible studies. Outcome data were extracted on functional status, as measured by the grip test or neurological severity score (NSS), and cerebral edema, as measured by brain water content (BWC). Data were pooled using the random-effects model. Seventeen controlled trials involving 817 animals were identified. Overall methodological quality was poor. Results from the grip test suggest that the treatment group maintained grip for a longer period than the control group; pooled weighted mean difference (WMD) = 8.28 (95% CI 5.78-10.78). The treatment group was found to have a lower NSS (i.e., better neurological function); pooled WMD =-3.28 (95% CI -4.72 to -1.85). Analysis of the cerebral edema data showed that the treatment group had a lower BWC than the control; pooled WMD =-0.42 (95% CI -0.59 to -0.26). There was evidence of statistical heterogeneity between comparisons for all outcomes. Evidence for small study effects was found for the grip test and BWC outcomes. The evidence from animal models of TBI suggests that beta-2 receptor antagonists can improve functional outcome and lessen cerebral edema. However, the poor methodological quality of the included studies and presence of small study effects may have influenced these findings.

  13. Pavlovian conditioning of morphine-induced alterations of immune status: evidence for peripheral beta-adrenergic receptor involvement. (United States)

    Coussons-Read, M E; Dykstra, L A; Lysle, D T


    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.

  14. 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.

  15. "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


    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.

  16. Tannic Acid Preferentially Targets Estrogen Receptor-Positive Breast Cancer

    Directory of Open Access Journals (Sweden)

    Brian W. Booth


    Full Text Available Research efforts investigating the potential of natural compounds in the fight against cancer are growing. Tannic acid (TA belongs to the class of hydrolysable tannins and is found in numerous plants and foods. TA is a potent collagen cross-linking agent; the purpose of this study was to generate TA-cross-linked beads and assess the effects on breast cancer cell growth. Collagen beads were stable at body temperature following crosslinking. Exposure to collagen beads with higher levels of TA inhibited proliferation and induced apoptosis in normal and cancer cells. TA-induced apoptosis involved activation of caspase 3/7 and caspase 9 but not caspase 8. Breast cancer cells expressing the estrogen receptor were more susceptible to the effects of TA. Taken together the results suggest that TA has the potential to become an anti-ER+ breast cancer treatment or preventative agent.

  17. Benzopyrans as selective estrogen receptor beta agonists (SERBAs). Part 3: synthesis of cyclopentanone and cyclohexanone intermediates for C-ring modification. (United States)

    Richardson, Timothy I; Dodge, Jeffrey A; Durst, Gregory L; Pfeifer, Lance A; Shah, Jikesh; Wang, Yong; Durbin, Jim D; Krishnan, Venkatesh; Norman, Bryan H


    Benzopyrans are selective estrogen receptor (ER) beta agonists (SERBAs), which bind the ER subtypes alpha and beta in opposite orientations. Here we describe the syntheses of cyclopentanone and cyclohexanone intermediates for SAR studies of the C-ring on the benzopyran scaffold. Modification of the C-ring disrupts binding to ERalpha, thus improving ERbeta selectivity up to 100-fold. X-ray cocrystal structures confirm previously observed binding modes.

  18. 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. (United States)

    Sloboda, Deborah M; Moss, Timothy J M; Li, Shaofu; Matthews, Stephen G; Challis, John R G; Newnham, John P


    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.

  19. Beta-arrestin biased agonism/antagonism at cardiovascular seven transmembrane-spanning receptors. (United States)

    Lymperopoulos, Anastasios


    Heptahelical, G protein-coupled or seven transmembrane-spanning receptors, such as the β-adrenergic and the angiotensin II type 1 receptors, are the most diverse and therapeutically important family of receptors in the human genome, playing major roles in the physiology of various organs/tissues including the heart and blood vessels. Ligand binding activates heterotrimeric G proteins that transmit intracellular signals by regulating effector enzymes or ion channels. G protein signaling is terminated, in large part, by phosphorylation of the agonist-bound receptor by the G-protein coupled receptor kinases (GRKs), followed by βarrestin binding, which uncouples the phosphorylated receptor from the G protein and subsequently targets the receptor for internalization. As the receptor-βarrestin complex enters the cell, βarrestin-1 and -2, the two mammalian βarrestin isoforms, serve as ligand-regulated scaffolds that recruit a host of intracellular proteins and signal transducers, thus promoting their own wave of signal transduction independently of G-proteins. A constantly increasing number of studies over the past several years have begun to uncover specific roles played by these ubiquitously expressed receptor adapter proteins in signal transduction of several important heptahelical receptors regulating the physiology of various organs/ systems, including the cardiovascular (CV) system. Thus, βarrestin-dependent signaling has increasingly been implicated in CV physiology and pathology, presenting several exciting opportunities for therapeutic intervention in the treatment of CV disorders. Additionally, the discovery of this novel mode of heptahelical receptor signaling via βarrestins has prompted a revision of classical pharmacological concepts such as receptor agonism/antagonism, as well as introduction of new terms such as "biased signaling", which refers to ligand-specific activation of selective signal transduction pathways by the very same receptor. The

  20. 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))


    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).

  1. Rigid nonproteinogenic cyclic amino acids as ligands for glutamate receptors: trans-tris(homoglutamic) acids

    DEFF Research Database (Denmark)

    Meyer, Udo; Bisel, Philippe; Bräuner-Osborne, Hans;


    The second-generation asymmetric synthesis of the trans-tris(homoglutamic) acids reported herein proceeds via Strecker reaction of chiral ketimines, obtained from condensation of racemic 2-ethoxycarbonylmethylcyclopentanone and commercially available (S)- and (R)-1-phenylethylamine, respectively......) yielded diastereomeric mixtures of secondary alpha-amino amido-esters, which after separation were hydrogenolyzed and hydrolyzed each to the enantiomeric trans-1-amino-2-carboxymethylcyclopentanecarboxylic acids. Their configuration was completely established by NMR methods, CD spectra, and X-ray analysis...... of the trans-1S,2R-configured secondary alpha-amino amido-ester. In receptor binding assays and functional tests, trans-1S,2R-1-amino-2-carboxymethylcyclopentanecarboxylic acid hydrochloride was found to behave as a selective mGluR(2)-antagonist without relevant binding properties at iGluRs....

  2. 1,2,3-triazolyl amino acids as AMPA receptor ligands

    DEFF Research Database (Denmark)

    Stanley, Nathan J.; Pedersen, Daniel Sejer; Nielsen, Birgitte


    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...

  3. Novel Confocal Microscopic and Flow Cytometric Based Assays to Visualize and Detect the (Beta)2-Adrenergic Receptor in Human Lymphocyte and Mononuclear Cell Populations (United States)

    Salicru, A. N.; Crucian, B. E.; Nelman, M. A.; Sams, C. F.; Actor, J. K.; Marshall, G. D.


    The data show that immunophenotyping of leukocyte populations with (beta)2AR is possible with the commercially available Ab, although the FC assay is limited to the IST as a result of the Ab binding site to the intracellular C-terminus of the 2AR. The FC assay has applications for measuring alterations in total (beta)2AR in human leukocyte populations as changes in fluorescence. In addition, CM confirms that both surface and intracellular compartments stain positively for the (beta)2AR and can be used for qualitative assays that screen for changes in receptor compartmentalization and localization.

  4. Increased concentrations of interleukin-6 and interleukin-1 receptor antagonist and decreased concentrations of beta-2-glycoprotein I in Gambian children with cerebral malaria

    DEFF Research Database (Denmark)

    Jakobsen, P H; McKay, V; Morris-Jones, S D;


    concentrations of anti-PI antibodies and the PI-binding serum protein beta-2-glycoprotein I. We found increased concentrations of IL-6, sIL-6R, IL-1ra, and some immunoglobulin M antibodies against PI in children with cerebral malaria, but those who died had decreased concentrations of beta-2-glycoprotein I. We...... conclude that increased concentrations of cytokines and soluble cytokine receptors represent a normal host response to P. falciparum infections but that excessive secretion of cytokines like IL-6 may predispose to cerebral malaria and a fatal outcome while beta-2-glycoprotein I may protect against a fatal...

  5. Pharmacological Tool Compounds for the Free Fatty Acid Receptor 4 (FFA4/GPR120)

    DEFF Research Database (Denmark)

    Hansen, Steffen V F; Ulven, Trond


    The free fatty acid receptor 4 (FFA4), also known as GPR120, is a G protein-coupled receptor that is activated by long-chain fatty acids and that has been associated with regulation of appetite, release of insulin controlling hormones, insulin sensitization, anti-inflammatory and potentially anti...

  6. 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


    Akiyoshi Takahashi; Perry Davis; Christina Reinick; Kanta Mizusawa; Tatsuya Sakamoto; Dores, Robert M.


    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 ...

  7. Poly (γ-glutamic acid)/beta-TCP nanocomposites via in situ copolymerization: Preparation and characterization. (United States)

    Shu, Xiu-Lin; Shi, Qing-Shan; Feng, Jin; Yang, Yun-Hua; Zhou, Gang; Li, Wen-Ru


    A series biodegradable poly (γ-glutamic acid)/beta-tricalcium phosphate (γ-PGA/TCP) nanocomposites were prepared which were composed of poly-γ-glutamic acid polymerized in situ with β-tricalcium phosphate and physiochemically characterized as bone graft substitutes. The particle size via dynamic light scattering, the direct morphological characterization via transmission electron microscopy and field emission scanning electron microscope, which showed that γ-PGA and β-TCP were combined compactly at 80℃, and the γ-PGA/TCP nanocomposites had homogenous and nano-sized grains with narrow particle size distributions. The water uptake and retention abilities, in vitro degradation properties, cytotoxicity in the simulated medium, and protein release of these novel γ-PGA/TCP composites were investigated. Cell proliferation in composites was nearly twice than β-TCP when checked in vitro using MC3T3 cell line. We also envision the potential use of γ-PGA/TCP systems in bone growth factor or orthopedic drug delivery applications in future bone tissue engineering applications. These observations suggest that the γ-PGA/TCP are novel nanocomposites with great potential for application in the field of bone tissue engineering.

  8. 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.


    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

  9. The Influence of Stromal Transforming Growth Factor-(beta) Receptor Signaling on Mouse Mammary Neoplasia (United States)


    responsiveness to TGF-BETA in the stroma effects tumor development transgenic and wild type mice were given pituitary isografts followed by zinc water and...pituitary isograft , zinc and DMBA) while only one tumor has arisen in the control group. To date, only two tumors have arisen in the transgenic mice

  10. The Role of beta-TrCP Ubiquitin Ligase Receptor in the Development of Breast Cancer (United States)


    protein betaTrcp1 in mammary gland development and tumorigenesis. Mol Cell Biol 2004;24(18):8184-94. 7. Bhatia N, Herter JR, Slaga TJ, Fuchs SY...Inhibition of HOS expression and activities by Wnt pathway, Oncogene, 2002, 21, 856-860. 16. Bhatia N., Herter J. R., Slaga T. J., Fuchs S. Y., and

  11. Interleukin-4, interleukin-10, and interleukin-1-receptor antagonist but not transforming growth factor-beta induce ramification and reduce adhesion molecule expression of rat microglial cells. (United States)

    Wirjatijasa, Florentina; Dehghani, Faramarz; Blaheta, Roman A; Korf, Horst-Werner; Hailer, Nils P


    The activity of microglial cells is strictly controlled in order to maintain central nervous system (CNS) immune privilege. We hypothesized that several immunomodulatory factors present in the CNS parenchyma, i.e., the Th2-derived cytokines interleukin (IL)-4 and IL-10, interleukin-1-receptor-antagonist (IL-1-ra), or transforming growth factor (TGF)-beta can modulate microglial morphology and functions. Microglial cells were incubated with IL-4, IL-10, IL-1-ra, TGF-beta, or with astrocyte conditioned media (ACM) and were analyzed for morphological changes, expression of intercellular adhesion molecule (ICAM)-1, and secretion of IL-1beta or tumor necrosis factor (TNF)-alpha. Whereas untreated controls showed an amoeboid morphology both Th2-derived cytokines, IL-1-ra, and ACM induced a morphological transformation to the ramified phenotype. In contrast, TGF-beta-treated microglial cells showed an amoeboid morphology. Even combined with the neutralizing antibodies against IL-4, IL-10, or TGF-beta ACM induced microglial ramification. Furthermore, ACM did not contain relevant amounts of IL-4 and IL-10, as measured by enzyme-linked immunosorbent assay (ELISA). Flow cytometry showed that lipopolysaccharide (LPS)-induced ICAM-1-expression on microglial cells was strongly suppressed by ACM, significantly modulated by IL-4, IL-10, or IL-1-ra, but not influenced by TGF-beta. The LPS-induced secretion of IL-1beta and TNF-alpha was only reduced after application of ACM, whereas IL-4 or IL-10 did not inhibit IL-1beta- or TNF-alpha secretion. TGF-beta enhanced IL-1beta- but not TNF-alpha secretion. In summary, we demonstrate that IL-4, IL-10, and IL-1-ra induce microglial ramification and reduce ICAM-1-expression, whereas the secretion of proinflammatory cytokines is not prevented. TGF-beta has no modulating effects. Importantly, unidentified astrocytic factors that are not identical with IL-4, IL-10, or TGF-beta possess strong immunomodulatory properties.

  12. Interaction of selected vasodilating beta-blockers with adrenergic receptors in human cardiovascular tissues

    Energy Technology Data Exchange (ETDEWEB)

    Monopoli, A.; Forlani, A.; Bevilacqua, M.; Vago, T.; Norbiato, G.; Bertora, P.; Biglioli, P.; Alamanni, F.; Ongini, E. (Essex Italia, Subsidiary of Schering-Plough, Milan)


    beta- And alpha 1-adrenoceptor antagonist properties of bufuralol, carvedilol, celiprolol, dilevalol, labetalol, and pindolol were investigated in human myocardium and mammary artery using binding techniques and functional studies. In myocardial membranes, beta-adrenoceptor antagonists showed monophasic competition isotherms for (125I)pindolol binding with high affinity (Ki from 1-100 nM), except for celiprolol which displayed a biphasic competition isotherm (pKi = 6.4 +/- 0.06 for beta 1- and 4.8 +/- 0.07 for beta 2-adrenoceptors). Drug interactions with alpha 1-adrenoceptors were evaluated in human mammary artery by (3H)prazosin binding and by measuring contractile responses to norepinephrine (NE). Labetalol and carvedilol showed a moderate affinity for alpha 1-adrenoceptors (pKi = 6.2 +/- 0.01 and 6.1 +/- 0.06, respectively), and inhibited NE-induced contractions (pA2 = 6.93 +/- 0.23 and 8.64 +/- 0.24, respectively). Dilevalol, bufuralol, and pindolol displayed weak effect both in binding (Ki in micromolar range) and functional experiments (pA2 = 5.98, 5.54, and 6.23, respectively). Celiprolol did not show antagonist properties up to 100 microM in functional studies, but displayed a slight affinity for alpha 1-adrenoceptors in binding studies. The data indicate that the vasodilating activity of these beta-adrenoceptor antagonists is caused in some instances by an alpha 1-adrenoceptor antagonism (labetalol, carvedilol), whereas for the others alternative mechanisms should be considered.

  13. 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.;


    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 the apical or basolateral compartment. Using transgenic mice expressing fluorescent sensors specifically in L...... to either TLCA or TDCA. We conclude that the action of bile acids on GLP-1 secretion is predominantly mediated by GPBAR1 located on the basolateral L-cell membrane, suggesting that stimulation of gut hormone secretion may include postabsorptive mechanisms....

  14. [The expression of estrogen receptor alpha and beta in the intervention of different estrogens in rat bone metabolism]. (United States)

    Hou, Ning Ning; Zhu, Yi Min; Huang, He Feng


    In this present study, female rats were ovariectomized (OVX) as the models of osteoporosis. The aim is to determine the different mechanisms of estrogen receptor(ER) alpha and beta pathway in mediating estrogen to participate in trabecular bone metabolism, and to further explore the distinction of modulation on ER alpha or ER beta between estrogens with different components. Mature female Sprague-Dawley rats (n=40) were randomly divided into four groups: group Control (sham operated), group OVX (only ovariectomized), group CEE (OVX rats treated with conjugated equine estrogens) and group EV (OVX rats treated with estradiol valerate). Sham operation and OVX were performed 48 days (12 estrums) before different liquid diet. The rats in group Control and group OVX were orally administrated with physiological saline solution and the rats in group CEE or group EV were orally administrated with CEE or EV for 12 days (3 estrums) before sacrifice. Relative quantitative reverse transcription- polymerase chain reaction (RT-PCR) and western blot techniques were utilized to compare the levels of ER alpha and ER beta mRNA and proteins in trabecular bone among groups. The results showed that in rat trabecular bone of group Control, the expression of ER alpha protein (1.433 +/- 0.250) was significantly higher than that of ER beta(0.687 +/- 0.120), whereas the ER alpha mRNA (0.285 +/- 0.033) was much lower than ERbeta mRNA(0.590 +/- 0.044). Following OVX, the levels of ER alpha protein (0.685 +/- 0.103) declined significantly, whereas mRNA levels (0.405 +/- 0.036) markedly increased. Both the protein (1.091 +/- 0.078) and mRNA (0.729 +/- 0.030) levels of ER beta significantly increased after OVX. After treatment with CEE, the expression of ER beta protein (0.583 +/- 0.129) and mRNA (0.618 +/- 0.043) were markedly down-regulated compared with group OVX. After treatment with EV, the ER alpha protein expression (1.272 +/- 0.247) was markedly up-regulated, while ERa mRNA (0.277 +/- 0

  15. 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: [Division of Bio-function Dynamics Imaging, RIKEN Center for Life Science Technologies, 6-7-3 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo 650-0047 (Japan)


    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.

  16. Selective Chemical Conversion of Sugars in Aqueous Solutions without Alkali to Lactic Acid Over a Zn-Sn-Beta Lewis Acid-Base Catalyst (United States)

    Dong, Wenjie; Shen, Zheng; Peng, Boyu; Gu, Minyan; Zhou, Xuefei; Xiang, Bo; Zhang, Yalei


    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.

  17. Cytisine binds with similar affinity to nicotinic alpha4beta2 receptors on the cell surface and in homogenates. (United States)

    Zhang, Jessie; Steinbach, Joe Henry


    Cytisine and nicotine bound to specific sites in homogenates prepared from HEK 293 cells which stably express human neuronal nicotinic alpha4 and beta2 subunits. The number of sites was the same for both ligands and nicotine was a full competitive inhibitor of cytisine binding. However, when binding was done to intact cells the number of binding sites per cell for nicotine was approximately 4-fold the number of sites for cytisine. Nicotine fully blocked cytisine binding, but cytisine only partially blocked nicotine binding to intact cells. When cells were permeabilized with saponin, the number of sites for nicotine was unchanged, while the number of sites for cytisine was increased, and cytisine was able to fully block nicotine binding. These data indicate that cytisine binds only to surface receptors on intact cells. The apparent affinity of cytisine for surface receptors (K(d)=0.8 nM) was not significantly different from that for receptors in the cell homogenate (0.3 nM).

  18. 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.

  19. Properties of a fluorescent bezafibrate derivative (DNS-X). A new tool to study peroxisome proliferation and fatty acid beta-oxidation. (United States)

    Berlot, J P; Lutz, T; Cherkaoui Malki, M; Nicolas-Frances, V; Jannin, B; Latruffe, N


    The first peroxisome proliferator-activated receptor (PPAR) was cloned in 1990 by Issemann and Green. Many studies have reported the importance of this receptor in the control of gene expression of enzymes involved in lipid metabolic pathways including mitochondrial and peroxisomal fatty acid beta-oxidation, lipoprotein structure [apolipoprotein (apo) A2, apo CIII], and fatty acid synthase. By using radiolabeled molecules, it was shown that peroxisome proliferators bind and activate PPAR. As an alternative method, we developed a fluorescent dansyl (1-dimethylaminonaphthalene-5-sulfonyl) derivative peroxisome proliferator from bezafibrate (DNS-X), a hypolipidemic agent that exhibits an in vitro peroxisome proliferative activity on rat Fao-hepatic derived cultured cells. However, until now, the effect of this new compound on the liver of animals and subcellular localization was unknown. In addition to in vivo rat studies, we present a more efficient large-scale technique of DNS-X purification. Treating rats (DNS-X in the diet at 0.3% w/w) for 6 d leads to a hepatomegaly and a marked increase in liver peroxisomal palmitoyl-CoA oxidase activity. We also developed a method to localize and quantify DNS-X in tissues or cell compartment organelles. The primarily cytosolic distribution of DNS-X was confirmed by direct visualization using fluorescence microscopy of cultured Fao cells. Finally, transfection assay demonstrated that DNS-X enhanced the PPAR alpha activity as well as other peroxisome proliferators do.

  20. 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


    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...... airway to IL-1beta induces up- and down-regulation of mRNA expression for Toll-IL-1 receptor signal molecules, with a significant increase in the expression of 16 genes that contribute to the development of airway inflammation and AHR. Understanding cytokine-induced activation of the Toll-IL-1 receptor...

  1. 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;


    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....

  2. 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


    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

  3. 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.


    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...... 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...

  4. 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: [School of Life Sciences and Biotechnology, Korea University, Seoul 136-701 (Korea, Republic of)


    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}.

  5. Analysis of beta, gamma, and delta T-cell receptor genes in mycosis fungoides and Sezary syndrome. (United States)

    Whittaker, S J; Smith, N P; Jones, R R; Luzzatto, L


    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

  6. OXA-18, a class D clavulanic acid-inhibited extended-spectrum beta-lactamase from Pseudomonas aeruginosa. (United States)

    Philippon, L N; Naas, T; Bouthors, A T; Barakett, V; Nordmann, P


    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

  7. Tetrazolyl isoxazole amino acids as ionotropic glutamate receptor antagonists: synthesis, modelling and molecular pharmacology. (United States)

    Frølund, Bente; Greenwood, Jeremy R; Holm, Mai M; Egebjerg, Jan; Madsen, Ulf; Nielsen, Birgitte; Bräuner-Osborne, Hans; Stensbøl, Tine B; Krogsgaard-Larsen, Povl


    Two 3-(5-tetrazolylmethoxy) analogues, 1a and 1b, of (RS)-2-amino-3-(3-hydroxy-5-methyl-4-isoxazolyl)propionic acid (AMPA), a selective AMPA receptor agonist, and (RS)-2-amino-3-(5-tert-butyl-3-hydroxy-4-isoxazolyl)propionic acid (ATPA), a GluR5-preferring agonist, were synthesized. Compounds 1a 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. Both analogues proved to be antagonists at all AMPA receptor subtypes, showing potencies (Kb=38-161 microM) similar to that of the AMPA receptor antagonist (RS)-2-amino-3-[3-(carboxymethoxy)-5-methyl-4-isoxazolyl]propionic acid (AMOA) (Kb=43-76 microM). Furthermore, the AMOA analogue, 1a, blocked two kainic acid receptor subtypes (GluR5 and GluR6/KA2), showing sevenfold preference for GluR6/KA2 (Kb=19 microM). Unlike the iGluR antagonist (S)-2-amino-3-[5-tert-butyl-3-(phosphonomethoxy)-4-isoxazolyl]propionic acid [(S)-ATPO], the corresponding tetrazolyl analogue, 1b, lacks kainic acid receptor effects. On the basis of docking to a crystal structure of the isolated extracellular ligand-binding core of the AMPA receptor subunit GluR2 and a homology model of the kainic acid receptor subunit GluR5, we were able to rationalize the observed structure-activity relationships.

  8. Farnesoid X receptor, the bile acid sensing nuclear receptor, in liver regeneration

    Directory of Open Access Journals (Sweden)

    Guodong Li


    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.

  9. Induction of transforming growth factor beta receptors following focal ischemia in the rat brain.

    Directory of Open Access Journals (Sweden)

    Gabriella Pál

    Full Text Available Transforming growth factor-βs (TGF-βs regulate cellular proliferation, differentiation, and survival. TGF-βs bind to type I (TGF-βRI and II receptors (TGF-βRII, which are transmembrane kinase receptors, and an accessory type III receptor (TGF-βRIII. TGF-β may utilize another type I receptor, activin-like kinase receptor (Alk1. TGF-β is neuroprotective in the middle cerebral artery occlusion (MCAO model of stroke. Recently, we reported the expression pattern of TGF-β1-3 after MCAO. To establish how TGF-βs exert their actions following MCAO, the present study describes the induction of TGF-βRI, RII, RIII and Alk1 at 24 h, 72 h and 1 mo after transient 1 h MCAO as well as following 24 h permanent MCAO using in situ hybridization histochemistry. In intact brain, only TGF-βRI had significant expression: neurons in cortical layer IV contained TGF-βRI. At 24 h after the occlusion, no TGF-β receptors showed induction. At 72 h following MCAO, all four types of TGF-β receptors were induced in the infarct area, while TGF-βRI and RII also appeared in the penumbra. Most cells with elevated TGF-βRI mRNA levels were microglia. TGF-βRII co-localized with both microglial and endothelial markers while TGF-βRIII and Alk1 were present predominantly in endothels. All four TGF-β receptors were induced within the lesion 1 mo after the occlusion. In particular, TGF-βRIII was further induced as compared to 72 h after MCAO. At this time point, TGF-βRIII signal was predominantly not associated with blood vessels suggesting its microglial location. These data suggest that TGF-β receptors are induced after MCAO in a timely and spatially regulated fashion. TGF-β receptor expression is preceded by increased TGF-β expression. TGF-βRI and RII are likely to be co-expressed in microglial cells while Alk1, TGF-βRII, and RIII in endothels within the infarct where TGF-β1 may be their ligand. At later time points, TGF-βRIII may also appear in glial cells

  10. [Central effects of five beta-adrenergic receptor blockers in healthy volunteers: a quantitative EEG study]. (United States)

    Sabot, C; Pechadre, J C; Beudin, P; Lauxerois, M; Trolese, J F; Kantelip, J P; Ducher, J L; Gibert, J


    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.

  11. 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: [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)


    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.

  12. Beta-alanine-oxalic acid (1:1) hemihydrate crystal: structure, 13C NMR and vibrational properties, protonation character. (United States)

    Godzisz, D; Ilczyszyn, M; Ilczyszyn, M M


    The crystal structure of beta-alanine-oxalic acid (1:1) hemihydrate complex has been reinvestigated by X-ray diffraction method at 293 K. Formation of monoclinic crystal system belonging to C2/c space group and consisting of semi-oxalate chains, diprotonated beta-alanine dimers and water molecules bonded to both these units is confirmed. New results are obtained for distances in the carboxylic groups and hydrogen bonds. These structural observations are used for protonation degree monitoring on the carboxylic oxygen atoms. They are in accordance with our vibrational study. The 13C NMR spectra provide insights into the solid structure of this complex, character of its hydrogen bonds and the beta-alanine protonation.

  13. Beta-CCT, a selective BZ-omega1 receptor antagonist, blocks the anti-anxiety but not the amnesic action of chlordiazepoxide in mice. (United States)

    Belzung, C; Le Guisquet, A M; Griebel, G


    The aim of this study was to test further the hypothesis that different benzodiazepine (BZ-omega) receptor subtypes may mediate anxiolytic and amnesic effects of BZ agonists, using the selective BZ-omega1 receptor antagonist beta-CCT (beta-carboline-3-carboxylate t-butyl-ester). Experiments were performed in Swiss mice using the elevated plus-maze anxiety test and two learning tasks - passive avoidance and the radial arm maze. In the elevated plus-maze test, beta-CCT (30 mg/kg, i.p.) completely abolished the increase in open-arm entries induced by the BZ chlordiazepoxide (5mg/kg, i.p.). Chlordiazepoxide decreased retention latency in the passive avoidance step-through procedure, and increased the number of errors in the radial arm maze. These effects were not modified by beta-CCT. Except for a slight, albeit significant, amnesic effect in the passive avoidance test, beta-CCT was devoid of intrinsic activity when administered alone. These results are in agreement with previous studies using selective BZ-omega1 agonists, and thus provide further evidence that BZ-omega1 receptors may be involved in the anxiolytic but not in the amnesic effects of BZ agonists.

  14. Characterization of bicuculline/baclofen-insensitive (rho-like) gamma-aminobutyric acid receptors expressed in Xenopus oocytes. II. Pharmacology of gamma-aminobutyric acidA and gamma-aminobutyric acidB receptor agonists and antagonists. (United States)

    Woodward, R M; Polenzani, L; Miledi, R


    Poly(A)+ RNA from mammalian retina expresses bicuculline/baclofen-insensitive gamma-aminobutyric acid (GABA) receptors in Xenopus oocytes with properties similar to those of homooligomeric GABA rho 1 receptors. The pharmacological profile of these rho-like receptors was extended by measuring sensitivities to various GABAA and GABAB receptor ligands. For direct comparison the same compounds were also assayed with GABAA receptors expressed by rat brain RNA. The potency sequence for heterocyclic GABA analogues at the GABA rho-like receptors was GABA (1.3) > muscimol (2.3) > isoguvacine (100) (approximate EC50 in parentheses; all EC50 and Kb values given in microM). Both muscimol and isoguvacine were partial agonists at the rho-like receptors. 4,5,6,7-Tetrahydroisoxazolo[5,4-c]pyridin-3-ol (Kb congruent to 32), piperidine-4-sulfonic acid (Kb congruent to 85), and isonipecotic acid (Kb congruent to 1000) acted primarily as competitive antagonists, showing little or no activity as agonists. The sulfonic acid GABA analogue 3-aminopropanesulfonic acid was also a competitive antagonist (Kb congruent to 20). Conformationally restricted GABA analogues trans- and cis-4-aminocrotonic acid (TACA and CACA) were agonists at the rho-like receptors. TACA (EC50 congruent to 0.6) had twice the potency of GABA and was 125 times more potent than CACA (EC50 congruent to 75). Z-3-(Amidinothio)propenoic acid, an isothiouronium analogue of GABA, had little activity as an agonist but instead acted as a competitive antagonist (Kb congruent to 20). At concentrations of > 100 microM, bicuculline did have some weak competitive inhibitory effects on the GABA rho-like receptors (Kb congruent to 6000), but it was at least 5000 times more potent at GABAA receptors. Strychnine (Kb congruent to 70) and SR-95531 (Kb congruent to 35) also were competitive inhibitors of the rho-like receptors but were, respectively, 20 and 240 times more potent at GABAA receptors. The GABAB receptor ligands baclofen

  15. 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;


    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...... by molecular mechanics calculations. Compound 7a possesses extra steric bulk and shows significant restriction of conformational flexibility compared to AMAA and 7c, which may be determining factors for the observed differences in biological activity. Although the nitrogen atom of quinolinic acid (6) has very...

  16. 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


    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.

  17. Evidence for a role of the 5-HT2C receptor in central lipopolysaccharide-, interleukin-1 beta-, and leptin-induced anorexia. (United States)

    von Meyenburg, Claudia; Langhans, Wolfgang; Hrupka, Brian J


    We examined the role of serotonin (5-HT) and the 5-HT(1A) and 5-HT(2C) receptors in the anorectic effects of centrally administered lipopolysaccharide (LPS), interleukin-1 beta (IL-1 beta), and leptin. Food intake was measured in rats after intracerebroventricular (ICV) injections of LPS (20 ng), IL-1 beta (10 ng), or leptin (1 microg) at lights out, followed by intraperitoneal (IP) injections of either the 5-HT(1A) autoreceptor agonist 8-hydroxy-2-(di-n-propylamino)tetraline (8-OH-DPAT) (125 microg/kg) or the 5-HT(2C) receptor antagonist SB 242084 (0.3 mg/kg) at the onset of anorexia. SB 242084 significantly attenuated the food intake reduction caused by all compounds (all Panorexia (Panorexia. Rats were injected intraperitoneally with either LPS (100 microg/kg) or IL-1 beta (2 microg/kg) at lights out, and 8-OH-DPAT (4 nmol) was administered directly into the median raphe nucleus at the onset of anorexia. Median raphe injections of 8-OH-DPAT significantly attenuated both IL-1 beta- and LPS-induced anorexia (both Panorexia. Our results also suggest that the midbrain raphe nuclei play a role in mediating the anorectic response to peripheral LPS and IL-1 beta.

  18. Activation of transgenic estrogen receptor-beta by selected phytoestrogens in a stably transduced rat serotonergic cell line. (United States)

    Amer, Dena A M; Kretzschmar, Georg; Müller, Nicole; Stanke, Nicole; Lindemann, Dirk; Vollmer, Günter


    Many flavonoids, a major group of phenolic plant-derived secondary metabolites, are known to possess estrogen-like bioactivities. However, little is known about their estrogenic properties in the central nervous system due to the lack of suitable cellular models expressing sufficient amounts of functional estrogen receptor beta (ERbeta). To overcome this deficit, we have created a cellular model, which is serotonergic in origin, to study properties of estrogenic substances by stably transducing RN46A-B14 cells derived from raphe nuclei region of the rat brain with a lentiviral vector encoding a human ERbeta. We clearly showed that the transgenic human ERbeta is a spontaneously expressed and a functional receptor. We have further assessed the estrogenicity of three different isoflavones and four different naringenin-type flavanones in this cell line utilizing a luciferase reporter gene assay. Genistein (GEN), Daidzein (DAI), Equol (EQ), Naringenin (NAR) and 8-prenylnaringenin (8-PN) showed strong estrogenic activity in a concentration-dependent manner as compared to 7-(O-prenyl)naringenin-4'-acetate (7-O-PN) which was only slightly estrogenic and 6-(1,1-dimethylallyl)naringenin (6-DMAN) that neither showed estrogenic nor anti-estrogenic activity in our model. All observed effects could be antagonized by the anti-estrogen fulvestrant. Moreover, co-treatment of cells with 17beta-estradiol (E2) and either GEN or DAI showed a slight additive effect as compared to EQ. On the other hand, 8-PN in addition to 7-O-PN, but not NAR and 6-DMAN, were able to slightly antagonize the responses triggered by E2. Our newly established cellular model may prove to be a useful tool in explicating basic physiological properties of ERbeta in the brain and may help unravel molecular and cellular mechanisms involved in serotonergic mood regulation by estrogen or potential plant-derived secondary metabolites.

  19. 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


    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.

  20. Polymorphism at the ovine beta3-adrenergic receptor locus: associations with birth weight, growth rate, carcass composition and cold survival. (United States)

    Forrest, R H; Hickford, J G H; Hogan, A; Frampton, C


    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. 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


    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

  2. The effects of beta acids from hops (Humulus lupulus) on mortality of Varroa destructor (Acari: Varroidae). (United States)

    Degrandi-Hoffman, Gloria; Ahumada, Fabiana; Probasco, Gene; Schantz, Lloyd


    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.

  3. 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.


    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

  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.M.; Doornbos, R.P.; Witkamp, R.F.; Greef, J. van der; Rodenburg, R.J.T.


    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

  5. 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;


    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...

  6. Pre-clinical properties of the alpha 4 beta 2 nicotinic acetylcholine receptor partial agonists varenicline, cytisine and dianicline translate to clinical efficacy for nicotine dependence

    NARCIS (Netherlands)

    Rollema, H.; Shrikhande, A.; Ward, K. M.; Tingley, F. D.; Coe, J. W.; O'Neill, B. T.; Tseng, E.; Wang, E. Q.; Mather, R. J.; Hurst, R. S.; Williams, K. E.; de Vries, M.; Cremers, T.; Bertrand, S.; Bertrand, D.


    Background and purpose: Smoking cessation trials with three high-affinity partial agonists of alpha 4 beta 2 neuronal nicotinic acetylcholine receptors (nAChRs) have demonstrated differences in their clinical efficacy. This work examines the origin of the differences by taking into account brain exp

  7. 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


    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

  8. 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


    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

  9. 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;


    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....

  10. Androgen receptors and hormone sensitivity of a human prostatic cancer cell line (PC-3) are modulated by natural beta-interferon

    NARCIS (Netherlands)

    G. Sica (G.); G. Dell'Acqua (G.); F. Iacopino (F.); A. Fattorossi (A.); P. Marchetti (P.); Th.H. van der Kwast (Theo); M. Pavone-Macaluso (M.)


    textabstractAndrogen recptors are expressed at a low level in the cell line PC-3, which does not respond to either androgens or antiandrogens. If these cells are exposed to natural beta-interferon (β-IFN) a reduction in cell growth and an increase in androgen receptors, evaluated by both biochemical

  11. 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


    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.

  12. 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


    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.

  13. Molecular identification of high and low affinity receptors for nicotinic acid. (United States)

    Wise, Alan; Foord, Steven M; Fraser, Neil J; Barnes, Ashley A; Elshourbagy, Nabil; Eilert, Michelle; Ignar, Diane M; Murdock, Paul R; Steplewski, Klaudia; Green, Andrew; Brown, Andrew J; Dowell, Simon J; Szekeres, Philip G; Hassall, David G; Marshall, Fiona H; Wilson, Shelagh; Pike, Nicholas B


    Nicotinic acid has been used clinically for over 40 years in the treatment of dyslipidemia producing a desirable normalization of a range of cardiovascular risk factors, including a marked elevation of high density lipoprotein and a reduction in mortality. The precise mechanism of action of nicotinic acid is unknown, although it is believed that activation of a G(i)-G protein-coupled receptor may contribute. Utilizing available information on the tissue distribution of nicotinic acid receptors, we identified candidate orphan receptors. The selected orphan receptors were screened for responses to nicotinic acid, in an assay for activation of G(i)-G proteins. Here we describe the identification of the G protein-coupled receptor HM74 as a low affinity receptor for nicotinic acid. We then describe the subsequent identification of HM74A in follow-up bioinformatics searches and demonstrate that it acts as a high affinity receptor for nicotinic acid and other compounds with related pharmacology. The discovery of HM74A as a molecular target for nicotinic acid may facilitate the discovery of superior drug molecules to treat dyslipidemia.

  14. Effect of beta-muricholic acid on the prevention and dissolution of cholesterol gallstones in C57L/J mice. (United States)

    Wang, David Q-H; Tazuma, Susumu


    This study investigated whether beta-muricholic acid, a natural trihydroxy hydrophilic bile acid of rodents, acts as a biliary cholesterol-desaturating agent to prevent cholesterol gallstones and if it facilitates the dissolution of gallstones compared with ursodeoxycholic acid (UDCA). For gallstone prevention study, gallstone-susceptible male C57L mice were fed 8 weeks with a lithogenic diet (2% cholesterol and 0.5% cholic acid) with or without 0.5% UDCA or beta-muricholic acid. For gallstone dissolution study, additional groups of mice that have formed gallstones were fed chow with or without 0.5% beta-muricholic acid or UDCA for 8 weeks. One hundred percent of mice fed the lithogenic diet formed cholesterol gallstones. Addition of beta-muricholic acid and UDCA decreased gallstone prevalence to 20% and 50% through significantly reducing biliary secretion rate, saturation index, and intestinal absorption of cholesterol, as well as inducing phase boundary shift and an enlarged Region E that prevented the transition of cholesterol from its liquid crystalline phase to solid crystals and stones. Eight weeks of beta-muricholic acid and UDCA administration produced complete gallstone dissolution rates of 100% and 60% compared with the chow (10%). We conclude that beta-muricholic acid is more effective than UDCA in treating or preventing diet-induced or experimental cholesterol gallstones in mice.

  15. 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: [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)


    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

  16. Altered food consumption in mice lacking lysophosphatidic acid receptor-1. (United States)

    Dusaulcy, R; Daviaud, D; Pradère, J P; Grès, S; Valet, Ph; Saulnier-Blache, J S


    The release of lysophosphatidic acid (LPA) by adipocytes has previously been proposed to play a role in obesity and associated pathologies such as insulin resistance and diabetes. In the present work, the sensitivity to diet-induced obesity was studied in mice lacking one of the LPA receptor subtype (LPA1R). Conversely to what was observed in wild type (WT) mice, LPA1R-KO-mice fed a high fat diet (HFD) showed no significant increase in body weight or fat mass when compared to low fat diet (LFD). In addition, in contrast to what was observed in WT mice, LPA1R-KO mice did not exhibit over-consumption of food associated with HFD. Surprisingly, when fed a LFD, LPA1R-KO mice exhibited significant higher plasma leptin concentration and higher level of adipocyte leptin mRNA than WT mice. In conclusion, LPA1R-KO mice were found to be resistant to diet-induced obesity consecutive to a resistance to fat-induced over-consumption of food that may result at least in part from alterations in leptin expression and production.

  17. Structural basis and functions of abscisic acid receptors PYLs (United States)

    Zhang, Xing L.; Jiang, Lun; Xin, Qi; Liu, Yang; Tan, Jian X.; Chen, Zhong Z.


    Abscisic acid (ABA) plays a key role in many developmental processes and responses to adaptive stresses in plants. Recently, a new family of nucleocytoplasmic PYR/PYL/RCAR (PYLs) has been identified as bona fide ABA receptors. PYLs together with protein phosphatases type-2C (PP2Cs), Snf1 (Sucrose-non-fermentation 1)-related kinases subfamily 2 (SnRK2s) and downstream substrates constitute the core ABA signaling network. Generally, PP2Cs inactivate SnRK2s kinases by physical interaction and direct dephosphorylation. Upon ABA binding, PYLs change their conformations and then contact and inhibit PP2Cs, thus activating SnRK2s. Here, we reviewed the recent progress in research regarding the structures of the core signaling pathways of ABA, including the (+)-ABA, (−)-ABA and ABA analogs pyrabactin as well as 6AS perception by PYLs, SnRK2s mimicking PYLs in binding PP2Cs. PYLs inhibited PP2Cs in both the presence and absence of ABA and activated SnRK2s. The present review elucidates multiple ABA signal perception and transduction by PYLs, which might shed light on how to design small chemical compounds for improving plant performance in the future. PMID:25745428

  18. The anticonvulsant gabapentin (neurontin) does not act through gamma-aminobutyric acid-B receptors

    DEFF Research Database (Denmark)

    Jensen, Anders A.; Mosbacher, Johannes; Elg, Susanne;


    The actions of the anticonvulsant gabapentin [1-(aminomethyl)cyclohexaneacetic acid, Neurontin] have been somewhat enigmatic until recently, when it was claimed to be a gamma-aminobutyric acid-B (GABA(B)) receptor agonist acting exclusively at a heterodimeric complex containing the GABA(B(1a...... in vitro assays. In light of these results, we find it highly questionable that gabapentin is a GABA(B) receptor agonist. Hence, the anticonvulsive effects of the compound have to arise from GABA(B) receptor-independent mechanisms. This also implies that the first GABA(B) receptor splice variant...

  19. Effects of gamma-aminobutyric acid receptors on muscarinic receptor-mediated free calcium ion levels in the facial nucleus following facial nerve injury

    Institute of Scientific and Technical Information of China (English)

    Guangfeng Jiang; Dawei Sun; Rui Zhou; Fugao Zhu; Yanqing Wang; Xiuming Wan; Banghua Liu


    Muscarinic receptors and nicotine receptors can increase free calcium ion levels in the facial nucleus via different channels following facial nerve injury. In addition, γ-aminobutyric acid A (GABAA) receptors have been shown to negatively regulate free calcium ion levels in the facial nucleus by inhibiting nicotine receptors. The present study investigated the influence of GABAA, γ-aminobutyric acid B (GABAB) and C (GABAC) receptors on muscarinic receptors in rats with facial nerve injury by confocal laser microscopy. GABAA and GABAB receptors exhibited significant dose-dependent inhibitory effects on increased muscarinic receptor-mediated free calcium ion levels following facial nerve injury. Results showed that GABAA and GABAB receptors negatively regulate muscarinic receptor effects and interplay with cholinergic receptors to regulate free calcium ion levels for facial neural regeneration.

  20. The fatty acid beta-oxidation pathway is important for decidualization of endometrial stromal cells in both humans and mice. (United States)

    Tsai, Jui-He; Chi, Maggie M-Y; Schulte, Maureen B; Moley, Kelle H


    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.

  1. Adenylyl cyclase type 6 overexpression selectively enhances beta-adrenergic and prostacyclin receptor-mediated inhibition of cardiac fibroblast function because of colocalization in lipid rafts. (United States)

    Liu, Xiaoqiu; Thangavel, Muthusamy; Sun, Shu Qiang; Kaminsky, Joseph; Mahautmr, Penden; Stitham, Jeremiah; Hwa, John; Ostrom, Rennolds S


    Cardiac fibroblasts produce and degrade extracellular matrix and are critical in regulating cardiac remodeling and hypertrophy. Fibroblasts are activated by factors such as transforming growth factor beta and inhibited by agents that elevate 3',5'-cyclic adenosine monophosphate (cAMP) levels. cAMP signal generation and response is known to be compartmentalized in many cell types in part through the colocalization of receptors and specific adenylyl cyclase isoforms in lipid rafts and caveolae. The present study sought to define the localization of key G protein-coupled receptors with adenylyl cyclase type 6 (AC6) in lipid rafts of rat cardiac fibroblasts and to determine if this colocalization was functionally relevant. We found that cardiac fibroblasts produce cAMP in response to agonists for beta-adrenergic (isoproterenol), prostaglandin EP2 (butaprost), adenosine (adenosine-5'-N-ethylcarboxamide, NECA), and prostacyclin (beraprost) receptors. Overexpression of AC6 increased cAMP production stimulated by isoproterenol and beraprost but not by butaprost or NECA. A key function of fibroblasts is the production of collagen. Isoproterenol- and beraprostmediated inhibition of collagen synthesis was also enhanced by AC6 overexpression, while inhibition by butaprost and NECA were unaltered. Lipid raft fractions from cardiac fibroblasts contain the preponderance of beta-adrenergic receptors and AC6 but exclude EP2 receptors. While we could not determine the localization of native prostacyclin receptors, we were able to determine that epitope-tagged prostanoid IP receptors (IPR) expressed in COS7 cells did localize, in part, in lipid raft fractions. These findings indicate that IP receptors are expressed in lipid rafts and can activate raft-localized AC isoforms. AC6 is completely compartmentized in lipid raft domains where it is activated solely by coresident G protein-coupled receptors to regulate cardiac fibroblast function.

  2. Normotensive sodium loading in normal man: Regulation of renin secretion during beta-receptor blockade

    DEFF Research Database (Denmark)

    Mølstrøm, Simon; Larsen, Nils Heden; Simonsen, Jane Angel;


    and renal excretion during slow saline loading at constant plasma sodium con-centration (Na-loading: 12 micromol Na(+) kg(-1) min(-1) for 4 h). Normal subjects were studied on low-sodium intake with and without beta1-adrenergic blockade by metoprolol. Metoprolol per se reduced RAAS activity as expected. Na......-loading decreased plasma renin (PRC) by 1/3, AngII by 1/2, and aldosterone (pAldo) by 2/3, (all pmetoprolol administration. Concomitantly, sodium excretion increased indistinguishably with and without metoprolol (16+/-2 to 71...

  3. 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)


    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)

  4. In utero Exposure to beta-2-Adrenergic Receptor Agonist Drugs and Risk for Autism Spectrum Disorders

    DEFF Research Database (Denmark)

    Gidaya, Nicole B.; Lee, Brian K.; Burstyn, Igor


    OBJECTIVES: The purpose of this study was to investigate associations between use of β-2-adrenergic receptor (B2AR) agonist drugs during pregnancy and risk for autism spectrum disorders (ASD). METHODS: A case-control study was conducted by using Denmark’s health and population registers. Among...

  5. 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


    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...

  6. Vagus Nerve Activity Augments Intestinal Macrophage Phagocytosis via Nicotinic Acetylcholine Receptor alpha 4 beta 2

    NARCIS (Netherlands)

    van der Zanden, Esmerij P.; Snoek, Susanne A.; Heinsbroek, Sigrid E.; Stanisor, Oana I.; Verseijden, Caroline; Boeckxstaens, Guy E.; Peppelenbosch, Maikel P.; Greaves, David R.; Gordon, Siamon; de Jonge, Wouter J.


    BACKGROUND & AIMS: The vagus nerve negatively regulates macrophage cytokine production via the release of acetylcholine (ACh) and activation of nicotinic acetylcholine receptors (nAChR). In various models of intestinal inflammation, vagus nerve efferent stimulation ameliorates disease. Given the act

  7. Inhibition of neointima formation by local delivery of estrogen receptor alpha and beta specific agonists

    NARCIS (Netherlands)

    Krom, Y.D.; Pires, N.M.M.; Jukema, J.W.; Vries, M.R. de; Frants, R.R.; Havekes, L.M.; Dijk, K.W. van; Quax, P.H.A.


    Objective: Neointima formation is the underlying mechanism of (in-stent) restenosis. 17β-Estradiol (E2) is known to inhibit injury-induced neointima formation and post-angioplasty restenosis. Estrogen receptor alpha (ERα) has been demonstrated to mediate E2 anti-restenotic properties. However, the r

  8. Evidence for the presence of both peroxisome proliferator-activated receptors alpha and beta in the rat spinal cord. (United States)

    Benani, A; Krémarik-Bouillaud, P; Bianchi, A; Netter, P; Minn, A; Dauça, M


    Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors belonging to the nuclear receptor superfamily. Different subtypes of PPARs (alpha, beta, and gamma) have been described. Their distinct physiological functions depend on their differential ligand activation profiles but also on their specific tissue expression. Previous studies have described their presence in the central nervous system. However, their expression in the adult rat spinal cord in normal physiological conditions has never been investigated. We demonstrated by using reverse-transcription-polymerase chain reaction, and Western blotting, the mRNA and protein expression of PPARalpha and PPARbeta, but not PPARgamma in cervical, thoracic, and lumbar segments of the spinal cord. Using immunohistochemistry, we also showed for the first time the specific cellular distribution of these transcription factors in the different segments of the spinal cord. In the gray matter, the distribution of PPARalpha was homogenous whereas PPARbeta was specifically localized in motoneurons and in medial part of laminae IV, V, VI, VII, VIII, and X. These latter areas are known as nociceptive afferent pathways to supra-spinal structures such as the medulla reticular nucleus and the thalamus. In the white matter, PPARalpha was localized exclusively in astrocytes while PPARbeta was present in oligodendrocytes. The possible functions of PPARalpha and PPARbeta expressed in both white and gray matters of the spinal cord will be discussed but need further studies.

  9. 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;


    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...

  10. DSD-1-Proteoglycan/Phosphacan and receptor protein tyrosine phosphatase-beta isoforms during development and regeneration of neural tissues. (United States)

    Faissner, Andreas; Heck, Nicolas; Dobbertin, Alexandre; Garwood, Jeremy


    Interactions between neurons and glial cells play important roles in regulating key events of development and regeneration of the CNS. Thus, migrating neurons are partly guided by radial glia to their target, and glial scaffolds direct the growth and directional choice of advancing axons, e.g., at the midline. In the adult, reactive astrocytes and myelin components play a pivotal role in the inhibition of regeneration. The past years have shown that astrocytic functions are mediated on the molecular level by extracellular matrix components, which include various glycoproteins and proteoglycans. One important, developmentally regulated chondroitin sulfate proteoglycan is DSD-1-PG/phosphacan, a glial derived proteoglycan which represents a splice variant of the receptor protein tyrosine phosphatase (RPTP)-beta (also known as PTP-zeta). Current evidence suggests that this proteoglycan influences axon growth in development and regeneration, displaying inhibitory or stimulatory effects dependent on the mode of presentation, and the neuronal lineage. These effects seem to be mediated by neuronal receptors of the Ig-CAM superfamily.

  11. 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


    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.

  12. Fluorescence histochemical study of the localisation and distribution of beta-adrenergic receptor sites in the spinal cord and cerebellum of the chicken. (United States)

    Bondok, A A; Botros, K G; el-Mohandes, E A


    The distribution of beta-adrenergic receptor sites has been studied in chicken spinal cord and cerebellum using a fluorescent analogue of propranolol, 9-amino-acridin-propranolol (9-AAP). In the cervical and lumbar regions of the spinal cord, beta-adrenoceptor sites were concentrated on cell bodies of alpha-motor neurons of the dorsolateral and ventrolateral nuclear groups of the ventral horn. In the thoracic region, they were present on cell bodies of the preganglionic sympathetic nucleus (dorsal commissural nucleus). In the dorsal horn, the receptor sites were present mainly on cell bodies of columna dorsalis magnocellularis. Sparse distribution of fluorescence was present in other regions of the gray matter. In the cerebellum, a dense distribution of beta-adrenergic receptor sites was observed on Purkinje cell bodies and their apical dendrites. Sparse distribution of receptor sites was present on fine ramifications of Purkinje cell dendrites in the molecular layer. Receptor sites were absent in the granule cell layer and the white matter. These observations indicate that alpha-motor neurons, preganglionic sympathetic neurons, neurons of columna dorsalis magnocellularis, and Purkinje cells are adrenoceptive, while granule cells are non-adrenoceptive.

  13. 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


    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.

  14. 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))


    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 of amiodarone hydrochloride 1 hr before the administration of (U-14C)palmitic acid. One hour after 100, 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 of amiodarone hydrochloride, but was still inhibited by 71 and 37%, 24 and 48 hr after 600 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.

  15. Elevated systemic glutamic acid level in the non-obese diabetic mouse is Idd linked and induces beta cell apoptosis. (United States)

    Banday, Viqar Showkat; Lejon, Kristina


    Although type 1 diabetes (T1D) is a T-cell-mediated disease in the effector stage, the mechanism behind the initial beta cell assault is less understood. Metabolomic differences, including elevated levels of glutamic acid, have been observed in patients with T1D before disease onset, as well as in pre-diabetic non-obese diabetic (NOD) mice. Increased levels of glutamic acid damage both neurons and beta cells, implying that this could contribute to the initial events of T1D pathogenesis. We investigated the underlying genetic factors and consequences of the increased levels of glutamic acid in NOD mice. Serum glutamic acid levels from a (NOD×B6)F2 cohort (n = 182) were measured. By genome-wide and Idd region targeted microsatellite mapping, genetic association was detected for six regions including Idd2, Idd4 and Idd22. In silico analysis of potential enzymes and transporters located in and around the mapped regions that are involved in glutamic acid metabolism consisted of alanine aminotransferase, glutamic-oxaloacetic transaminase, aldehyde dehydrogenase 18 family, alutamyl-prolyl-tRNA synthetase, glutamic acid transporters GLAST and EAAC1. Increased EAAC1 protein expression was observed in lysates from livers of NOD mice compared with B6 mice. Functional consequence of the elevated glutamic acid level in NOD mice was tested by culturing NOD. Rag2(-/-) Langerhans' islets with glutamic acid. Induction of apoptosis of the islets was detected upon glutamic acid challenge using TUNEL assay. Our results support the notion that a dysregulated metabolome could contribute to the initiation of T1D. We suggest that targeting of the increased glutamic acid in pre-diabetic patients could be used as a potential therapy.

  16. Receptor subtype-dependent positive and negative modulation of GABA(A) receptor function by niflumic acid, a nonsteroidal anti-inflammatory drug. (United States)

    Sinkkonen, Saku T; Mansikkamäki, Salla; Möykkynen, Tommi; Lüddens, Hartmut; Uusi-Oukari, Mikko; Korpi, Esa R


    In addition to blocking cyclooxygenases, members of the fenamate group of nonsteroidal anti-inflammatory drugs have been proposed to affect brain GABAA receptors. Using quantitative autoradiography with GABAA receptor-associated ionophore ligand [35S]t-butylbicyclophosphorothionate (TBPS) on rat brain sections, one of the fenamates, niflumate, at micromolar concentration was found to potentiate GABA actions in most brain areas, whereas being in the cerebellar granule cell layer an efficient antagonist similar to furosemide. With recombinant GABAA receptors expressed in Xenopus laevis oocytes, we found that niflumate potentiated 3 microM GABA responses up to 160% and shifted the GABA concentration-response curve to the left in alpha1beta2gamma2 receptors, the predominant GABAA receptor subtype in the brain. This effect needed the gamma2 subunit, because on alpha1beta2 receptors, niflumate exhibited solely an antagonistic effect at high concentrations. The potentiation was not abolished by the specific benzodiazepine site antagonist flumazenil. Niflumate acted as a potent antagonist of alpha6beta2 receptors (with or without gamma2 subunit) and of alphaXbeta2gamma2 receptors containing a chimeric alpha1 to alpha6 subunit, which suggests that niflumate antagonism is dependent on the same transmembrane domain 1- and 2-including fragment of the alpha6 subunit as furosemide antagonism. This antagonism was noncompetitive because the maximal GABA response, but not the potency, was reduced by niflumate. These data show receptor subtype-dependent positive and negative modulatory actions of niflumate on GABAA receptors at clinically relevant concentrations, and they suggest the existence of a novel positive modulatory site on alpha1beta2gamma2 receptors that is dependent on the gamma2 subunit but not associated with the benzodiazepine binding site.

  17. A subset of human pancreatic beta cells express functional CD14 receptors: a signaling pathway for beta cell-related glycolipids, sulfatide and ß-galactosylceramide

    DEFF Research Database (Denmark)

    Østerbye, Thomas; Funda, David P; Fundová, Petra;


    T1DM is a T-cell-mediated autoimmune disease targeting insulin-producing beta-cells. Multiple factors may contribute to the development of T1DM. Among these, the metabolic state of beta-cells and pro-inflammatory cytokines, produced by infiltrating immune cells, have been implicated in the precip...

  18. 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. (United States)

    Vicent, G P; Pecci, A; Ghini, A A; Piwien-Pilipuk, G; Veleiro, A S; Burton, G; Lantos, C P; Galigniana, M D


    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

  19. Structure of the activation domain of the GM-CSF/IL-3/IL-5 receptor common beta-chain bound to an antagonist. (United States)

    Rossjohn, J; McKinstry, W J; Woodcock, J M; McClure, B J; Hercus, T R; Parker, M W; Lopez, A F; Bagley, C J


    Heterodimeric cytokine receptors generally consist of a major cytokine-binding subunit and a signaling subunit. The latter can transduce signals by more than 1 cytokine, as exemplified by the granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-2 (IL-2), and IL-6 receptor systems. However, often the signaling subunits in isolation are unable to bind cytokines, a fact that has made it more difficult to obtain structural definition of their ligand-binding sites. This report details the crystal structure of the ligand-binding domain of the GM-CSF/IL-3/IL-5 receptor beta-chain (beta(c)) signaling subunit in complex with the Fab fragment of the antagonistic monoclonal antibody, BION-1. This is the first single antagonist of all 3 known eosinophil-producing cytokines, and it is therefore capable of regulating eosinophil-related diseases such as asthma. The structure reveals a fibronectin type III domain, and the antagonist-binding site involves major contributions from the loop between the B and C strands and overlaps the cytokine-binding site. Furthermore, tyrosine(421) (Tyr(421)), a key residue involved in receptor activation, lies in the neighboring loop between the F and G strands, although it is not immediately adjacent to the cytokine-binding residues in the B-C loop. Interestingly, functional experiments using receptors mutated across these loops demonstrate that they are cooperatively involved in full receptor activation. The experiments, however, reveal subtle differences between the B-C loop and Tyr(421), which is suggestive of distinct functional roles. The elucidation of the structure of the ligand-binding domain of beta(c) also suggests how different cytokines recognize a single receptor subunit, which may have implications for homologous receptor systems. (Blood. 2000;95:2491-2498)

  20. 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.

  1. 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: [Centro de Investigacao em Quimica (CIQ-UP), Faculdade de Ciencias da Universidade do Porto, Rua do Campo Alegre 687, 169-007 Porto (Portugal)


    {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.

  2. Receptor Density Is Key to the Alpha2/Beta Interferon Differential Activities


    Moraga, I.; Harari, D.; Schreiber, G.; Uze, G.; Pellegrini, S.


    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...

  3. Prediction of selective estrogen receptor beta agonist using open data and machine learning approach


    Niu,Ai-qin; Xie, Liang-jun; Wang, Hui; Bing ZHU; Wang, Sheng-Qi


    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...

  4. Salvianolic acid B, an antioxidant from Salvia miltiorrhiza, prevents A beta(25-35)-induced reduction in BPRP in PC12 cells

    NARCIS (Netherlands)

    Lin, Yan-Hua; Liu, Ai-Hua; Wu, Hong-Li; Westenbroek, Christel; Song, Qian-Liu; Yu, He-Ming; Ter Horst, Gert J.; Li, Xue-Jun; Li, Xiang-yi


    Several lines of evidence support that beta-amyloid (A beta)-induced neurotoxicity is mediated through the generation of reactive oxygen species (ROS) and elevation of intracellular calcium. Salvianolic acid B (Sal B), the major and most active anti-oxidant from Salvia miltiorrhiza. protects diverse

  5. 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


    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...... of work. No increase in lipolysis and no increase in ATBF were found when lipolysis was blocked by nicotinic acid (0.3 g/h). Propranolol treatment (0.15 mg/kg) reduced lipolysis and nearly abolished the increase in ATBF during exercise. Intravenous administration of glucose (about 0.25 g/min) did...

  6. Metabolism of fatty acid in yeast: characterisation of beta-oxidation and ultrastructural changes in the genus Sporidiobolus sp. cultivated on ricinoleic acid methyl ester. (United States)

    Feron, Gilles; Blin-Perrin, Caroline; Krasniewski, Isabelle; Mauvais, Geneviève; Lherminier, Jeannine


    Cell structure modifications and beta-oxidation induction were monitored in two strains of Sporidiobolus, Sp. Ruinenii and Sp. pararoseus after cultivation on ricinoleic acid methyl ester. Ultrastructural observations of the yeast before and after cultivation on fatty acid esters did not reveal major modifications in Sp. ruinenii. Unexpectedly, in Sp. pararoseus a proliferation of the mitochondrion was observed. After induction, Sp. ruinenii principally exhibited an increase in the activities of acyl-CoA oxidase (ACO), hydroxyacyl-CoA deshydrogenase (HAD), thiolase and catalase. In contrast, Sp. pararoseus lacked ACO and catalase activities, but an increase in acyl-CoA deshydrogenase (ACDH) and enoyl-CoA hydratase (ECH) activity was observed. These data suggest that in Sp. ruinenii, beta-oxidation is preferentially localized in the microbody, whereas in Sp. pararoseus it might be localized in the mitochondria.

  7. High-performance liquid chromatographic separation of carminic acid, alpha- and beta-bixin, and alpha- and beta-norbixin, and the determination of carminic acid in foods. (United States)

    Lancaster, F E; Lawrence, J F


    During a study of natural food colours, a simple and reliable high-performance liquid chromatography system was developed for use with cochineal and annato. An isocratic mobile phase, consisting of methanol and 6% aqueous acetic acid, resolved bixin and norbixin, while a gradient system was used to separate carminic acid and the annato compounds. The carminic acid contents of cochineal extract, carmine and carmine hydrosoluble were determined using an isocratic mobile phase (40:60, v/v). The detection limit for carminic acid in the various products was approximately 100 ng/g. Carminic acid was determined quantitatively in fruit beverages, yogurt and candies. It was demonstrated that, because of decomposition, carminic acid was not suitable for use in candies when manufacturing temperatures above 100 degrees C were required. Most membrane filters are not suitable for use with cochineal solutions, but a cellulose membrane filter did not adsorb carminic acid and was used successfully to remove impurities from water-based cochineal products and food extracts containing carminic acid.

  8. Breakdown kinetics of C-hydroxymethyl beta-dicarbonyl derivatives of carbon acids: implications in the bioconversion rate of C-phosphoryloxymethyl prodrugs of carbon acids. (United States)

    Dhareshwar, Sundeep S; Stella, Valentino J


    The kinetics of conversion of C-hydroxymethyl derivatives of pharmaceutically relevant beta-dicarbonyl carbon acids of two series, pyrazolidin-3,5-diones and inden-1,3-diones, and a model carbon acid back to the respective carbon acids were studied as a function of pH at 25 degrees C and an ionic strength of 0.15 M. This is a somewhat surprising reaction since it involves the facile breakdown of a carbon-carbon bond. The slopes of the pH-rate profiles for the dehydroxymethylation were approximately unity, which along with the lack of buffer catalysis, indicates a specific-base mechanism involving spontaneous breakdown of the oxymethyl anion. This breakdown generates the conjugate base of the respective carbon acids. Thus within a series, there exists a correlation between the second-order rate constant for dehydroxymethylation and the pK(a) of the corresponding carbon acid with a shorter conversion/dehydroxymethylation half-life (at all given pH values) with decreasing pK(a) of the parent carbon acid. The increasing acidity of the carbon acid affords an increase in the leaving group ability of the carbanion, and therefore facilitation of the rate-determining unimolecular carbon-carbon bond cleavage. Since the hydroxymethyl derivative is an intermediate in the bioconversion of C-phosphoryloxymethyl prodrugs of carbon acids, also under study, the relationship allows one to reasonably predict how facile the dehydroxymethylation would be for any new beta-dicarbonyl carbon acid.

  9. Control of Listeria monocytogenes on frankfurters by dipping in hops beta acids solutions. (United States)

    Shen, Cangliang; Geornaras, Ifigenia; Kendall, Patricia A; Sofos, John N


    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.

  10. Effect of hemolysis on nonesterified fatty acid and beta-hydroxybutyrate concentrations in bovine blood. (United States)

    Stokol, Tracy; Nydam, Daryl V


    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.

  11. Interaction of Beta-Hydroxy-Beta-Methylbutyrate Free Acid and Adenosine Triphosphate on Muscle Mass, Strength, and Power in Resistance Trained Individuals. (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


    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 jump and Wingate 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.

  12. Central beta-adrenergic receptors play an important role in the enhancing effect of voluntary exercise on learning and memory in rat. (United States)

    Ebrahimi, Shima; Rashidy-Pour, Ali; Vafaei, Abbas A; Akhavan, Maziar M


    The beneficial effects of physical activity and exercise on brain functions such as improvement in learning and memory are well documented. The aim of this study was to examine the role of the beta-adrenergic system in voluntary exercise-induced enhancement of learning and memory in rat. In order to block the b