11 results on '"Sarau HM"'
Search Results
2. The peptidic urotensin-II receptor ligand GSK248451 possesses less intrinsic activity than the low-efficacy partial agonists SB-710411 and urantide in native mammalian tissues and recombinant cell systems.
- Author
-
Behm DJ, Stankus G, Doe CP, Willette RN, Sarau HM, Foley JJ, Schmidt DB, Nuthulaganti P, Fornwald JA, Ames RS, Lambert DG, Calo' G, Camarda V, Aiyar NV, and Douglas SA
- Subjects
- Animals, Arteries drug effects, Arteries physiology, Binding, Competitive drug effects, Blood Pressure drug effects, Calcium metabolism, Cats, Cell Line, Dose-Response Relationship, Drug, Haplorhini, Humans, In Vitro Techniques, Male, Peptide Fragments metabolism, Peptides, Cyclic chemistry, Radioligand Assay, Rats, Rats, Sprague-Dawley, Receptors, G-Protein-Coupled genetics, Receptors, G-Protein-Coupled metabolism, Recombinant Proteins antagonists & inhibitors, Recombinant Proteins metabolism, Urotensins metabolism, Vasoconstriction drug effects, Vasoconstrictor Agents pharmacology, Peptide Fragments pharmacology, Peptides, Cyclic pharmacology, Receptors, G-Protein-Coupled antagonists & inhibitors, Urotensins pharmacology
- Abstract
Several peptidic urotensin-II (UT) receptor antagonists exert 'paradoxical' agonist activity in recombinant cell- and tissue-based bioassay systems, likely the result of differential urotensin-II receptor (UT receptor) signal transduction/coupling efficiency between assays. The present study has examined this phenomenon in mammalian arteries and recombinant UT-HEK (human embryonic kidney) cells.BacMam-mediated recombinant UT receptor upregulation in HEK cells augmented agonist activity for all four peptidic UT ligands studied. The nominal rank order of relative intrinsic efficacy was U-II>urantide ([Pen(5)-DTrp(7)-Orn(8)]hU-II(4-11))>SB-710411 (Cpa-c[DCys-Pal-DTrp-Lys-Val-Cys]-Cpa-amide)>>GSK248451 (Cin-c[DCys-Pal-DTrp-Orn-Val-Cys]-His-amide) (the relative coupling efficiency of recombinant HEK cells was cat>human>>rat UT receptor). The present study further demonstrated that the use of high signal transduction/coupling efficiency isolated blood vessel assays (primate>cat arteries) is required in order to characterize UT receptor antagonism thoroughly. This cannot be attained simply by using the rat isolated aorta, an artery with low signal transduction/coupling efficiency in which low-efficacy agonists appear to function as antagonists. In contrast to the 'low-efficacy agonists' urantide and SB-710411, GSK248451 functioned as a potent UT receptor antagonist in all native isolated tissues studied (UT receptor selectivity was confirmed in the rat aorta). Further, GSK248451 exhibited an extremely low level of relative intrinsic activity in recombinant HEK cells (4-5-fold less than seen with urantide). Since GSK248451 (1 mg kg(-1), i.v.) blocked the systemic pressor actions of exogenous U-II in the anaesthetized cat, it represents a suitable peptidic tool antagonist for delineating the role of U-II in the aetiology of mammalian cardiometabolic diseases.
- Published
- 2006
- Full Text
- View/download PDF
3. Aminoalkoxybenzyl pyrrolidines as novel human urotensin-II receptor antagonists.
- Author
-
Jin J, Dhanak D, Knight SD, Widdowson K, Aiyar N, Naselsky D, Sarau HM, Foley JJ, Schmidt DB, Bennett CD, Wang B, Warren GL, Moore ML, Keenan RM, Rivero RA, and Douglas SA
- Subjects
- Drug Evaluation, Preclinical, Humans, Pyrrolidines pharmacology, Stereoisomerism, Structure-Activity Relationship, Pyrrolidines chemical synthesis, Receptors, G-Protein-Coupled antagonists & inhibitors
- Abstract
High throughput screening of the corporate compound collection led to the discovery of a novel series of substituted aminoalkoxybenzyl pyrrolidines as human urotensin-II receptor antagonists. The synthesis, initial structure-activity relationships, and optimization of the initial hit that led to the identification of a truncated sub-series, represented by SB-436811 (1a), are described.
- Published
- 2005
- Full Text
- View/download PDF
4. Nonpeptidic urotensin-II receptor antagonists I: in vitro pharmacological characterization of SB-706375.
- Author
-
Douglas SA, Behm DJ, Aiyar NV, Naselsky D, Disa J, Brooks DP, Ohlstein EH, Gleason JG, Sarau HM, Foley JJ, Buckley PT, Schmidt DB, Wixted WE, Widdowson K, Riley G, Jin J, Gallagher TF, Schmidt SJ, Ridgers L, Christmann LT, Keenan RM, Knight SD, and Dhanak D
- Subjects
- Algorithms, Animals, Aorta, Thoracic drug effects, Binding, Competitive drug effects, Cats, Cell Line, Tumor, Cell Membrane metabolism, Haplorhini, Humans, In Vitro Techniques, Mice, Muscle Contraction drug effects, Muscle, Smooth, Vascular drug effects, Radioligand Assay, Rats, Recombinant Proteins metabolism, Rhabdomyosarcoma metabolism, Species Specificity, Pyrrolidines pharmacology, Receptors, G-Protein-Coupled antagonists & inhibitors, Receptors, G-Protein-Coupled genetics, Sulfonamides pharmacology
- Abstract
1. SB-706375 potently inhibited [(125)I]hU-II binding to both mammalian recombinant and 'native' UT receptors (K(i) 4.7+/-1.5 to 20.7+/-3.6 nM at rodent, feline and primate recombinant UT receptors and K(i) 5.4+/-0.4 nM at the endogenous UT receptor in SJRH30 cells). 2. Prior exposure to SB-706375 (1 microM, 30 min) did not alter [(125)I]hU-II binding affinity or density in recombinant cells (K(D) 3.1+/-0.4 vs 5.8+/-0.9 nM and B(max) 3.1+/-1.0 vs 2.8+/-0.8 pmol mg(-1)) consistent with a reversible mode of action. 3. The novel, nonpeptidic radioligand [(3)H]SB-657510, a close analogue of SB-706375, bound to the monkey UT receptor (K(D) 2.6+/-0.4 nM, B(max) 0.86+/-0.12 pmol mg(-1)) in a manner that was inhibited by both U-II isopeptides and SB-706375 (K(i) 4.6+/-1.4 to 17.6+/-5.4 nM) consistent with the sulphonamides and native U-II ligands sharing a common UT receptor binding domain. 4. SB-706375 was a potent, competitive hU-II antagonist across species with pK(b) 7.29-8.00 in HEK293-UT receptor cells (inhibition of [Ca(2+)](i)-mobilization) and pK(b) 7.47 in rat isolated aorta (inhibition of contraction). SB-706375 also reversed tone established in the rat aorta by prior exposure to hU-II (K(app) approximately 20 nM). 5. SB-706375 was a selective U-II antagonist with >/=100-fold selectivity for the human UT receptor compared to 86 distinct receptors, ion channels, enzymes, transporters and nuclear hormones (K(i)/IC(50)>1 microM). Accordingly, the contractile responses induced in isolated aortae by KCl, phenylephrine, angiotensin II and endothelin-1 were unaltered by SB-706375 (1 microM). 6. In summary, SB-706375 is a high-affinity, surmountable, reversible and selective nonpeptide UT receptor antagonist with cross-species activity that will assist in delineating the pathophysiological actions of U-II in mammals.
- Published
- 2005
- Full Text
- View/download PDF
5. Cloning and pharmacological characterization of the cat urotensin-II receptor (UT).
- Author
-
Aiyar N, Johns DG, Ao Z, Disa J, Behm DJ, Foley JJ, Buckley PT, Sarau HM, van-der-Keyl HK, Elshourbagy NA, and Douglas SA
- Subjects
- Amino Acid Sequence, Animals, Calcium Signaling physiology, Cats, Cell Line, Cell Membrane physiology, Conserved Sequence, DNA Primers, Humans, Inositol Phosphates metabolism, Mice, Molecular Sequence Data, Organ Specificity, Polymerase Chain Reaction, RNA, Messenger genetics, Rats, Receptors, G-Protein-Coupled drug effects, Receptors, G-Protein-Coupled metabolism, Recombinant Proteins drug effects, Recombinant Proteins metabolism, Sequence Alignment, Sequence Homology, Amino Acid, Transfection, Cloning, Molecular, Receptors, G-Protein-Coupled genetics
- Abstract
Urotensin-II (U-II), acting through its G-protein-coupled receptor, UT, is a possible contributor to hypertension. Variable functional responses to U-II, both within and between species studied to date, complicate the characterization of UT antagonists. In the cat, however, U-II causes systemic hypertension and constricts arterial segments isolated from several vascular beds. The purpose of this study was to clone and pharmacologically characterize cat recombinant UT to determine whether this system represents a model for characterizing UT antagonists. Cloned cat UT displayed 74% identity to primate UT, and 77% identity to rodent UT. [(125)I] hU-II bound in a saturable manner to a single site on recombinant cat UT with high affinity (K(D) 288+/-13pM) and high density (B(max) 747+/-66fmol/mg protein). U-II isopeptides displayed equipotent, high affinity binding to cat UT (K(i) 1.8-5.3nM). Cat UT was coupled to intracellular [Ca(2+)] release (EC(50) 0.6+/-0.2nM) and total inositol phosphate (IP) formation (EC(50) 0.4+/-0.1nM). Protein kinase C activation desensitized cat, but not human, UT-mediated IP formation. UT mRNA expression was detected in cat blood vessels, trachea, lung, and kidney, where the medulla (K(D) 815+/-34) and cortex and (K(D) 316+/-39pM) displayed high affinity binding for human U-II (hU-II). The cat urotensin-II receptor represents a suitable in vitro model to examine the role of the U-II/UT system in the etiology of hypertension, assisting in the evaluation of the UT antagonists to help treat cardiovascular disease.
- Published
- 2005
- Full Text
- View/download PDF
6. The neuromedin B receptor antagonist, BIM-23127, is a potent antagonist at human and rat urotensin-II receptors.
- Author
-
Herold CL, Behm DJ, Buckley PT, Foley JJ, Wixted WE, Sarau HM, and Douglas SA
- Subjects
- Animals, Aorta, Thoracic drug effects, Binding, Competitive, Calcium metabolism, Cell Line, Dose-Response Relationship, Drug, Humans, In Vitro Techniques, Male, Rats, Rats, Sprague-Dawley, Urotensins pharmacology, Peptides, Cyclic pharmacology, Receptors, Bombesin antagonists & inhibitors, Receptors, G-Protein-Coupled antagonists & inhibitors
- Abstract
The functional activity of the peptidic neuromedin B receptor antagonist BIM-23127 was investigated at recombinant and native urotensin-II receptors (UT receptors). Human urotensin-II (hU-II) promoted intracellular calcium mobilization in HEK293 cells expressing the human UT (hUT) or rat UT (rUT) receptors with pEC(50) values of 9.80+/-0.34 (n=6) and 9.06+/-0.32 (n=4), respectively. While BIM-23127 alone had no effect on calcium responses in either cell line, it was a potent and competitive antagonist at both hUT (pA(2)=7.54+/-0.14; n=3) and rUT (pA(2)=7.70+/-0.05; n=3) receptors. Furthermore, BIM-23127 reversed hU-II-induced contractile tone in the rat-isolated aorta with a pIC(50) of 6.66+/-0.04 (n=4). In conclusion, BIM- 23127 is the first hUT receptor antagonist identified to date and should not be considered as a selective neuromedin B receptor antagonist.
- Published
- 2003
- Full Text
- View/download PDF
7. Cloning, pharmacology, and tissue distribution of G-protein-coupled receptor GPR105 (KIAA0001) rodent orthologs.
- Author
-
Freeman K, Tsui P, Moore D, Emson PC, Vawter L, Naheed S, Lane P, Bawagan H, Herrity N, Murphy K, Sarau HM, Ames RS, Wilson S, Livi GP, and Chambers JK
- Subjects
- Amino Acid Sequence, Animals, Base Sequence, Blotting, Southern, Cloning, Molecular, Humans, Mice, Molecular Sequence Data, Open Reading Frames, Rats, Receptors, Cell Surface agonists, Receptors, Cell Surface chemistry, Receptors, Cell Surface metabolism, Receptors, Purinergic P2Y, Sequence Homology, Amino Acid, Uridine Diphosphate Glucose pharmacology, GTP-Binding Proteins metabolism, Receptors, Cell Surface genetics, Receptors, G-Protein-Coupled, Receptors, Purinergic P2
- Abstract
It has recently been shown that UDP-glucose is a potent agonist of the orphan G-protein-coupled receptor (GPCR) KIAA0001. Here we report cloning and analysis of the rat and mouse orthologs of this receptor. In accordance with GPCR nomenclature, we have renamed the cDNA clone, KIAA0001, and its orthologs GPR105 to reflect their functionality as G-protein-coupled receptors. The rat and mouse orthologs show 80% and 83% amino acid identity, respectively, to the human GPR105 protein. We demonstrate by genomic Southern blot analysis that there are no genes in the mouse or rat genomes with higher sequence similarity. Chromosomal mapping shows that the mouse and human genes are located on syntenic regions of chromosome 3. Further analyses of the rat and mouse GPR105 proteins show that they are activated by the same agonists as the human receptor, responding to UDP-glucose and closely related molecules with similar affinities. The mouse and rat receptors are widely expressed, as is the human receptor. Thus we conclude that we have identified the rat and mouse orthologs of the human gene GPR105.
- Published
- 2001
- Full Text
- View/download PDF
8. EDG1 receptor stimulation leads to cardiac hypertrophy in rat neonatal myocytes.
- Author
-
Robert P, Tsui P, Laville MP, Livi GP, Sarau HM, Bril A, and Berrebi-Bertrand I
- Subjects
- Adrenergic alpha-Agonists pharmacology, Animals, Animals, Newborn, Cardiomegaly chemically induced, Cardiomegaly metabolism, Cells, Cultured, Culture Media, Serum-Free, Dose-Response Relationship, Drug, Humans, Microscopy, Fluorescence, Mitogen-Activated Protein Kinases antagonists & inhibitors, Mitogen-Activated Protein Kinases metabolism, Myocardium cytology, Myocardium metabolism, Peptides immunology, Peptides metabolism, Phenylephrine pharmacology, Phosphatidylinositol 3-Kinases metabolism, Phosphoinositide-3 Kinase Inhibitors, Protein Structure, Tertiary, Rats, Rats, Wistar, Receptors, Cell Surface metabolism, Receptors, Lysophospholipid, Sphingosine chemistry, Sphingosine metabolism, Stress Fibers metabolism, Tissue Extracts chemistry, Virulence Factors, Bordetella pharmacology, Cardiomegaly pathology, Heart drug effects, Immediate-Early Proteins metabolism, Lysophospholipids, Receptors, G-Protein-Coupled, Sphingosine analogs & derivatives, Sphingosine pharmacology
- Abstract
Sphingosine 1 phosphate (S1P), an aminophospholipid, acts extracellularly as a ligand via the specific G protein-coupled receptors of the endothelial differentiation gene (EDG) 1, 3, 5, 6 and 8 receptors family and intracellularly as a second messenger in various cellular types. The aim of this work was to investigate biological activity of S1P in cardiomyocytes with respect to related sphingolipids. S1P was applied for 48 h on rat neonatal cardiomyocytes at 10 nM, 100 nM and 1 microM. S1P induced a concentration-dependent cellular hypertrophy evidenced by an increase in cell size, [3H]-phenylalanine incorporation, protein content and Brain Natriuretic Peptide (BNP) secretion. Among the lipids tested S1P exhibits the lower EC50 (67 nM) followed by dihydro-S1P (107 nM) and sphingosylphosphorylcholine (1.6 microM). The effect of S1P could be related to a stimulation of the EDG1 receptor since we showed that the EDG1 receptor is predominantly expressed at the mRNA and protein levels in rat cardiomyocytes and that specific anti-EDG1 antibodies inhibited the hypertrophic effect induced by S1P. Furthermore the expression level of most other EDG receptors for S1P appeared very low in cardiac myocytes. S1P (100 nM) increased the phosphorylation of p42/44MAPK, p38MAPK, JNK, Akt and p70(S6K), this effect being reversed by inhibitors of their respective phosphorylation which also rescue the hypertrophic phenotype. Finally, S1P stimulated actin stress fibre formation reverted by the Rho inhibitor, the C3 exoenzyme. Altogether, our results show that S1P induces cardiomyocyte hypertrophy mainly via the EDG1 receptor and subsequently via Gi through ERKs, p38 MAPK, JNK, PI3K and via Rho pathway., (Copyright 2001 Academic Press.)
- Published
- 2001
- Full Text
- View/download PDF
9. Identification of an EDG7 variant, HOFNH30, a G-protein-coupled receptor for lysophosphatidic acid.
- Author
-
Fitzgerald LR, Dytko GM, Sarau HM, Mannan IJ, Ellis C, Lane PA, Tan KB, Murdock PR, Wilson S, Bergsma DJ, Ames RS, Foley JJ, Campbell DA, McMillan L, Evans N, Elshourbagy NA, Minehart H, and Tsui P
- Subjects
- Amino Acid Sequence, Base Sequence, Calcium metabolism, Chromosome Mapping, Chromosomes, Human, Pair 1, Cloning, Molecular, Enzyme Activation, Humans, Jurkat Cells, Mitogen-Activated Protein Kinase 1 metabolism, Mitogen-Activated Protein Kinase 3, Mitogen-Activated Protein Kinases metabolism, Molecular Sequence Data, Phosphorylation, Receptors, Cell Surface chemistry, Receptors, Cell Surface metabolism, Receptors, Lysophosphatidic Acid, Sequence Homology, Amino Acid, Tumor Cells, Cultured, GTP-Binding Proteins metabolism, Lysophospholipids metabolism, Receptors, Cell Surface genetics, Receptors, G-Protein-Coupled
- Abstract
We have identified a cDNA, designated HOFNH30, which encodes a 354 amino acid G-protein-coupled receptor (GPCR). This receptor has 96% amino acid identity to the Jurkat-T cell-derived EDG7 and could be a splice variant. RT-PCR analysis demonstrated that HOFNH30 mRNA is expressed in placenta whereas EDG7 mRNA shows highest expression in prostate. The HOFNH30 gene is localized to human chromosome 1p22. 3-1p31.1. When HOFNH30 was expressed in RBL-2H3 cells, LPA and phosphatidic acid (PA) induced a calcium mobilization response with EC(50) values of 13 nM and 3 microM, respectively. LPA also induced phosphorylation of mitogen-activated protein kinase (p42(MAPK) and p44(MAPK)) in HOFNH30-transfected but not vector-transfected RBL-2H3 cells. In the present study, we have identified a novel variant from the EDG receptor family, a GPCR for which LPA is a high-affinity endogenous ligand., (Copyright 2000 Academic Press.)
- Published
- 2000
- Full Text
- View/download PDF
10. Human urotensin-II is a potent vasoconstrictor and agonist for the orphan receptor GPR14.
- Author
-
Ames RS, Sarau HM, Chambers JK, Willette RN, Aiyar NV, Romanic AM, Louden CS, Foley JJ, Sauermelch CF, Coatney RW, Ao Z, Disa J, Holmes SD, Stadel JM, Martin JD, Liu WS, Glover GI, Wilson S, McNulty DE, Ellis CE, Elshourbagy NA, Shabon U, Trill JJ, Hay DW, Ohlstein EH, Bergsma DJ, and Douglas SA
- Subjects
- Amino Acid Sequence, Animals, Base Sequence, Calcium metabolism, Cell Line, Cloning, Molecular, DNA, Complementary, GTP-Binding Proteins genetics, Humans, Macaca fascicularis, Male, Molecular Sequence Data, Rats, Rats, Sprague-Dawley, Receptors, Cell Surface genetics, Receptors, Cell Surface metabolism, Sequence Homology, Amino Acid, Tissue Distribution, Urotensins metabolism, Vasoconstrictor Agents metabolism, GTP-Binding Proteins agonists, GTP-Binding Proteins metabolism, Receptors, Cell Surface agonists, Receptors, G-Protein-Coupled, Urotensins pharmacology, Vasoconstrictor Agents pharmacology
- Abstract
Urotensin-II (U-II) is a vasoactive 'somatostatin-like' cyclic peptide which was originally isolated from fish spinal cords, and which has recently been cloned from man. Here we describe the identification of an orphan human G-protein-coupled receptor homologous to rat GPR14 and expressed predominantly in cardiovascular tissue, which functions as a U-II receptor. Goby and human U-II bind to recombinant human GPR14 with high affinity, and the binding is functionally coupled to calcium mobilization. Human U-II is found within both vascular and cardiac tissue (including coronary atheroma) and effectively constricts isolated arteries from non-human primates. The potency of vasoconstriction of U-II is an order of magnitude greater than that of endothelin-1, making human U-II the most potent mammalian vasoconstrictor identified so far. In vivo, human U-II markedly increases total peripheral resistance in anaesthetized non-human primates, a response associated with profound cardiac contractile dysfunction. Furthermore, as U-II immunoreactivity is also found within central nervous system and endocrine tissues, it may have additional activities.
- Published
- 1999
- Full Text
- View/download PDF
11. Platelet-activating factor-induced phosphoinositide metabolism in differentiated U-937 cells in culture.
- Author
-
Barzaghi G, Sarau HM, and Mong S
- Subjects
- GTP-Binding Proteins physiology, Humans, Leukemia, Myeloid metabolism, Pertussis Toxin, Receptors, Cell Surface physiology, Signal Transduction, Tumor Cells, Cultured, Virulence Factors, Bordetella pharmacology, Calcium metabolism, Phosphatidylinositols metabolism, Platelet Activating Factor pharmacology, Platelet Membrane Glycoproteins, Receptors, G-Protein-Coupled
- Abstract
Human monocytic leukemic U-937 cells, when differentiated with dimethylsulfoxide to macrophage-like state, express receptors for platelet-activating factor (PAF). In the differentiated U-937 cells, PAF induced hydrolysis of phosphoinositides and synthesis of inositol phosphates. PAF-induced production of inositol phosphates was rapid, concentration-dependent and was inhibited by a receptor antagonist CV3988, indicating that it was mediated via a specific receptor. In fura-2-loaded, differentiated U-937 cells, PAF induced immediate and concentration-dependent calcium mobilization [( Ca++]i) that was inhibited by CV3988, but not by calcium channel blockers. Addition of an increasing concentration of calcium chelator, ethylene glycol bis(beta-aminoethyl ether)-N,N'-tetraacetic acid, to the medium inhibited a large fraction (approximately 75%) of PAF receptor-induced [Ca++]i mobilization thus suggesting the majority of [Ca++]i mobilization was originated from extracellular milieu and a small portion (approximately 25%) was originated from intracellular sources. The inositol phosphate production induced by PAF, however, was independent from the extracellular calcium and was not inhibited by the addition of ethylene glycol bis(beta-aminoethyl ether)-N,N'-tetraacetic acid. Neither [Ca++]i mobilization or phosphoinositide metabolism in U-937 cells was sensitive to treatment of pertussis toxin, but both types of effects were sensitive to treatment by an inhibitor of phospholipase C, manoalide. These results suggest that in differentiated U-937 cells PAF receptor is coupled through a pertussis toxin-insensitive guanine nucleotide binding protein to a phosphoinositide specific phospholipase C. Inositol-trisphosphate, and possibly diacylglycerol, could be the intracellular messengers for PAF receptor in U-937 cells.
- Published
- 1989
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.