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* Context.--Although several neuroendocrine cell types constitute gastroenteropancreatic neuroendocrine tumors (NETs), the clinical and prognostic implications of the expression of multiple peptide hormones have not been comprehensively evaluated in rectal NETs. Objective.--To identify the clinicopathologic characteristics and prognostic impact of peptide hormone expression. Design.--We evaluated the expression of peptide YY (PYY), glucagon, somatostatin, serotonin, insulin, and gastrin using immunolabeling in 446 endoscopically or surgically resected rectal NETs. Results.--PYY, glucagon, serotonin, somatostatin, insulin, and gastrin were expressed in 261 of 389 (67.1%), 205 of 446 (46.0%), 36 of 446 (8.1%), 33 of 446 (7.4%), 2 of 446 (0.4%), and 1 of 446 cases (0.2%), respectively. Immunoreactivity to any peptide hormone was present in 345 of 446 cases (77.4%). Tumors expressing serotonin or somatostatin were associated with lymphovascular invasion, chromogranin A expression, and shorter disease-free survival (DFS). Rectal NETs were classified as L-cell, enterochromaffin-cell, D-cell, null-expression, or mixed-expression type based on peptide hormonal expression status. Patients with D-cell Net had the shortest DfS (10-year DFS, 54.5%), followed by those with enterochromaffin-cell NET (89.5%), null expression (97.0%), L-cell NET (99.6%), and mixed-expression NET (100%; P < .001). Multivariable analyses revealed that somatostatin expression was an independent indicator of poor prognosis with respect to DFS in rectal NETs (P = .001). Conclusions.--Somatostatin expression is a poor prognostic indicator in patients with rectal NETs. Therefore, additional peptide hormonal immunolabeling, including somatostatin, serotonin, and PYY, in rectal NETs can provide more information regarding DFS. (Arch Pathol Lab Med. 2023;147:797-807; doi: 10.5858/ arpa.2022-0032-OA), The incidence of gastroenteropancreatic (GEP) neuroendocrine tumors (NETs) has increased substantially during the past few decades. They are currently the second most common digestive system tumor, after colorectal cancer. (1,2) [...]

Class B G-protein-coupled receptors are major targets for the treatment of chronic diseases, including diabetes and obesity.sup.1. Structures of active receptors reveal peptide agonists engage deep within the receptor core, leading to an outward movement of extracellular loop 3 and the tops of transmembrane helices 6 and 7, an inward movement of transmembrane helix 1, reorganization of extracellular loop 2 and outward movement of the intracellular side of transmembrane helix 6, resulting in G-protein interaction and activation.sup.2-6. Here we solved the structure of a non-peptide agonist, TT-OAD2, bound to the glucagon-like peptide-1 (GLP-1) receptor. Our structure identified an unpredicted non-peptide agonist-binding pocket in which reorganization of extracellular loop 3 and transmembrane helices 6 and 7 manifests independently of direct ligand interaction within the deep transmembrane domain pocket. TT-OAD2 exhibits biased agonism, and kinetics of G-protein activation and signalling that are distinct from peptide agonists. Within the structure, TT-OAD2 protrudes beyond the receptor core to interact with the lipid or detergent, providing an explanation for the distinct activation kinetics that may contribute to the clinical efficacy of this compound series. This work alters our understanding of the events that drive the activation of class B receptors. The structure of GLP-1R and its G protein in complex with the small molecule TT-OAD2 sheds light on how the TT-OAD2 agonist can activate the receptor and provides insights into the development of therapeutic agents for metabolic disorders., Author(s): Peishen Zhao [sup.1] , Yi-Lynn Liang [sup.1] , Matthew J. Belousoff [sup.1] , Giuseppe Deganutti [sup.2] , Madeleine M. Fletcher [sup.1] , Francis S. Willard [sup.3] , Michael G. [...]

Ageing in multicellular organisms typically involves a progressive decline in cell replacement and repair processes, resulting in several physiological deficiencies, including inefficient muscle repair, reduced bone mass, and dysregulation of blood formation (haematopoiesis). Although defects in tissue-resident stem cells clearly contribute to these phenotypes, it is unclear to what extent they reflect stem cell intrinsic alterations or age-related changes in the stem cell supportive microenvironment, or niche. Here, using complementary in vivo and in vitro heterochronic models, we show that age-associated changes in stem cell supportive niche cells deregulate normal haematopoiesis by causing haematopoietic stem cell dysfunction. Furthermore, we find that age-dependent defects in niche cells are systemically regulated and can be reversed by exposure to a young circulation or by neutralization of the conserved longevity regulator, insulin-like growth factor-1, in the marrow microenvironment. Together, these results show a new and critical role for local and systemic factors in signalling age-related haematopoietic decline, and highlight a new model in which blood-borne factors in aged animals act through local niche cells to induce age-dependent disruption of stem cell function., Age-associated pathologies represent a significant and growing global health care concern, particularly as demographic trends predict a doubling in the number of individuals over 65 years of age in the [...]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2009.08.001 Byline: Michelle Myers (a), Brooke S. Middlebrook (a), Martin M. Matzuk (a)(b)(c), Stephanie A. Pangas (a) Keywords: Inhibin; Activin; Folliculogenesis; Oocyte; Follicle; Prepubertal mouse Abstract: Targeted disruption of the inhibin [alpha] gene (Inha.sup.- .sup./ .sup.-) in mice results in an ovarian phenotype of granulosa cell tumors that renders the animals infertile. Little is known about the reproductive defects prior to tumor development. Here, we report novel data on early follicle dynamics in Inha.sup.- .sup./ .sup.- mice, which demonstrate that inhibin [alpha] has important consequences upon follicle development. Morphological changes in both germ and somatic cells were evident in postnatal day 12 ovaries, with Inha.sup.-/- mice exhibiting numerous multilayered follicles that were far more advanced than those observed in age-matched controls. These changes were accompanied by alterations in follicle dynamics such that Inha.sup.-/- ovaries had fewer follicles in the resting pool and more committed in the growth phase. Absence of inhibin [alpha] resulted in advanced follicular maturation as marked by premature loss of anti-Mullerian hormone (AMH) in secondary follicles. Additionally, gene expression analysis revealed changes in factors known to be vital for oocyte and follicle development. Together, these data provide key evidence to suggest that regulation of the inhibin/activin system is essential for early folliculogenesis in the prepubertal mouse ovary. Author Affiliation: (a) Department of Pathology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA (b) Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA (c) Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA Article History: Received 29 May 2009; Revised 21 July 2009; Accepted 3 August 2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2009.07.022 Byline: Maite Rielland (a)(b), Vincent Brochard (a)(b), Marie-Christine Lacroix (c)(d), Jean-Paul Renard (a)(b), Alice Jouneau (a)(b) Keywords: Trophoblast; Nuclear transfer; Reprogramming; Self-renewal; Stem cells; Embryo; Growth factors Abstract: Development after nuclear transfer (NT) is subjected to defects originating from both the epiblast and the trophoblast parts of the conceptus and is always accompanied by placentomegaly at term. Here we have investigated the origin of the reprogramming errors affecting the trophoblast lineage in mouse NT embryos. We show that trophoblast stem (TS) cells can be derived from NT embryos (ntTS cells) and used as an experimental in vitro model of trophoblast proliferation and differentiation. Strikingly, TS derivation is more efficient from NT embryos than from controls and ntTS cells exhibit a growth advantage over control TS cells under self-renewal conditions. While epiblast-produced growth factors Fgf4 and Activin exert a fine-tuned control on the balance between self-renewal and differentiation of control TS cells, ntTS cells exhibit a reduced dependency upon their micro-environment. Since the supply of growth factors is known do decrease at the onset of placental formation in vivo we propose that TS cells in NT embryos continue to self-renew during a longer period of time than in fertilized embryo. The resulting increased pool of progenitors could contribute to the enlarged extra-embryonic region observed in the early trophoblast of in vivo grown mouse NT blastocysts that results in placentomegaly. Author Affiliation: (a) INRA, UMR 1198 Biologie du Developpement et Reproduction, F-78352 Jouy en Josas, France (b) ENVA, F-94704 Maisons Alfort, France (c) INRA, UMR 1197 Neurobiologie de l'Olfaction et de la Prise Alimentaire, Recepteurs et Communication Chimique, Jouy en Josas, France (d) Universite Paris-Sud, UMR1197, Orsay, France Article History: Received 5 May 2009; Revised 12 June 2009; Accepted 9 July 2009

The calcium-sensing receptor (CaSR) controls parathyroid hormone (PTH) secretion, which, in turn, via direct and indirect actions on kidney, bone, and intestine, maintains a normal extracellular ionized calcium concentration ([Ca.sup.2+] o). There is less understanding of the CaSR's homeostatic importance outside of the parathyroid gland. We have employed single and double knockout mouse models, namely mice lacking PTH alone ([CaSR.sup.+/+] [PTH.sup.-/-], referred to as [C.sup.+][P.sup.-]), lacking both CaSR and PTH ([CaSR.sup.-/-] [PTH.sup.-/-], [C.sup.-][P.sup.-]) or wild-type ([CaSR.sup.+/+] [PTH.sup.+/+], [C.sup.+][P.sup.+]) mice to study CaSR-specific functions without confounding CaSR-mediated changes in PTH. The mice received three hypercalcemic challenges: an oral [Ca.sup.2+] load, injection or constant infusion of PTH via osmotic pump, or a phosphate-deficient diet. [C.sup.-][P.sup.-] mice show increased susceptibility to developing hypercalcemia with all three challenges compared with the other two genotypes, whereas [C.sup.+][P.sup.-] mice defend against hypercalcemia similarly to [C.sup.+][P.sup.+] mice. Reduced renal [Ca.sup.2+] clearance contributes to the intolerance of the [C.sup.-][P.sup.-] mice to [Ca.sup.2+] loads, as they excrete less [Ca.sup.2+] at any given [Ca.sup.2+] o than the other two genotypes, confirming the CaSR's direct role in regulating renal [Ca.sup.2+] handling. In addition, [C.sup.+][P.sup.+] and [C.sup.+][P.sup.-], but not [C.sup.-][P.sup.-], mice showed increases in serum calcitonin (CT) levels during hypercalcemia. The level of 1,25[(OH).sub.2][D.sub.3] in [C.sup.-][P.sup.-] mice, in contrast, was similar to those in [C.sup.+][P.sup.-] and [C.sup.+][P.sup.+] mice during an oral [Ca.sup.2+] load, indicating that increased 1,25[(OH).sub.2][D.sub.3] production cannot account for the oral [Ca.sup.2+]-induced hypercalcemia in the [C.sup.-][P.sup.-] mice. Thus, CaSR-stimulated PTH release serves as a 'floor' to defend against hypocalcemia. In contrast, high-[Ca.sup.2+] o-induced inhibition of PTH is not required for a robust defense against hypercalcemia, at least in mice, whereas high-[Ca.sup.2+] o-stimulated, CaSR-mediated CT secretion and renal [Ca.sup.2+] excretion, and perhaps other factors, serve as a 'ceiling' to limit hypercalcemia resulting from various types of hypercalcemic challenges. serum calcium; calcitonin; kidney; vitamin D; urinary calcium; diuretic doi: 10.1152/ajpendo.00315.2009.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2009.06.021 Byline: Lowell Y.M. Rayburn, Jeanne Rhea, Steven R. Jocoy, Michael Bender Keywords: Prohormone convertase; PC2; Pupal development; Metamorphosis; Ecdysis Abstract: Peptide hormones governing many developmental processes are generated via endoproteolysis of inactive precursor molecules by a family of subtilisin-like proprotein convertases (SPCs). We previously identified mutations in the Drosophila amontillado (amon) gene, a homolog of the vertebrate neuroendocrine-specific Prohormone Convertase 2 (PC2) gene, and showed that amon is required during embryogenesis, early larval development, and larval molting. Here, we define amon requirements during later developmental stages using a conditional rescue system and find that amon is required during pupal development for head eversion, leg and wing disc extension, and abdominal differentiation. Immuno-localization experiments show that amon protein is expressed in a subset of central nervous system cells but does not co-localize with peptide hormones known to elicit molting behavior, suggesting the involvement of novel regulatory peptides in this process. The amon protein is expressed in neuronal cells that innervate the corpus allatum and corpora cardiaca of the ring gland, an endocrine organ which is the release site for many key hormonal signals. Expression of amon in a subset of these cell types using the GAL4/UAS system in an amon mutant background partially rescues larval molting and growth. Our results show that amon is required for pupal development and identify a subset of neuronal cell types in which amon function is sufficient to rescue developmental progression and growth defects shown by amon mutants. The results are consistent with a model that the amon protein acts to proteolytically process a diverse suite of peptide hormones that coordinate larval and pupal growth and development. Author Affiliation: Department of Genetics, The University of Georgia, Athens, GA 30602, USA Article History: Received 23 January 2009; Revised 13 May 2009; Accepted 17 June 2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.tibs.2009.02.004 Byline: Christoph Parthier (1), Steffen Reedtz-Runge (2), Rainer Rudolph (1)(3)(4), Milton T. Stubbs (1)(3)(4) Abstract: G-protein-coupled receptors (GPCRs) represent the largest constellation of validated drug targets. Crystal structures of class A GPCRs have facilitated major advances in understanding the principles underlying GPCR activation. By contrast, relatively little is known about class B GPCRs, a family of receptors for a variety of therapeutically relevant peptide hormones. Encouraging progress has recently been made through the structural elucidation of several extracellular hormone-binding domains of class B GPCRs in complex with their natural ligands or synthetic analogues. The structures reveal similar modes of ligand binding, with concomitant [alpha]-helical structuring of the ligand. The latter suggests an attractive mechanical model for class B GPCR activation. Author Affiliation: (1) Institut fur Biochemie und Biotechnologie, Martin-Luther-Universitat Halle-Wittenberg, Kurt-Mothes-StraAe 3, D-06120 Halle (Saale), Germany (2) Department of Structure and Biophysical Chemistry, Novo Nordisk, 2760 MA[yen]lA[cedilla]v, Denmark (3) Mitteldeutsches Zentrum fur Struktur und Dynamik der Proteine, Martin-Luther-Universitat Halle-Wittenberg, D-06120 Halle (Saale), Germany (4) ZIK HALOmem, Martin-Luther-Universitat Halle-Wittenberg, D-06120 Halle (Saale), Germany

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2009.02.032 Byline: Yeon Sook Choi, Rumela Chakrabarti, Rosalba Escamilla-Hernandez, Satrajit Sinha Keywords: Elf5; Conditional knockout; Alveologenesis; Stat5; Transcription Abbreviations: AQP5, aquaporin 5; Cldn7, claudin 7; Elf5, E74-like factor 5; ER[alpha], estrogen receptor alpha; ES, embryonic stem; ESE, epithelium specific Ets; Ets, E twenty-six; Id2, inhibitor of DNA binding 2; IKK[alpha], inhibitor of kappa B kinase alpha; Jak2, janus kinase 2; K14, cytokeratin 14; K18, cytokeratin 18; Lmo4, LIM domain only 4; MMTV, mouse mammary tumor virus; Muc-1, mucin 1; NKCC1, Na-K-Cl cotransporter 1; Npt2b, Na-Pi type IIb cotransporter; PGK-neo, phosphoglycerate kinase-neomycin; PR, progesterone receptor; PrlR, prolactin receptor; SOCS, suppressor of cytokine signaling; Stat5, signal transducer and activator of transcription 5; p-Stat5, phosphorylated Stat5; TEB, terminal end buds; Wap, whey acidic protein Abstract: The transcription factor Elf5 plays an important role in mammary gland development. However, because of the embryonic lethality of Elf5 straight knockout mice, prior studies have been limited to experiments with Elf5 haploinsufficient animals, overexpression systems or transplants. Here, we have utilized K14-Cre to generate mammary-gland specific Elf5 conditional knockout mice. During pregnancy, Elf5-null mammary epithelium completely failed to initiate alveologenesis, and a characteristic of virgin ductal epithelial cells persisted postpartum. We demonstrate that the loss of Elf5 leads to the absence of alveolar secretory markers confirming previous published data. Interestingly, the developmental block due to a lack of Elf5 could not be restored by multiple gestations. Elf5-null mammary epithelial cells also display disorganized cell structures as evident by altered cell polarities, which might be the cause for collapsed lumina. We observe reduced levels of Stat5 and attenuated Stat5 activity as measured by p-Stat5 levels both in Elf5-null mammary glands as well as cultured mammary epithelial cells. This data suggests that the failure of alveolar and lactogenic differentiation due to the loss of Elf5 is mediated in part due to impaired Stat5 activity. In support of this hypothesis, we show by ChIP experiments that Stat5a promoter contains a conserved Elf5-binding site that is occupied by Elf5 in mammary glands. Mammary epithelia lacking Elf5 exhibited downregulation of several other critical genes involved in alveologenesis, suggesting Elf5 as a master regulator in alveolar development. We propose a model for Elf5-mediated alveolar development, in which Elf5 regulates the expression of key mediators of the PrlR/Jak2/Stat5 signaling pathway. Author Affiliation: Department of Biochemistry, State University of New York at Buffalo, Center of Excellence in Bioinformatics and Life Sciences, 701 Ellicott Street, Buffalo, NY 14203, USA Article History: Received 29 July 2008; Revised 20 February 2009; Accepted 20 February 2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.tips.2009.02.004 Byline: Shoba Shetty, Christine M. Kusminski, Philipp E. Scherer Abstract: Adiponectin is a secretory protein predominantly expressed by adipocytes and released at a high rate into circulation. The ease with which the levels of adiponectin can be measured owing to its high abundance, small diurnal variation and high stability in plasma have made it a popular target for measurements in many clinical studies. It has emerged as a valuable biomarker for insulin sensitivity, cardiovascular risk and inflammation. However, adiponectin levels have been measured in many additional disease states. Preclinical studies not only have implicated adiponectin as an outstanding biomarker but also have demonstrated direct cardio-protective and insulin-sensitizing properties to be associated with the protein. Adiponectin might, therefore, be a viable protein therapeutic that could be supplied in a recombinant form in the context of type 2 diabetes and cardiovascular disease. However, the high abundance, complex tertiary and quaternary structure and rapid turnover might make chronic administration of the protein rather challenging. Author Affiliation: Touchstone Diabetes Center, Departments of Internal Medicine and Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390-8549, USA

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2009.01.012 Byline: Manuela Wuelling (a), Frank J. Kaiser (b), Laetitia A. Buelens (a), Diana Braunholz (b), Ramesh A. Shivdasani (d)(e), Reinhard Depping (c), Andrea Vortkamp (a) Keywords: Chondrocyte differentiation; Proliferation; Endochondral ossification; Tricho-Rhino-Phalangeal-syndrome; Indian hedgehog signaling; Gli3 transcription factor Abstract: Trps1, the gene mutated in human Tricho-Rhino-Phalangeal syndrome, represents an atypical member of the GATA-family of transcription factors. Here we show that Trps1 interacts with Indian hedgehog (Ihh)/Gli3 signaling and regulates chondrocyte differentiation and proliferation. We demonstrate that Trps1 specifically binds to the transactivation domain of Gli3 in vitro and in vivo, whereas the repressor form of Gli3 does not interact with Trps1. A domain of 185aa within Trps1, containing three predicted zinc fingers, is sufficient for interaction with Gli3. Using different mouse models we find that in distal chondrocytes Trps1 and the repressor activity of Gli3 are required to expand distal cells and locate the expression domain of Parathyroid hormone related peptide. In columnar proliferating chondrocytes Trps1 and Ihh/Gli3 have an activating function. The differentiation of columnar and hypertrophic chondrocytes is supported by Trps1 independent of Gli3. Trps1 seems thus to organize chondrocyte differentiation interacting with different subsets of co-factors in distinct cell types. Author Affiliation: (a) Center for Medical Biotechnology, Department of Developmental Biology, University Duisburg-Essen, 45117 Essen, Germany (b) Institute for Human Genetics, University of Luebeck, 23538 Luebeck, Germany (c) Department of Physiology, Center for Structural and Cell Biology in Medicine, University of Luebeck, 23538 Luebeck, Germany (d) Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA 02115, USA (e) Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA Article History: Received 19 September 2008; Revised 11 December 2008; Accepted 2 January 2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ahj.2008.05.013 Byline: Daniel G. Hackam (a), Minh L. Duong-Hua (b), Muhammad Mamdani (b)(c), Ping Li (b), Sheldon W. Tobe (d), J. David Spence (a), Amit X. Garg (b)(e) Abstract: Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers effectively reduce blood pressure in patients with renovascular disease (RVD); yet, randomized cardiovascular prevention trials of these drugs typically exclude individuals with this condition. Author Affiliation: (a) Division of Clinical Pharmacology, University of Western Ontario, London, Ontario, Canada (b) Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada (c) Department of Health Policy, Management and Evaluation, University of Toronto, Toronto, Ontario, Canada (d) Division of Nephrology, University of Toronto, Toronto, Ontario, Canada (e) Division of Nephrology, University of Western Ontario, London, Ontario, Canada Article History: Received 28 January 2008; Accepted 6 May 2008 Article Note: (footnote) The study was supported by an unrestricted research grant from the University of Western Ontario, London, Ontario, Canada. None of the funding sources participated in the design or conduct of the research; collection, management, analysis, or interpretation of the data; or the preparation, review, and approval of the manuscript., No conflicts of interest exist for D.G.H., M.L.D., M.M., P.L., or A.X.G. J.D.S. has consulted for Novartis and received lecture fees from Solvay. SWT has participated in research studies, advisory panels, and lectures with support from AstraZeneca, Abbott, Boehringer-Ingelheim, Bristol-Myers Squibb, Sanofi-Aventis, Merck, and Novartis.

Keywords: Aliskiren; moxifloxacin; QT interval; cardiac repolarization 799 Pharmacokinetics and PharmacodynamicsEffects of Aliskiren, a Direct Renin Inhibitor, on Cardiac Repolarization and Conduction in Healthy Subjects SAGE Publications, Inc.200810.1177/0091270008319330 SuryaAyalasomayajula PhD [...]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ahj.2008.01.031 Byline: Saravanan Balamuthusamy, Lavanya Srinivasan, Meenakshi Verma, Sasikanth Adigopula, Nishant Jalandara, Suresh Hathiwala, Earl Smith Abstract: The role of renin angiotensin system (RAS) blockade in controlling hypertension and the positive impact on cardiovascular (CV) outcomes is well known. However, the role of RAS blockade in improving CV outcomes in patients with chronic kidney disease (CKD) is still unclear. Author Affiliation: Division of Nephrology, Department of Medicine, Rosalind Franklin University/Chicago Medical School, Chicago, IL Article History: Received 3 September 2007; Accepted 24 January 2008

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.cell.2008.01.017 Byline: Jing Yang (1), Michael S. Brown (1), Guosheng Liang (1), Nick V. Grishin (2)(3), Joseph L. Goldstein (1) Keywords: PROTEINS; HUMDISEASE; CHEMBIO Abstract: Ghrelin is a 28 amino acid, appetite-stimulating peptide hormone secreted by the food-deprived stomach. Serine-3 of ghrelin is acylated with an eight-carbon fatty acid, octanoate, which is required for its endocrine actions. Here, we identify GOAT (Ghrelin O -Acyltransferase), a polytopic membrane-bound enzyme that attaches octanoate to serine-3 of ghrelin. Analysis of the mouse genome revealed that GOAT belongs to a family of 16 hydrophobic membrane-bound acyltransferases that includes Porcupine, which attaches long-chain fatty acids to Wnt proteins. GOAT is the only member of this family that octanoylates ghrelin when coexpressed in cultured endocrine cell lines with prepro-ghrelin. GOAT activity requires catalytic asparagine and histidine residues that are conserved in this family. Consistent with its function, GOAT mRNA is largely restricted to stomach and intestine, the major ghrelin-secreting tissues. Identification of GOAT will facilitate the search for inhibitors that reduce appetite and diminish obesity in humans. Author Affiliation: (1) Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA (2) Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA (3) Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA Article History: Received 3 December 2007; Revised 8 January 2008; Accepted 17 January 2008 Article Note: (miscellaneous) Published: February 7, 2008

Vasostatins (VSs) are vasoactive peptides derived from chromogranin A (CgA), a protein contained in secretory granules of chromaffin and other cells. The negative inotropic effect and the reduction of isoproterenol (Iso)-dependent inotropism induced by VSs in the heart suggest that they have an antiadrenergic function. However, further investigation of the mechanisms of action of VSs is needed. The aim of the present study was to define the signaling pathways activated by VS-1 in mammalian ventricular myocardium and cultured endothelial cells that lead to the modulation of cardiac contractility. [Ca.sup.2+] and nitric oxide (NO) fluorometric confocal imaging was used to study the effects induced by recombinant human VS-1 [STA-CgA-(1-76)] on contractile force, L-type [Ca.sup.2+] current, and [Ca.sup.2+] transients under basal conditions and after [beta]-adrenergic stimulation in rat papillary muscles and ventricular cells and the effects on intracellular [Ca.sup.2+] concentration and NO production in cultured bovine aortic endothelial (BAE-1) ceils. VS-1 had no effect on basal contractility of papillary muscle, but the effect of Iso stimulation was reduced by 27%. Removal of endocardial endothelium and inhibition of NO synthesis and phosphatidylinositol 3-kinase (PI3K) activity abolished the antiadrenergic effect of VS-1 on papillary muscle. In cardiomyocytes, 10 nM VS-1 was ineffective on basal and Iso (1 [micro]M)-stimulated L-type [Ca.sup.2+] current and [Ca.sup.2+] transients. In BAE-1 cells, VS-1 induced a [Ca.sup.2+]-independent increase in NO production that was blocked by the PI3K inhibitor wortmannin. Our results suggest that the antiadrenergic effect of VS-1 is mainly due to a PI3K-dependent NO release by endothelial cells, rather than a direct action on cardiomyocytes. calcium channel; myocardial contractility; peptide hormones; endothelial cell doi:10.1152/ajpheart.01253.2007

In view of the importance of molecular sensing in the function of the gastrointestinal (GI) tract, we assessed whether signal transduction proteins that mediate taste signaling are expressed in cells of the human gut. Here, we demonstrated that the [alpha]-subunit of the taste-specific G protein gustducin (G[[alpha].sub.gust]) is expressed prominently in cells of the human colon that also contain chromogranin A, an established marker of endocrine cells. Double-labeling immunofluorescence and staining of serial sections demonstrated that G[[alpha].sub.gust] localized to enteroendocrine L cells that express peptide YY and glucagon-like peptide-1 in the human colonic mucosa. We also found expression of transcripts encoding human type 2 receptor (hT2R) family members, hT1R3, and G[[alpha].sub.gust] in the human colon and in the human intestinal endocrine cell lines (HuTu-80 and NCI-H716 cells). Stimulation of HuTu-80 or NCI-H716 cells with the bitter-tasting compound phenylthiocarbamide, which binds hT2R38, induced a rapid increase in the intracellular [Ca.sup.2+] concentration in these cells. The identification of G[[alpha].sub.gust] and chemosensory receptors that perceive chemical components of ingested substances, including drugs and toxins, in open enteroendocrine L cells has important implications for understanding molecular sensing in the human GI tract and for developing novel therapeutic compounds that modify the function of these receptors in the gut. type 2 receptor family; gastrointestinal peptides; peptide YY; glucagon-like peptide-1; chromogranin A; serotonin; phenylthiocarbamide

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ahj.2006.01.007 Byline: Kishlay Anand (a), Aryan N. Mooss (a)(b), Tom T. Hee (a)(b), Syed M. Mohiuddin (a)(b) Abstract: Epidemiologic studies suggest that inhibition of renin-angiotensin system with angiotensin-converting enzyme inhibitors and angiotensin receptor blockers may prevent development of atrial fibrillation (AF). Author Affiliation: (a) Department of Internal Medicine, Creighton University, Omaha, NE (b) Division of Cardiology, Creighton University, Omaha, NE Article History: Received 17 August 2005; Accepted 22 January 2006

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ahj.2006.02.028 Byline: John J.V. McMurray (a), James B. Young (b), Mark E. Dunlap (c), Christopher B. Granger (d), James Hainer (e), Eric L. Michelson (e), Steven Earle (e), Bertil Olofsson (f), Jan Astergren (g), Salim Yusuf (h), Karl Swedberg (i), Marc A. Pfeffer (j) Abstract: Whether an angiotensin receptor blocker is of benefit when added to a full dose of angiotensin-converting enzyme (ACE) inhibitor in heart failure (HF) is uncertain. Author Affiliation: (a) Department of Cardiology, Western Infirmary, Glasgow, Scotland (b) Medicine, Cleveland Clinic Foundation, Cleveland, OH (c) Case Western Reserve University and VA Medical Center, Cleveland, OH (d) Duke University Medical Center, Durham, NC (e) AstraZeneca LP, Wilmington, DE (f) AstraZeneca, R&D Molndal, Sweden (g) Department of Medicine, Karolinska University Hospital Solna, Stockholm, Sweden (h) HGM-McMaster Clinic, Hamilton, Ontario, Canada (i) Department of Medicine, Sahlgrenska University Hospital/Astra, Goteborg, Sweden (j) Brigham and Women's Hospital, Boston, MA Article History: Received 30 December 2005; Accepted 14 February 2006 Article Note: (footnote) The CHARM program was funded by AstraZeneca, Wilmington, DE, which was responsible for data collection and analysis. Academic leadership was provided by the executive committee who supervised the management of the study and was responsible for the interpretation of the data, preparation, review, and approval of the manuscript. Authors who are employees of AstraZeneca are identified as such. All other authors have received research grants, consultancy fees, and/or speaker fees from AstraZeneca. Guest editor of this manuscript is Harvey D. White, DSc.

This paper describes a novel two-site peptide immunoassay using the isotope [sup.14]C as the label and accelerator mass spectrometry as the detection system. A mouse monoclonal antibody (1A5) against the amino terminal region of human parathyroid hormone-related protein (PTHrP) was labeled with [sup.14]C by growing the hybridoma cells in a miniPERM bioreactor in the presence of [U-[sup.]14C]L-leucine and [U-[sup.14]C]D-glucose. The antibody was purified from the culture media using protein G affinity chromatography. The purified [sup.14]C-labeled antibody ([sup.14]C-1A5) fractions showed excellent correlation between the levels of radioactivity and binding activity for PTHrP. Using [sup.14]C-1A5 as the detection antibody in a two-site immunoassay format for PTHrPI-141, a 16-kDa polypeptide, an analytic sensitivity of 10 pmol/L was achieved with a linear measurement range up to 1.3 nmol/L Only ~17 pCi/ well (or 1.6 nCi/96-weH microtiter plate) [sup.14]C-1A5 was used, which is far below the limit (50 nCi/g) for disposal as nonradioactive waste. This study may serve as a model for the development of sensitive and 'nonradioactive' immunoassays for peptides, including polypeptide tumor markers.

The insect adipokinetic hormones (AKHs) are a large family of peptide hormones that are involved in the mobilization of sugar and lipids from the insect fat body during energy-requiring activities such as flight and locomotion, but that also contribute to hemolymph sugar homeostasis. Here, we have identified the first insect AKH receptors, namely those from the fruitfly Drosophila melanogaster and the silkworm Bombyx mori. These results represent a breakthrough for insect molecular endocrinology, because it will lead to the cloning of all AKH receptors from all model insects used in AKH research, and, therefore, to a better understanding of AKH heterogeneity and actions. Interestingly, the insect AKH receptors are structurally and evolutionarily related to the gonadotropin-releasing hormone receptors from vertebrates.

Results show that cCF10 peptide of Enterococcus faecalis possesses pheromone activity and the peptide is associated with both cell wall and membrane fractions. Data further reveal that protease inhibitors affect its activity and a maturase or protease is capable of processing pro-cCF10 into a mature cCF10.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/S0002-8703(00)90315-6 Byline: Tamas Szombathy, Livia Janoskuti, Csaba Szalai, Albert Csaszar, Miklos Miklosi, Zsuzsa Meszaros, Pal Kempler, Zoltan Laszlo, Tamas Fenyvesi, Laszlo Romics Abstract: Background Mitral valve prolapse syndrome (MVPS), a term applied to patients who have a variety of symptoms, has been associated with autonomic or neuroendocrine dysfunction. Recent evidence suggests that effects of angiotensin II mediated by the angiotensin II type 1 (AT.sub.1) receptor are involved in modulation of cardiovascular autonomic control in human beings. Association of a genetic polymorphism (A-C.sup.1166) of the AT.sub.1 gene with abnormal vasomotion and low blood pressure related to autonomic control has been reported recently. Because the role of this genetic variant in MVPS has not been studied, we performed a case-control study of the A-C.sup.1166 variant in a group of 76 white subjects with MVPS. Methods and Results All patients were genotyped by use of a mismatch polymerase chain reaction/Afl II restriction fragment length polymorphism analysis. Frequency of the C.sup.1166 allele was 0.4 in patients with MVPS and 0.26 in control patients. The difference in genotype (chi square = 6.5; P < .05) and allele (chi square = 5.9; P = .02) frequencies between the groups was significant. The odds ratio in favor of carrying the C allele was 4 times greater for patients with MVP than for control patients (95% confidence interval 1.4 to 12.1). Conclusions The current results indicate that the A-C.sup.1166 polymorphism of the angiotensin II type 1 receptor gene is associated with MVPS in the white population. (Am Heart J 2000;139:101-5.) Author Affiliation: Budapest, Hungary From the.sup.aThird Department of Medicine, the Division of Cardiology, and the.sup.bDepartment of Pharmacodynamics, Semmelweis University..sup.CHeim Pal's Hospital, Molecular Genetics Laboratory; and the.sup.dDepartment of Cardiology, Szent Margit's Hospital Article History: Received 17 June 1998; Accepted 7 October 1998 Article Note: (footnote) [star] Supported by grant OTKA T016750 from the National Scientific Research Fund., [star][star] Reprint requests: Tamas Szombathy, MD, Third Department of Medicine, Semmelweis University, 4 Kutvolgyi ut, Budapest, 1125, Hungary., a 0002-8703/2000/$12.00 + 0 4/1/95077

Byline: Markus P. Schlaich, Arnfried Klingbeil, Karl Hilgers, Hans P. Schobel, Roland E. Schmieder Abstract: Background: High angiotensin II levels in relation to the corresponding urinary sodium excretion have been found to modulate left ventricular (LV) structure in middle-aged hypertensive patients. To analyze whether such a relation between the renin-angiotensin-aldosterone system and left ventricular structure is already present in young individuals, we examined the changes of angiotensin II and aldosterone in response to increased salt intake and their relations to LV structure and function. Methods: In 119 young (aged 26 [+ or -] 3 years) patients with normal or mildly elevated blood pressure, we determined LV structure and function (2-dimensional guided M-mode echocardiography and pulse wave Doppler sonography) and 24-hour ambulatory blood pressure (SpaceLabs 90207). Dietary sodium intake as estimated by 24-hour urinary sodium excretion, plasma renin activity, angiotensin II, and aldosterone concentrations were measured first on a normal diet and second at high salt intake to determine the extent of the resulting suppression of the renin-angiotensin-aldosterone system. Results: Body mass index (r = 0.43, P < .001) and both systolic (r = 0.24, P < .01) and diastolic (r = 0.19, P < .05) 24-hour ambulatory blood pressure correlated with LV mass. No straightforward relation was found between LV structure and baseline angiotensin II or aldosterone concentration. The increase of sodium excretion at high salt intake was related to a physiologically expected decrease of angiotensin II and aldosterone levels in normotensive (r = -0.36, P < .01 and r = -0.32; P = .016, respectively) but not in hypertensive patients. Changes in angiotensin II or aldosterone concentration were not related to LV structure in either hypertensive or normotensive young individuals. However, changes in aldosterone secretion correlated with diastolic filling parameters in hypertensive patients (velocity-time integrals of the A over E wave: r = 0.32, P = .03; atrial contribution of LV filling: r = 0.33, P = .025) but not in normotensive individuals. Conclusion: In contrast to middle-aged hypertensive patients, neither angiotensin II, aldosterone, nor their suppression in response to high salt intake were related to LV structure in young hypertensive patients. However, inadequate suppression of aldosterone after salt intake was associated with diastolic filling abnormalities in our young hypertensive patients, which may represent early changes in hypertensive heart disease and precede potential structural alterations. (Am Heart J 1999;138:810-7.) Author Affiliation: Nurnberg, Germany From the Department of Medicine IV/Nephrology, University of Erlangen-Nurnberg Article History: Received 15 April 1997; Accepted 27 January 1999 Article Note: (footnote) [star] Supported by a grant from the Deutsche Forschungsgesellschaft (Schm 638/8-1/2)., [star][star] Reprint requests: Roland E. Schmieder, MD, Medizinische Klinik IV/Nephrology, Universitat Erlangen-Nurnberg, Breslauer Str. 201, D-90471 Nurnberg, Germany., a 0002-8703/99/$8.00 + 0 4/1/99147

Byline: Kazuyuki Sakata, Manabu Shirotani, Hiroshi Yoshida, Tetsumei Urano, Yumiko Takada, Akikazu Takada Abstract: Background Impaired fibrinolysis is associated with thromboembolic complications in hypertensive patients. It has been reported that cardiovascular morbidity and mortality rates are high even after lowering the elevated blood pressure with antihypertensive drugs. The aim of this study was to assess the effect of clinically used dosages of enalapril and nitrendipine on the fibrinolytic system. Methods Tissue plasminogen activator antigen (tPA) and tissue plasminogen activator inhibitor-1 (PAI-1) activity were measured in 20 normotensive male subjects and 46 male patients with mild essential hypertension divided into 2 groups (22 patients treated with 5 to 10 mg enalapril once a day and 24 treated with 5 to 10 mg nitrendipine once a day) before and 3 months after drug administration. Plasma renin activity and norepinephrine concentration were also measured. Results There were no significant differences in basal characteristics between the 2 hypertensive groups. In both hypertensive groups, blood pressure was significantly reduced to a similar level after drug treatment. In the 2 hypertensive groups, plasma renin activity significantly increased after drug treatment; however, there were no significant changes in norepinephrine concentration. Before drug treatment, the 2 hypertensive groups had significantly higher tPA and higher PAI-1 activity than the normotensive subjects. In the enalapril group, there was no significant change in tPA although PAI-1 activity significantly decreased after drug treatment. In the nitrendipine group, there was no significant change in tPA although PAI-1 activity significantly increased after drug treatment. Conclusion Thus enalapril improved impaired fibrinolysis but nitrendipine further aggravated fibrinolysis in essential hypertension. Considering the effect of antihypertensive drugs on the fibrinolytic system, more effective and beneficial treatment of hypertensives, especially at a high risk for thrombus formation might be selected. (Am Heart J 1999;137:1094-9.) Author Affiliation: Shizuoka and Hamamatsu, Japan From.sup.athe Department of Cardiology, Shizuoka General Hospital, and the Departments of.sup.bPhysiology and.sup.cPathophysiology, Hamamatsu University School of Medicine Article History: Received 29 May 1998; Accepted 10 August 1998 Article Note: (footnote) [star] Reprint requests: Kazuyuki Sakata, MD, Department of Cardiology, Shizuoka General Hospital, 4-27-1 Kita-andou, Shizuoka, Japan., [star][star] 0002-8703/99/$8.00 + 0 4/1/93840

Byline: Andrea Giustina, Maurizio Volterrani, Filippo Manelli, Paolo Desenzani, Claudio Poiesi, Roberto Lorusso, Amerigo Giordano Abstract: Background The aim of our study was to assess whether there could be any clinical and/or endocrine (spontaneous growth hormone [GH] secretion rate, baseline insulin-like growth factor-1 [IGF-1]) predictors and/or determinants of the acute effects of continuous intravenous infusion of recombinant human GH on hemodynamic parameters in 12 patients with dilated cardiomyopathy and congestive heart failure (CHF). Methods And Results The study involved 12 male patients with chronic CHF (ischemic in 8 patients and idiopathic in 4). Ten patients were in New York Heart Association functional class III or IV and 2 in class II. The first 24 hours were considered the control period; in fact, during the following 24 hours, all the patients underwent intravenous constant pump infusion of recombinant human GH. Blood samples for GH assay were taken every 20 minutes during the first night of the study (from 10 PM to 6 AM). Moreover, blood samples for GH assay were also taken during exogenous GH infusion. Blood samples for IGF-1 assays were taken at 8 AM of each of the 3 days of the study. Pulmonary artery pressure (PAP) and capillary wedge (PCWP) pressure, cardiac index, and arterial blood pressure were measured 30 minutes after right heart catheterization (baseline 1), at the end of the control period (baseline 2), and every 4 hours during GH infusion. A negative correlation has been found between mean nocturnal GH levels and baseline IGF-1 levels (r = -0.47, P = .124) and between mean nocturnal GH levels and both postinfusion absolute (r = -0.67, P < .05) and delta (postinfusion-preinfusion) (r = -0.58; P < 005) IGF-1 levels. No significant correlations have been found between several parameters of liver function (albumin, bilirubin, and pseudocholinesterase) and mean nocturnal GH. However, baseline IGF-1 levels showed a negative significant correlation (r = -0.76, P < .01) with total bilirubin and a positive correlation (r = 0.72, P < .01) with pseudocholinesterase. Baseline IGF-1 levels showed a significant negative correlation with baseline mean PAP (r = -0.68, P < .05) and PCWP (r = -0.70, P < .05) and a positive correlation with baseline cardiac index (r = 0.71, P < .05). Baseline IGF-1 levels also showed a significant negative correlation with absolute mean PAP (r = -0.63, P < .05) and mean PCWP (r = -0.67, P < .05) after GH infusion. After GH infusion, IGF-1 levels also negatively correlated with post-GH infusion mean PAP (r = -0.50, P = .09) and mean PCWP (r = -0.66, P < .05). The positive correlation between either baseline or postinfusion IGF-1 and the postinfusion cardiac index (r = 0.40 and 0.43, respectively) did not reach statistical significance. Conclusions GH has acute functional effects on the heart in patients with CHF, including both an increase in myocardial contractility and a decrease in vascular resistances, and among patients with CHF, those with low baseline IGF-1 are likely to have fewer beneficial effects from GH infusion. (Am Heart J 1999;137:1035-43.) Author Affiliation: Brescia and Gussago, Italy From the Endocrine, Chemistry, and Cardiac Surgery Sections, University of Brescia; 'Salvatore Maugeri' Foundation, IRCCS Rehabilitation Institute, Division of Cardiology Article History: Received 15 August 1997; Accepted 23 February 1998 Article Note: (footnote) [star] Supported in part by the Centro Studi e Ricerche di Neuroendocrinologia, Brescia, and funded by a current research grant of 'Salvatore Maugeri' Foundation., [star][star] Reprint requests: Dr Andrea Giustina, Endocrine Section, Clinica Medica, c/o 2^ Medicina, Spedali Civili, P.le Spedali Civili, 1, 25123 Brescia, Italy., a 0002-8703/99/$8.00 + 0 4/1/93849

Byline: W.David Hager, Barry R. Davis, Arthur Riba, Lemuel A. Moye, Chuan-Chuan Wun, Jean L. Rouleau, Gervasio A. Lamas, Marc A. Pfeffer Abstract: Background As a result of randomized controlled trials with calcium channel blockers after myocardial infarction, concern has developed that these agents are associated with an increased risk of cardiovascular events, particularly in the presence of left ventricular dysfunction. Methods To test the hypothesis that calcium channel blockers increase cardiovascular events in such patients, the incidence of all-cause mortality, cardiovascular death, severe heart failure, and recurrent infarction was examined in 940 patients taking calcium channel blockers and 1180 not taking them 24 hours before randomization to placebo or captopril in the Survival and Ventricular Enlargement (SAVE) Trial. All patients had an ejection fraction [less than or equal to]40%. Relative risks for calcium channel blocker users versus nonusers and the 95% confidence intervals were computed with univariate and multivariate Cox regressions. Adjustments were made for differences in baseline covariates. Results For all causes of mortality, the relative risk for calcium channel blocker users versus nonusers was 0.96, with the 95% confidence interval of 0.78 to 1.17. In the SAVE placebo and captopril groups, the relative risks for the development of severe heart failure among the calcium channel block users versus nonusers were 0.95 and 1.23, with the 95% confidence interval of 0.72 to 1.25 and 0.88 to 1.71, respectively. A similar neutral result held for patients with and without a history of hypertension. Furthermore, calcium channel blockers did not alter the benefit of the angiotensin converting enzyme inhibitor, captopril. Conclusions This analysis of the nonrandomized clinical use of calcium channel blockers in the postmyocardial infarction population with left ventricular dysfunction did not identify either a clinical deterioration or improvement with respect to subsequent cardiovascular events. (Am Heart J 1998;135:406-13.) Author Affiliation: Farmington, Conn.; Houston, Texas; Dearborn, Mich.; Montreal, Quebec, Canada; Miami Beach, Fla.; and Boston, Mass Article History: Received 27 May 1997; Accepted 31 October 1997 Article Note: (footnote) [star] From the aDivision of Cardiology, University of Connecticut Health Center, Farmington; bSchool of Public Health, University of Texas, Houston; cOakwood Hospital, Dearborn; dInstitut de Cardiologie de Montreal; eCardiology Division, Mount Sinai Medical Center, Miami Beach; and fCardiovascular Division, Brigham and Women's Hospital, Boston., [star][star] Reprint requests: W. David Hager, MD, Cardiology Division -- L-3104, Univeristy of Connecticut Health Center, Farmington, CT 06030., a 0002-8703/98/$5.00 + 0 4/1/88150

Conformational analysis studies and Chou-Fasman analysis established the predominance of alpha-helix in parathyroid hormone receptor protein (PTHrP). The results indicated that in aqueous solution, all three lactam-containing PTHrP analogs have enhanced helicity compared to the linear parent compound PTHrP in water. This confirmed that lactams contribute to the stability of helical motifs.