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Sample records for angiotensin receptor gene

  1. Angiotensin type 2 receptors

    DEFF Research Database (Denmark)

    Sumners, Colin; de Kloet, Annette D; Krause, Eric G;

    2015-01-01

    In most situations, the angiotensin AT2-receptor (AT2R) mediates physiological actions opposing those mediated by the AT1-receptor (AT1R), including a vasorelaxant effect. Nevertheless, experimental evidence vastly supports that systemic application of AT2R-agonists is blood pressure neutral....... However, stimulation of AT2R locally within the brain or the kidney apparently elicits a systemic blood pressure lowering effect. A systemic effect of AT2R stimulation on blood pressure can also be achieved, when the prevailing effect of continuous background AT1R-stimulation is attenuated by low-dose AT1......R blockade. Despite a lack of effect on blood pressure, AT2R stimulation still protects from hypertensive end-organ damage. Current data and evidence therefore suggest that AT2R agonists will not be suitable as future anti-hypertensive drugs, but that they may well be useful for end-organ protection...

  2. Increased angiotensin II AT(1) receptor expression in paraventricular nucleus and hypothalamic-pituitary-adrenal axis stimulation in AT(2) receptor gene disrupted mice.

    Science.gov (United States)

    Armando, Inés; Terrón, José A; Falcón-Neri, Alicia; Takeshi, Ito; Häuser, Walter; Inagami, Tadashi; Saavedra, Juan M

    2002-09-01

    Angiotensin II AT(2) receptor gene-disrupted mice have increased blood pressure and response to angiotensin II, behavioral alterations, greater response to stress, and increased adrenal AT(1) receptors. We studied hypothalamic AT(1) receptor binding and mRNA by receptor autoradiography and in situ hybridization, adrenal catecholamines by HPLC, adrenal tyrosine hydroxylase mRNA by in situ hybridization and pituitary and adrenal hormones by RIA in AT(2) receptor-gene disrupted mice and wild-type controls. To confirm the role of adrenal AT(1) receptors, we treated wild-type C57 BL/6J mice with the AT(1) antagonist candesartan for 2 weeks, and measured adrenal hormones, catecholamines and tyrosine hydroxylase mRNA. In the absence of AT(2) receptor transcription, we found increased AT(1) receptor binding in brain areas involved in the regulation of the hypothalamic-pituitary-adrenal axis, the hypothalamic paraventricular nucleus and the median eminence, and increased adrenal catecholamine synthesis as shown by higher adrenomedullary tyrosine hydroxylase mRNA and higher adrenal dopamine, norepinephrine and epinephrine levels when compared to wild-type mice. In addition, in AT(2) receptor gene-disrupted mice there were higher plasma adrenocorticotropin (ACTH) and corticosterone levels and lower adrenal aldosterone content when compared to wild-type controls. Conversely, AT(1) receptor inhibition in CB57 BL/6J mice reduced adrenal tyrosine hydroxylase mRNA and catecholamine content and increased adrenal aldosterone content. These results can help to explain the enhanced response of AT(2) receptor gene-disrupted mice to exogenous angiotensin II, support the hypothesis of cross-talk between AT(1) and AT(2) receptors, indicate that the activity of the hypothalamic-pituitary-adrenal axis parallels the AT(1) receptor expression, and suggest that expression of AT(1) receptors can be dependent on AT(2) receptor expression. Our results provide an explanation for the increased

  3. Circadian expression of clock genes and angiotensin Ⅱ type 1 receptors in suprachiasmatic nuclei of sinoaortic-denervated rats

    Institute of Scientific and Technical Information of China (English)

    Hui LI; Ning-ling SUN; Jin WANG; Ai-jun LIU; Ding-feng SU

    2007-01-01

    Aim: To investigate whether the circadian expression of central clock genes and angiotensin Ⅱ type 1 (AT1) receptors was altered in sinoaortic-denervated (SAD)rats. Methods: Male Sprague-Dawley rats underwent sinoaortic denervation or a sham operation at the age of 12 weeks. Four weeks after the operation, blood pressure and heart period were measured in the conscious state in a group of sham-operated (n=10) and SAD rats (n=9). Rest SAD and sham-operated rats were divided into 6 groups (n=6 in each group). The suprachiasmatic nuclei (SCN)tissues were taken every 4 h throughout the day from each group for the determi-nation of the mRNA expression of clock genes (Per2 and Bmall) and the AT1receptor by RT-PCR; the protein expression of Per2 and Bmall was determined by Western blotting. Results: Blood pressure levels in the SAD rats were similar to those of the sham-operated rats. However, blood pressure variabilities signifi-cantly increased in the SAD rats compared with the sham-operated rats. The circadian variation of clock genes in the SCN of the sham-operated rats was char-acterized by a marked increase in the mRNA and protein expression during dark periods. Per2 and Bmall mRNA levels were significantly lower in the SAD rats,especially during dark periods. Western blot analysis confirmed an attenuation of the circadian rhythm of the 2 clock proteins in the SCN of the SAD rats. AT1 receptor mRNA expressions in the SCN were abnormally upregulated in the light phase, changed to a 12-h cycle in the SAD rats. Conclusion: The circadian varia-tion of the 2 central clock genes was attenuated in the SAD rats. Arterial baroreflex dysfunction also induced a disturbance in the expression of AT1 receptors in the SCN.

  4. Activation of the retinoid X receptor modulates angiotensin II-induced smooth muscle gene expression and inflammation in vascular smooth muscle cells.

    Science.gov (United States)

    Lehman, Allison M B; Montford, John R; Horita, Henrick; Ostriker, Allison C; Weiser-Evans, Mary C M; Nemenoff, Raphael A; Furgeson, Seth B

    2014-11-01

    The retinoid X receptor (RXR) partners with numerous nuclear receptors, such as the peroxisome proliferator activated receptor (PPAR) family, liver X receptors (LXRs), and farnesoid X receptor (FXR). Although each heterodimer can be activated by specific ligands, a subset of these receptors, defined as permissive nuclear receptors, can also be activated by RXR agonists known as rexinoids. Many individual RXR heterodimers have beneficial effects in vascular smooth muscle cells (SMCs). Because rexinoids can potently activate multiple RXR pathways, we hypothesized that treating SMCs with rexinoids would more effectively reverse the pathophysiologic effects of angiotensin II than an individual heterodimer agonist. Cultured rat aortic SMCs were pretreated with either an RXR agonist (bexarotene or 9-cis retinoic acid) or vehicle (dimethylsulfoxide) for 24 hours before stimulation with angiotensin II. Compared with dimethylsulfoxide, bexarotene blocked angiotensin II-induced SM contractile gene induction (calponin and smooth muscle-α-actin) and protein synthesis ([(3)H]leucine incorporation). Bexarotene also decreased angiotensin II-mediated inflammation, as measured by decreased expression of monocyte chemoattractant protein-1 (MCP-1). Activation of p38 mitogen-activated protein (MAP) kinase but not extracellular signal-related kinase (ERK) or protein kinase B (Akt) was also blunted by bexarotene. We compared bexarotene to five agonists of nuclear receptors (PPARα, PPARγ, PPARδ, LXR, and FXR). Bexarotene had a greater effect on calponin reduction, MCP-1 inhibition, and p38 MAP kinase inhibition than any individual agonist. PPARγ knockout cells demonstrated blunted responses to bexarotene, indicating that PPARγ is necessary for the effects of bexarotene. These data demonstrate that RXR is a potent modulator of angiotensin II-mediated responses in the vasculature, partially through inhibition of p38. PMID:25169989

  5. A polymorphism in the angiotensin II type 1 receptor gene has different effects on the risk of diabetic nephropathy in men and women

    DEFF Research Database (Denmark)

    Möllsten, Anna; Vionnet, Nathalie; Forsblom, Carol;

    2011-01-01

    -control study investigated the association of the rs5186 polymorphism, in the angiotensin II type 1 receptor gene (AGTR1), with diabetic nephropathy. The study included 3561 patients with type 1 diabetes from Denmark, Finland, France and Sweden. Microalbuminuria was defined as albumin excretion rate (AER) ≥20......BACKGROUND: The etiology of diabetic nephropathy depends partly on genetic factors. Elevated systemic and intraglomerular blood pressure and glomerular filtration rate, partly regulated by the renin-angiotensin system, increase the risk of diabetic nephropathy. METHODS: The present case...... to 15 years diabetes duration, AER

  6. ROLE OF ANGIOTENSIN-CONVERTING ENZYME AND VITAMIN D RECEPTOR GENE POLYMORPHISMS IN CANCER ANOREXIA-CACHEXIA SYNDROME

    Directory of Open Access Journals (Sweden)

    Ariele Fabris

    2012-01-01

    Full Text Available The ubiquitin-proteasome pathway is a crucial connection between aberrant immune system activation, systemic inflammation and Cancer Anorexia-Cachexia Syndrome (CACS, a syndrome that culminates in hyper-activation of the ubiquitin-proteasome pathway. Angiotensin directly up-regulates this pathway, while vitamin D down-regulates it indirectly through the insulin-like growth factor-1 pathway. We investigated the genetic predisposition towards CACS in a cancer population, examining Insertion/Deletion (I/D polymorphism of angiotensin-converting enzyme gene and FokI and BsmI polymorphisms of vitamin D receptor gene. Sixty-two cancer patients were recruited and divided into three groups: primary cachectic (C1, n = 14; dysmetabolic body weight loss ≥5% in 6 months; secondary cachectic (C2, n = 34; similar weight loss, mechanic or iatrogenic origin; and non-cachectic (NC, n = 16. C2+NC were merged in the control group. The three groups showed significant differences in average prognostic inflammatory nutritional index (C1: 26.4±23.4; C2: 5.4±5.6; NC: 0.37±0.5, C-reactive protein serum levels (C1: 6.6±2.1; C2: 2.4±2.2; NC: 1.0±2.0 mg/dL, albumin serum levels (C1: 3.1±0.6; C2: 3.5±0.4; NC 3.7±0.6 g/dL, weight loss (C1: 22±8; C2: 15±6.7; NC 5±6% and life expectancy (C1: 6.4±3.3; C2: 25±28; NC: 45±25 months. However, none of the chosen polymorphisms showed any statistically significant correlation with CACS. The complexity of the changes of the immune system in the chronic inflammation state associated with CACS is far greater than expected and further studies are required to identify genetic independent markers of progression toward CACS."

  7. Association of Angiotensin-Converting Enzyme Intron 16 Insertion/Deletion and Angiotensin II Type 1 Receptor A1166C Gene Polymorphisms with Preeclampsia in South East of Iran

    Directory of Open Access Journals (Sweden)

    Saeedeh Salimi

    2011-01-01

    Full Text Available Some evidence suggests that a variety of genetic factors contributed in pathogenesis of the preeclampsia. The aim of this study was to assess the association between the angiotensin-converting enzyme (ACE I/D and angiotensin II type1 receptor A1166C polymorphisms with preeclampsia. This study was performed in 125 preeclamptic pregnant women and 132 controls. The I/D Polymorphism of the ACE gene was assessed by polymerase chain reaction and the A1166C Polymorphism of the AT1R gene was determined by restriction fragment length polymorphism. The genotype and allele frequencies of I/D polymorphism differed between two groups. The risk of preeclampsia was 3.2-fold in pregnant women with D allele (OR, 3.2 [95% CI, 1.1 to 3.8]; P=0.01. The distribution of the AT1R gene A1166C polymorphism was similar in affected and control groups. Our results supported that presence of the I/D polymorphism of ACE gene is a marker for the increased risk of preeclampsia.

  8. Angiotensin Receptors, Autoimmunity, and Preeclampsia1

    OpenAIRE

    Xia, Yang; Zhou, Cissy Chenyi; RAMIN, Susan M.; Kellems, Rodney E.

    2007-01-01

    Preeclampsia is a pregnancy-induced hypertensive disorder that causes substantial maternal and fetal morbidity and mortality. Despite being a leading cause of maternal death and a major contributor to maternal and perinatal morbidity, the mechanisms responsible for the pathogenesis of preeclampsia are poorly understood. Recent studies indicate that women with preeclampsia have autoantibodies that activate the angiotensin receptor, AT1, and that autoantibody-mediated receptor activation contri...

  9. Differential roles of Angiotensinogen and Angiotensin Receptor type 1 polymorphisms in breast cancer risk.

    NARCIS (Netherlands)

    Gonzalez-Zuloet Ladd, A.M.; Arias Vasquez, A.; Siemes, C.; Yazdanpanah, M.; Coebergh, J.W.W.; Hofman, A.; Stricker, B.H.C.; Duijn, C.M. van

    2007-01-01

    While angiotensinogen (AGT) seems to have anti proliferative properties, angiotensin II (ATII) is a potent growth factor and it mediates its actions through the angiotensin type 1 receptor (AGTR1). In the AGT gene, the M235T polymorphism has been associated with the variation in angiotensinogen leve

  10. Documentation of angiotensin II receptors in glomerular epithelial cells

    Science.gov (United States)

    Sharma, M.; Sharma, R.; Greene, A. S.; McCarthy, E. T.; Savin, V. J.; Cowley, A. W. (Principal Investigator)

    1998-01-01

    Angiotensin II decreases glomerular filtration rate, renal plasma flow, and glomerular capillary hydraulic conductivity. Although angiotensin II receptors have been demonstrated in mesangial cells and proximal tubule cells, the presence of angiotensin II receptors in glomerular epithelial cells has not previously been shown. Previously, we have reported that angiotensin II caused an accumulation of cAMP and a reorganization of the actin cytoskeleton in cultured glomerular epithelial cells. Current studies were conducted to verify the presence of angiotensin II receptors by immunological and non-peptide receptor ligand binding techniques and to ascertain the activation of intracellular signal transduction in glomerular epithelial cells in response to angiotensin II. Confluent monolayer cultures of glomerular epithelial cells were incubated with angiotensin II, with or without losartan and/or PD-123,319 in the medium. Membrane vesicle preparations were obtained by homogenization of washed cells followed by centrifugation. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of membrane proteins followed by multiscreen immunoblotting was used to determine the presence of angiotensin II receptor type 1 (AT1) or type 2 (AT2). Angiotensin II-mediated signal transduction in glomerular epithelial cells was studied by measuring the levels of cAMP, using radioimmunoassay. Results obtained in these experiments showed the presence of both AT1 and AT2 receptor types in glomerular epithelial cells. Angiotensin II was found to cause an accumulation of cAMP in glomerular epithelial cells, which could be prevented only by simultaneous use of losartan and PD-123,319, antagonists for AT1 and AT2, respectively. The presence of both AT1 and AT2 receptors and an increase in cAMP indicate that glomerular epithelial cells respond to angiotensin II in a manner distinct from that of mesangial cells or proximal tubular epithelial cells. Our results suggest that glomerular epithelial

  11. Trends in co-prescribing of angiotensin converting enzyme inhibitors and angiotensin receptor blockers in Ireland.

    LENUS (Irish Health Repository)

    Wan Md Adnan, Wan A H

    2011-03-01

    (i) To examine the trends in co-prescribing of angiotensin converting enzyme inhibitor (ACEI) and angiotensin-II receptor blocker (ARB) therapy and (ii) to examine the influence of major clinical trials (CALM, COOPERATE, VALIANT and ONTARGET) on co-prescribing.

  12. Angiotensin II (AT1) Receptor Blockade Reduces Vascular Tissue Factor in Angiotensin II-Induced Cardiac Vasculopathy

    OpenAIRE

    Dominik N Müller; Mervaala, Eero M A; Dechend, Ralf; Fiebeler, Anette; Park, Joon-Keun; Schmidt, Folke; Theuer, Jürgen; Breu, Volker; Mackman, Nigel; Luther, Thomas; Schneider, Wolfgang; Gulba, Dietrich; Ganten, Detlev; Haller, Hermann; Luft, Friedrich C.

    2000-01-01

    Tissue factor (TF), a main initiator of clotting, is up-regulated in vasculopathy. We tested the hypothesis that chronic in vivo angiotensin (ANG) II receptor AT1 receptor blockade inhibits TF expression in a model of ANG II-induced cardiac vasculopathy. Furthermore, we explored the mechanisms by examining transcription factor activation and analyzing the TF promoter. Untreated transgenic rats overexpressing the human renin and angiotensinogen genes (dTGR) feature hypertension and severe left...

  13. ROLE OF ANGIOTENSIN-CONVERTING ENZYME AND VITAMIN D RECEPTOR GENE POLYMORPHISMS IN CANCER ANOREXIA-CACHEXIA SYNDROME

    OpenAIRE

    Ariele Fabris; Paolo Biagioni; Tiziana Punzi; Gabriele Morucci; Massimo Gulisano; Stefania Pacini; Marco Ruggiero

    2012-01-01

    The ubiquitin-proteasome pathway is a crucial connection between aberrant immune system activation, systemic inflammation and Cancer Anorexia-Cachexia Syndrome (CACS), a syndrome that culminates in hyper-activation of the ubiquitin-proteasome pathway. Angiotensin directly up-regulates this pathway, while vitamin D down-regulates it indirectly through the insulin-like growth factor-1 pathway. We investigated the genetic predisposition towards CACS in a cancer population, examining Insertion/De...

  14. Review: Novel roles of nuclear angiotensin receptors and signaling mechanisms

    OpenAIRE

    Gwathmey, TanYa M.; Alzayadneh, Ebaa M.; Karl D. Pendergrass; Chappell, Mark C.

    2011-01-01

    The renin-angiotensin system (RAS) constitutes an important hormonal system in the physiological regulation of blood pressure. The dysregulation of the RAS is considered a major influence in the development and progression of cardiovascular disease and other pathologies. Indeed, experimental and clinical evidence indicates that blockade of this system with angiotensin-converting enzyme (ACE) inhibitors or angiotensin type 1 receptor (AT1R) antagonists is an effective therapy to attenuate hype...

  15. The Angiotensin AT2 Receptor

    DEFF Research Database (Denmark)

    Unger, Thomas; Steckelings, Ulrike M.; Dzau, Victor J.

    2015-01-01

    Since its discovery, 25 years ago, the angiotensin AT2 receptor (AT2R) has puzzled the scientific community because of its distinct -localization, regulation, signaling pathways, and biological effects separating it clearly from the classical features of the renin......-angiotensin system (RAS) mediated by the angiotensin AT1 receptor. Intensive research over the years has revealed major characteristics of the AT2R as a modulatory player involved in antiproliferation, anti-inflammation, natriuresis, neuroregeneration, and apoptosis, that is, -biological...

  16. Pneumonia Risk and Use of Angiotensin-Converting Enzyme Inhibitors and Angiotensin II Receptor Blockers

    OpenAIRE

    Liu, Chia-Lin; Shau, Wen-Yi; Chang, Chia-Hsuin; Wu, Chi-Shin; Lai, Mei-Shu

    2013-01-01

    Background Recent studies have shown that use of angiotensin-converting enzyme (ACE) inhibitors may decrease pneumonia risk in various populations. We investigated the effect of ACE inhibitors and angiotensin II receptor blockers (ARBs) on pneumonia hospitalization in the general population of Taiwan. Methods We conducted a case-crossover study using the Taiwan Longitudinal Health Insurance Database for the year 2005. Data from patients hospitalized for the first time for pneumonia during 199...

  17. Study of correlation between polymorphism of angiotensin II-1 receptor gene A1166 genotype and complications in atrial fibrillation

    International Nuclear Information System (INIS)

    Objective: To investigate the effect of genetic polymorphism on atrial fibrillation. Methods: Polymerase chain reaction-restrictive fragment length polymorphism(PCR-RFLP) was used to identify and compare the genotype of the location of AT1R gene 1166, and color echo-ultrasound was performed with logistic regression used to analyse the independent risk of various genotypes for atrial fibrillation in 121 patients with atrial fibrillation and 100 controls. Results: (1) Frequency of genotype AC + CC, iso-gene C in atrial fibrillation group was higher than that in control group (P=0.017, 0.013), the risk ratio in patients with genotype AC + CC to develop atrial fibrillation was 3.657 compared with genotype AA (95% CI:1.181∼11.322), and genotype difference as well as systolic pressure were involved in occurrence of overall atrial fibrillation. The OR to develop atrial fibrillation in patients with genotype AC + CC was 4.132 compared with genotype AA (95% CI:1.263∼13.513). (2) There were no significant differences of clinical manifestation (heart failure, cerebral embolism) or ultrasonic parameters among patients with different genotypes (AA vs AC + CC)(P>0.05). Conclusion: People carrying iso-gene C in AT1R gene 1166 were more liable to develop atrial fibrillation, but there were no correlationship with development of complications. (authors)

  18. Antidiabetic mechanisms of angiotensin-converting enzyme inhibitors and angiotensin II receptor antagonists: beyond the renin-angiotensin system

    Czech Academy of Sciences Publication Activity Database

    Kurtz, T. W.; Pravenec, Michal

    2004-01-01

    Roč. 22, č. 12 (2004), s. 2253-2261. ISSN 0263-6352 R&D Projects: GA ČR GA301/03/0751 Grant ostatní: HHMI(US) HHMI55000331 Institutional research plan: CEZ:AV0Z5011922 Keywords : angiotensin II receptors * metabolic syndrome * peroxisome proliferator activated receptors Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.871, year: 2004

  19. Cerebrovascular angiotensin AT1 receptor regulation in cerebral ischemia

    DEFF Research Database (Denmark)

    Edvinsson, Lars

    2008-01-01

    The mechanism behind the positive response to the inhibition of the angiotensin II receptor AT(1) in conjunction with stroke is elusive. Here we demonstrate that cerebrovascular AT(1) receptors show increased expression (upregulation) after cerebral ischemia via enhanced translation. This enhanced...

  20. Addition of Angiotensin Receptor Blockade or Mineralocorticoid Antagonism to Maximal Angiotensin-Converting Enzyme Inhibition in Diabetic Nephropathy

    OpenAIRE

    Mehdi, Uzma F.; Adams-Huet, Beverley; Raskin, Philip; Vega, Gloria L.; Toto, Robert D.

    2009-01-01

    Aldosterone promotes glomerular and tubular sclerosis independent of angiotensin II in animal models of diabetic nephropathy. Most human studies testing the renoprotective benefit of adding an angiotensin receptor blocker or a mineralocorticoid receptor antagonist to a regimen based on inhibition of angiotensin-converting enzyme (ACE) used relatively low doses of ACE inhibitors. Furthermore, these studies did not determine whether antiproteinuric effects were independent of BP lowering. We co...

  1. G-protein coupled receptors of the renin-angiotensin system: new targets against breast cancer?

    OpenAIRE

    Rodrigues-Ferreira, Sylvie; Nahmias, Clara

    2015-01-01

    G-protein coupled receptors (GPCRs) constitute the largest family of membrane receptors, with high potential for drug discovery. These receptors can be activated by a panel of different ligands including ions, hormones, small molecules, and vasoactive peptides. Among those, angiotensins [angiotensin II (AngII) and angiotensin 1–7] are the major biologically active products of the classical and alternative renin-angiotensin system (RAS). These peptides bind and activate three different subtype...

  2. No effect of angiotensin II AT(2)-receptor antagonist PD 123319 on cerebral blood flow autoregulation

    DEFF Research Database (Denmark)

    Estrup, T M; Paulson, O B; Strandgaard, S

    2001-01-01

    Blockade of the renin-angiotensin system with angiotensin-converting enzyme inhibitors (ACE-I) or angiotensin AT1-receptor antagonists shift the limits of autoregulation of cerebral blood flow (CBF) towards lower blood pressure (BP). The role of AT2-receptors in the regulation of the cerebral cir...

  3. Development of polyclonal antibodies against angiotensin type 2 receptors

    OpenAIRE

    1994-01-01

    Murine neuroblastoma N1E-115 cells are a useful system in which to study neuronal angiotensin II (AngII) receptors. N1E-115 cells possess both type 1 (AT1) and type 2 (AT2) AngII receptor subtypes, as does mammalian brain. AT2 receptors in brain or N1E-115 cells can be solubilized in 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate. In the present study, heparin-Sepharose chromatography was used to partially purify solubilized N1E-115 membranes to produce an enriched population of AT...

  4. Molecular determinants of angiotensin II type 1 receptor functional selectivity

    DEFF Research Database (Denmark)

    Aplin, Mark; Bonde, Marie Mi; Hansen, Jakob Lerche

    2008-01-01

    The angiotensin AT(1) receptor is an important pharmacological target in the treatment of cardiovascular disorders, such as hypertension, diabetic nephropathy, cardiac hypertrophy, arrhythmia and failure. Simultaneously, the AT(1) receptor has emerged to be a prominent model for the emerging...... concept that receptors may attain multiple active states with differentiated functional outcomes. Two major signalling pathways are employed by the AT(1) receptor, namely 1) the canonical G(q) protein-dependent activation of inositol phosphate turnover and intracellular calcium release, and 2) G protein......-independent recruitment of beta-arrestin-scaffolded signalling complexes that activate protein kinase pathways. Different states of receptor activation with preference for individual downstream pathways (functional selectivity) have been demonstrated in mutational studies of the AT(1) receptor and by pharmacological...

  5. Angiotensin II receptors and peritoneal dialysis-induced peritoneal fibrosis.

    Science.gov (United States)

    Morinelli, Thomas A; Luttrell, Louis M; Strungs, Erik G; Ullian, Michael E

    2016-08-01

    The vasoactive hormone angiotensin II initiates its major hemodynamic effects through interaction with AT1 receptors, a member of the class of G protein-coupled receptors. Acting through its AT1R, angiotensin II regulates blood pressure and renal salt and water balance. Recent evidence points to additional pathological influences of activation of AT1R, in particular inflammation, fibrosis and atherosclerosis. The transcription factor nuclear factor κB, a key mediator in inflammation and atherosclerosis, can be activated by angiotensin II through a mechanism that may involve arrestin-dependent AT1 receptor internalization. Peritoneal dialysis is a therapeutic modality for treating patients with end-stage kidney disease. The effectiveness of peritoneal dialysis at removing waste from the circulation is compromised over time as a consequence of peritoneal dialysis-induced peritoneal fibrosis. The non-physiological dialysis solution used in peritoneal dialysis, i.e. highly concentrated, hyperosmotic glucose, acidic pH as well as large volumes infused into the peritoneal cavity, contributes to the development of fibrosis. Numerous trials have been conducted altering certain components of the peritoneal dialysis fluid in hopes of preventing or delaying the fibrotic response with limited success. We hypothesize that structural activation of AT1R by hyperosmotic peritoneal dialysis fluid activates the internalization process and subsequent signaling through the transcription factor nuclear factor κB, resulting in the generation of pro-fibrotic/pro-inflammatory mediators producing peritoneal fibrosis. PMID:27167177

  6. Novel roles of nuclear angiotensin receptors and signaling mechanisms.

    Science.gov (United States)

    Gwathmey, TanYa M; Alzayadneh, Ebaa M; Pendergrass, Karl D; Chappell, Mark C

    2012-03-01

    The renin-angiotensin system (RAS) constitutes an important hormonal system in the physiological regulation of blood pressure. The dysregulation of the RAS is considered a major influence in the development and progression of cardiovascular disease and other pathologies. Indeed, experimental and clinical evidence indicates that blockade of this system with angiotensin-converting enzyme (ACE) inhibitors or angiotensin type 1 receptor (AT1R) antagonists is an effective therapy to attenuate hypertension and diabetic renal injury, and to improve heart failure. Originally defined as a circulating system, multiple tissues express a complete RAS, and compelling evidence now favors an intracellular system involved in cell signaling and function. Within the kidney, intracellular expression of the three predominant ANG receptor subtypes is evident in the nuclear compartment. The ANG type 1 receptor (AT1R) is coupled to the generation of reactive oxygen species (ROS) through the activation of phosphoinositol-3 kinase (PI3K) and PKC. In contrast, both ANG type 2 (AT2R) and ANG-(1-7) (AT7R) receptors stimulate nitric oxide (NO) formation, which may involve nuclear endothelial NO synthase (eNOS). Moreover, blockade of either ACE2-the enzyme that converts ANG II to ANG-(1-7)-or the AT7 receptor exacerbates the ANG II-ROS response on renal nuclei. Finally, in a model of fetal programmed hypertension, the nuclear ROS response to ANG II is enhanced, while both AT2 and AT7 stimulation of NO is attenuated, suggesting that an imbalance in the intracellular RAS may contribute to the development of programming events. We conclude that a functional intracellular or nuclear RAS may have important implications in the therapeutic approaches to cardiovascular disease. PMID:22170620

  7. Renal graft failure after addition of an angiotensin II receptor antagonist to an angiotensin-converting enzyme inhibitor

    DEFF Research Database (Denmark)

    Kamper, Anne-Lise; Nielsen, Arne Høj; Baekgaard, Niels;

    2002-01-01

    Combined treatment with an angiotensin-converting enzyme (ACE) inhibitor and an angiotensin II (Ang II) receptor blocker (ARB) has been suggested in order to achieve a more complete blockade of the renin-angiotensin-aldosterone system in cardiovascular and renal disease. The present report...... describes a case of acute renal graft dysfunction following the addition of an ARB to existing ACE inhibition. This unmasked an unknown iliac artery stenosis. The case indicates a possible important role of Ang II generated by non-ACE pathways in this situation....

  8. Angiotensin and mineralocorticoid receptor antagonism attenuates cardiac oxidative stress in angiotensin II-infused rats.

    Science.gov (United States)

    Minas, Jacqueline N; Thorwald, Max A; Conte, Debra; Vázquez-Medina, Jose-Pablo; Nishiyama, Akira; Ortiz, Rudy M

    2015-11-01

    Angiotensin II (Ang II) and aldosterone contribute to hypertension, oxidative stress and cardiovascular damage, but the contributions of aldosterone during Ang II-dependent hypertension are not well defined because of the difficulty to assess each independently. To test the hypothesis that during Ang II infusion, oxidative and nitrosative damage is mediated through both the mineralocorticoid receptor (MR) and angiotensin type 1 receptor (AT1), five groups of Sprague-Dawley rats were studied: (i) control; (ii) Ang II infused (80 ng/min × 28 days); (iii) Ang II + AT1 receptor blocker (ARB; 10 mg losartan/kg per day × 21 days); (iv) Ang II + mineralocorticoid receptor (MR) antagonist (Epl; 100 mg eplerenone/day × 21 days); and (v) Ang II + ARB + Epl (Combo; × 21 days). Both ARB and combination treatments completely alleviated the Ang II-induced hypertension, whereas eplerenone treatment only prolonged the onset of the hypertension. Eplerenone treatment exacerbated the Ang II-mediated increase in plasma and heart aldosterone 2.3- and 1.8-fold, respectively, while ARB treatment reduced both. Chronic MR blockade was sufficient to ameliorate the AT1-mediated increase in oxidative damage. All treatments normalized protein oxidation (nitrotyrosine) levels; however, only ARB and Combo treatments completely reduced lipid peroxidation (4-hydroxynonenal) to control levels. Collectively, these data suggest that receptor signalling, and not the elevated arterial blood pressure, is the principal culprit in the oxidative stress-associated cardiovascular damage in Ang II-dependent hypertension. PMID:26234762

  9. Local and systemic effects of angiotensin receptor blockade in an emphysema mouse model

    OpenAIRE

    Raupach, Tobias; Lüthje, Lars; Kögler, Harald; de Duve, Christian; Schweda, Frank; Hasenfuß, Gerd; Andreas, Stefan

    2011-01-01

    Abstract Objectives COPD with emphysema causes marked neurohumoral activation. Angiotensin II receptors are highly expressed within the lung and interfere with mechanisms involved in the progression of emphysema. This study examined the effects of an angiotensin II receptor blocker (ARB) on pulmonary and systemic manifestations of emphysema in a mouse model. Methods Female NMRI mice received five intratracheal instillations of porcine pancreatic ela...

  10. Increased angiotensin II type 1 receptor expression in temporal arteries from patients with giant cell arteritis

    DEFF Research Database (Denmark)

    Dimitrijevic, Ivan; Malmsjö, Malin; Andersson, Christina; Rissler, Pehr; Edvinsson, Lars

    2009-01-01

    peptide involved in vessel inflammation during atherosclerosis, and angiotensin II receptor inhibitors are effective in preventing atherosclerosis. The present study was performed to elucidate the role of angiotensin type 1 (AT(1)) and type 2 (AT(2)) receptors in GCA. DESIGN: Experimental retrospective...

  11. Angiotensin II receptor alterations during pregnancy in rabbits

    International Nuclear Information System (INIS)

    Despite activation of the renin-angiotensin system during pregnancy, renal and peripheral vascular blood flows increase, and the systemic blood pressure and the pressor response to exogenous angiotensin II (Ang II) fall. Gestational alterations in Ang II receptors could contribute to these changes. Ang II binding parameters were determining utilizing 125I-Ang II in vascular (glomeruli and mesenteric arteries) and nonvascular (adrenal glomerulosa) tissues from 24- to 28-day pregnant rabbits. Comparisons were made utilizing tissues from nonpregnant rabbits. Binding site concentrations (N) and dissociation constants (K/sub d/) were obtained by Scatchard analyses of binding inhibition data. Meclofenamate (M) inhibits prostaglandin synthesis, reduces plasma renin activity, and enhances the pressor response to infused Ang II in pregnant rabbits. Administration of M to pregnant rabbits increased N in glomerular and in mesenteric artery membranes. These data demonstrate that Ang II receptors in glomeruli and mesenteric arteries are down regulated during gestation in rabbits. Elevated endogenous Ang II during pregnancy in rabbits may contribute to the down regulation of vascular Ang II receptors

  12. Activation of the Retinoid X Receptor Modulates Angiotensin II-Induced Smooth Muscle Gene Expression and Inflammation in Vascular Smooth Muscle Cells

    OpenAIRE

    Lehman, Allison M.B.; Montford, John R.; Horita, Henrick; Ostriker, Allison C.; Weiser-Evans, Mary C. M.; Nemenoff, Raphael A.; Furgeson, Seth B.

    2014-01-01

    The retinoid X receptor (RXR) partners with numerous nuclear receptors, such as the peroxisome proliferator activated receptor (PPAR) family, liver X receptors (LXRs), and farnesoid X receptor (FXR). Although each heterodimer can be activated by specific ligands, a subset of these receptors, defined as permissive nuclear receptors, can also be activated by RXR agonists known as rexinoids. Many individual RXR heterodimers have beneficial effects in vascular smooth muscle cells (SMCs). Because ...

  13. New targets for renal interstitial fibrosis: relaxin family peptide receptor 1-angiotensin type 2 receptor heterodimers.

    Science.gov (United States)

    Sasser, Jennifer M

    2014-07-01

    The signal transduction mechanisms involved in the renoprotective effects of relaxin are not well understood. Chow et al. demonstrate that relaxin family peptide receptor 1 (RXFP1) forms heterodimer complexes with the angiotensin type 2 receptor (AT2), even in the absence of ligand, and that these heterodimers are required for relaxin's antifibrotic effects. These findings identify a previously unknown link between relaxin and angiotensin II signaling that could be a potential new target for slowing the progression of fibrotic renal diseases. PMID:24978374

  14. Gene expression profiling following maternal deprivation: Involvement of the brain renin-angiotensin system

    Directory of Open Access Journals (Sweden)

    Wolfgang Wurst

    2009-05-01

    Full Text Available The postnatal development of the mouse is characterized by a stress hyporesponsive period (SHRP, where basal corticosterone levels are low and responsiveness to mild stressors is reduced. Maternal separation is able to disrupt the SHRP and is widely used to model early trauma. In this study we aimed at identifying of brain systems involved in acute and possible long-term effects of maternal separation. We conducted a microarray-based gene expression analysis in the hypothalamic paraventricular nucleus after maternal separation, which revealed 52 differentially regulated genes compared to undisturbed controls, among them are 37 up-regulated and 15 down-regulated genes. One of the prominently up-regulated genes, angiotensinogen, was validated using in-situ hybridization. Angiotensinogen is the precursor of angiotensin II, the main effector of the brain renin-angiotensin system (RAS, which is known to be involved in stress system modulation in adult animals. Using the selective angiotensin type I receptor (AT(1 antagonist candesartan we found strong effects on CRH and GR mRNA expression in the brain a nd ACTH release following maternal separation. AT(1 receptor blockade appears to enhance central effects of maternal separation in the neonate, suggesting a suppressing function of brain RAS during the SHRP. Taken together, our results illustrate the molecular adaptations that occur in the paraventricular nucleus following maternal separation and contribute to identifying signaling cascades that control stress system activity in the neonate.

  15. Determination of the exact molecular requirements for type 1 angiotensin receptor epidermal growth factor receptor transactivation and cardiomyocyte hypertrophy.

    Science.gov (United States)

    Smith, Nicola J; Chan, Hsiu-Wen; Qian, Hongwei; Bourne, Allison M; Hannan, Katherine M; Warner, Fiona J; Ritchie, Rebecca H; Pearson, Richard B; Hannan, Ross D; Thomas, Walter G

    2011-05-01

    Major interest surrounds how angiotensin II triggers cardiac hypertrophy via epidermal growth factor receptor transactivation. G protein-mediated transduction, angiotensin type 1 receptor phosphorylation at tyrosine 319, and β-arrestin-dependent scaffolding have been suggested, yet the mechanism remains controversial. We examined these pathways in the most reductionist model of cardiomyocyte growth, neonatal ventricular cardiomyocytes. Analysis with [(32)P]-labeled cardiomyocytes, wild-type and [Y319A] angiotensin type 1 receptor immunoprecipitation and phosphorimaging, phosphopeptide analysis, and antiphosphotyrosine blotting provided no evidence for tyrosine phosphorylation at Y319 or indeed of the receptor, and mutation of Y319 (to A/F) did not prevent either epidermal growth factor receptor transactivation in COS-7 cells or cardiomyocyte hypertrophy. Instead, we demonstrate that transactivation and cardiomyocyte hypertrophy are completely abrogated by loss of G-protein coupling, whereas a constitutively active angiotensin type 1 receptor mutant was sufficient to trigger transactivation and growth in the absence of ligand. These results were supported by the failure of the β-arrestin-biased ligand SII angiotensin II to transactivate epidermal growth factor receptor or promote hypertrophy, whereas a β-arrestin-uncoupled receptor retained these properties. We also found angiotensin II-mediated cardiomyocyte hypertrophy to be attenuated by a disintegrin and metalloprotease inhibition. Thus, G-protein coupling, and not Y319 phosphorylation or β-arrestin scaffolding, is required for epidermal growth factor receptor transactivation and cardiomyocyte hypertrophy via the angiotensin type 1 receptor. PMID:21383310

  16. New Targets for Renal Interstitial Fibrosis: Relaxin Family Peptide Receptor 1 - Angiotensin Type 2 Receptor Heterodimers

    OpenAIRE

    Sasser, Jennifer M.

    2014-01-01

    Recent findings have shown that relaxin has potent anti-fibrotic effects within the kidney; however, the signal transduction mechanisms involved in the renoprotective effects of relaxin are not well understood. Chow et al demonstrate that the relaxin receptor, RXFP1, forms heterodimer complexes with the angiotensin type 2 receptor, AT2, even in the absence of ligand and that these heterodimer complexes are required for relaxin’s antifibrotic effects. These findings identify a previously unkno...

  17. Renin-Angiotensin System Gene Variants and Type 2 Diabetes Mellitus: Influence of Angiotensinogen

    Directory of Open Access Journals (Sweden)

    Siew Mei Joyce-Tan

    2016-01-01

    Full Text Available Genome-wide association studies (GWAS have been successfully used to call for variants associated with diseases including type 2 diabetes mellitus (T2DM. However, some variants are not included in the GWAS to avoid penalty in multiple hypothetic testing. Thus, candidate gene approach is still useful even at GWAS era. This study attempted to assess whether genetic variations in the renin-angiotensin system (RAS and their gene interactions are associated with T2DM risk. We genotyped 290 T2DM patients and 267 controls using three genes of the RAS, namely, angiotensin converting enzyme (ACE, angiotensinogen (AGT, and angiotensin II type 1 receptor (AGTR1. There were significant differences in allele frequencies between cases and controls for AGT variants (P=0.05 but not for ACE and AGTR1. Haplotype TCG of the AGT was associated with increased risk of T2DM (OR 1.92, 95% CI 1.15–3.20, permuted P=0.012; however, no evidence of significant gene-gene interactions was seen. Nonetheless, our analysis revealed that the associations of the AGT variants with T2DM were independently associated. Thus, this study suggests that genetic variants of the RAS can modestly influence the T2DM risk.

  18. Renin-Angiotensin System Gene Variants and Type 2 Diabetes Mellitus: Influence of Angiotensinogen.

    Science.gov (United States)

    Joyce-Tan, Siew Mei; Zain, Shamsul Mohd; Abdul Sattar, Munavvar Zubaid; Abdullah, Nor Azizan

    2016-01-01

    Genome-wide association studies (GWAS) have been successfully used to call for variants associated with diseases including type 2 diabetes mellitus (T2DM). However, some variants are not included in the GWAS to avoid penalty in multiple hypothetic testing. Thus, candidate gene approach is still useful even at GWAS era. This study attempted to assess whether genetic variations in the renin-angiotensin system (RAS) and their gene interactions are associated with T2DM risk. We genotyped 290 T2DM patients and 267 controls using three genes of the RAS, namely, angiotensin converting enzyme (ACE), angiotensinogen (AGT), and angiotensin II type 1 receptor (AGTR1). There were significant differences in allele frequencies between cases and controls for AGT variants (P = 0.05) but not for ACE and AGTR1. Haplotype TCG of the AGT was associated with increased risk of T2DM (OR 1.92, 95% CI 1.15-3.20, permuted P = 0.012); however, no evidence of significant gene-gene interactions was seen. Nonetheless, our analysis revealed that the associations of the AGT variants with T2DM were independently associated. Thus, this study suggests that genetic variants of the RAS can modestly influence the T2DM risk. PMID:26682227

  19. Angiotensin Type 2 Receptor Stimulation Increases Renal Function in Female, but Not Male, Spontaneously Hypertensive Rats

    DEFF Research Database (Denmark)

    Hilliard, Lucinda M; Chow, Charis L E; Mirabito, Katrina M; Steckelings, Ulrike Muscha; Unger, Thomas; Widdop, Robert E; Denton, Kate M

    2014-01-01

    Accumulating evidence suggests that the protective pathways of the renin-angiotensin system are enhanced in women, including the angiotensin type 2 receptor (AT2R), which mediates vasodilatory and natriuretic effects. To provide insight into the sex-specific ability of pharmacological AT2R stimul...

  20. Renal effects of angiotensin II in the newborn period: role of type 1 and type 2 receptors

    OpenAIRE

    Vinturache, Angela E.; Francine G. Smith

    2016-01-01

    Background Evidence suggests a critical role for the renin-angiotensin system in regulating renal function during postnatal development. However, the physiological relevance of a highly elevated renin-angiotensin system early in life is not well understood, nor which angiotensin receptors might be involved. This study was designed to investigate the roles of angiotensin receptors type 1 (AT1R) and type 2 (AT2R) in regulating glomerular and tubular function during postnatal development. Method...

  1. (Prorenin receptor triggers distinct angiotensin II-independent extracellular matrix remodeling and deterioration of cardiac function.

    Directory of Open Access Journals (Sweden)

    Anne-Mari Moilanen

    Full Text Available BACKGROUND: Activation of the renin-angiotensin-system (RAS plays a key pathophysiological role in heart failure in patients with hypertension and myocardial infarction. However, the function of (prorenin receptor ((PRR is not yet solved. We determined here the direct functional and structural effects of (PRR in the heart. METHODOLOGY/PRINCIPAL FINDINGS: (PRR was overexpressed by using adenovirus-mediated gene delivery in normal adult rat hearts up to 2 weeks. (PRR gene delivery into the anterior wall of the left ventricle decreased ejection fraction (P<0.01, fractional shortening (P<0.01, and intraventricular septum diastolic and systolic thickness, associated with approximately 2-fold increase in left ventricular (PRR protein levels at 2 weeks. To test whether the worsening of cardiac function and structure by (PRR gene overexpression was mediated by angiotensin II (Ang II, we infused an AT(1 receptor blocker losartan via osmotic minipumps. Remarkably, cardiac function deteriorated in losartan-treated (PRR overexpressing animals as well. Intramyocardial (PRR gene delivery also resulted in Ang II-independent activation of extracellular-signal-regulated kinase1/2 phosphorylation and myocardial fibrosis, and the expression of transforming growth factor-β1 and connective tissue growth factor genes. In contrast, activation of heat shock protein 27 phosphorylation and apoptotic cell death by (PRR gene delivery was Ang II-dependent. Finally, (PRR overexpression significantly increased direct protein-protein interaction between (PRR and promyelocytic zinc-finger protein. CONCLUSIONS/SIGNIFICANCE: These results indicate for the first time that (PRR triggers distinct Ang II-independent myocardial fibrosis and deterioration of cardiac function in normal adult heart and identify (PRR as a novel therapeutic target to optimize RAS blockade in failing hearts.

  2. Gene polymorphisms of renin-angiotensin-aldosterone system components and the progression of chronic kidney diseases

    Directory of Open Access Journals (Sweden)

    Agata Kujawa-Szewieczek

    2010-08-01

    Full Text Available The renin-angiotensin-aldosterone system (RAAS plays an important role in the pathogenesis of hypertension as well as cardiovascular diseases and chronic kidney diseases. Among the most frequently studied RAAS gene polymorphisms are the angiotensin-converting enzyme insertion/deletion (I/D, angiotensinogen M235T and angiotensin II receptor type 1 A1166C polymorphisms.A significant correlation was found between the I/D polymorphism and cardiovascular morbidity and mortality rates. However, there was no significant correlation between I/D, M235T, A1166C polymorphism and arterial hypertension. The role of I/D polymorphism in the development and progression of chronic kidney disease is also non-conclusive. However, DD genotype has been identified as relevant for loss of renal function both in patients with IgA nephropathy and in patients of Asian origin with diabetic nephropathy.The relationship between RAAS gene polymorphism and transplanted kidney function has not been confirmed in large prospective and retrospective studies. Conclusion: there is no clear opinion concerning the influence of RAAS genotypes on the prevalence of post-transplant hypertension or erythrocytosis.Although a role of RAAS gene polymorphism in kidney function deterioration could not be ruled out, it is more likely that a variety of genetic and environmental factors influence the progression of chronic kidney diseases.

  3. Cerebral ischemia enhances vascular angiotensin AT1 receptor-mediated contraction in rats

    DEFF Research Database (Denmark)

    Stenman, Emelie; Edvinsson, Lars

    2004-01-01

    MCA occlusion (P<0.05). The angiotensin II type 1 (AT1) receptor antagonists candesartan and losartan abolished the enhanced responses to angiotensin II (P<0.05), whereas the AT2 receptor antagonist PD123319 had no effect. The amount of AT1 receptor mRNA was lower in the occluded MCAs compared with....... These results support a role for AT1 receptors in cerebral ischemia, and we think that AT1 receptors might be a future therapeutic target in ischemic stroke....

  4. Angiotensin receptor blocker telmisartan suppresses renal gluconeogenesis during starvation

    Directory of Open Access Journals (Sweden)

    Tojo A

    2015-02-01

    Full Text Available Akihiro Tojo, Saaya Hatakeyama, Satoshi Kinugasa, Masaomi Nangaku Division of Nephrology and Endocrinology, The University of Tokyo, Tokyo, Japan Abstract: The kidney plays an important role in gluconeogenesis during starvation. To clarify the anti-diabetic action of angiotensin receptor blockers, we examined the effects of telmisartan on the sodium-glucose co-transporters (SGLT and the pathways of renal gluconeogenesis in streptozotocin-induced diabetes mellitus (DM rats. At 4 weeks, the DM rats treated with/without telmisartan for 2 weeks and normal control rats were used for the study after a 24-hour fast. SGLT2 expressed on the brush border membrane of the proximal convoluted tubules increased in the DM rats, but decreased in the rats treated with telmisartan. The expression of restriction enzymes of gluconeogenesis, glucose-6-phosphatase, and phosphoenolpyruvate carboxykinase increased in the proximal tubules in the DM rats, whereas these enzymes decreased in the kidneys of the rats treated with telmisartan. The elevated cytoplasmic glucose-6-phosphate and glucose levels in the kidney of DM rats significantly decreased in those treated with telmisartan, whereas those levels in the liver did not show significant change. Meanwhile, the high plasma glucose levels in the DM rats during the intravenous insulin tolerance tests were ameliorated by telmisartan. The increased fasting plasma glucose levels after 24 hours of starvation in the DM rats thus returned to the control levels by telmisartan treatment. In conclusion, the increased renal SGLT2 expression, elevated renal gluconeogenesis enzymes and extent of insulin-resistance in the DM rats were ameliorated by telmisartan therapy, thus resulting in decreased plasma glucose levels after 24 hours of fasting. Keywords: SGLT2, renal gluconeogenesis, diabetes, angiotensin II

  5. The angiotensin II type 1 receptor antagonist Losartan binds and activates bradykinin B2 receptor signaling

    DEFF Research Database (Denmark)

    Bonde, Marie Mi; Olsen, Kristine Boisen; Erikstrup, Niels;

    2011-01-01

    The angiotensin II type 1 receptor (AT1R) blocker (ARB) Losartan has cardioprotective effects during ischemia-reperfusion injury and inhibits reperfusion arrhythmias -effects that go beyond the benefits of lowering blood pressure. The renin-angiotensin and kallikrein-kinin systems are intricately...... connected and some of the cardioprotective effects of Losartan are abolished by blocking the bradykinin B2 receptor (B2R) signaling. In this study, we investigated the ability of six clinically available ARBs to specifically bind and activate the B2R. First, we investigated their ability to activate...... phosphoinositide (PI) hydrolysis in COS-7 cells transiently expressing the B2R. We found that only Losartan activated the B2R, working as a partial agonist compared to the endogenous ligand bradykinin. This effect was blocked by the B2R antagonist HOE 140. A competitive binding analysis revealed that Losartan does...

  6. A role for the angiotensin type-2 receptor in experimental radiation nephropathy

    International Nuclear Information System (INIS)

    Full text: Irradiation of the kidneys is followed by a well-defined sequence of changes that eventually lead to renal failure. In the rat, blockade of angiotensin II type-1 receptors diminishes and delays the structural and functional changes that occur after kidney irradiation. It has been hypothesized that some of the effects of angiotensin II type-1 blockers are caused by a rise in angiotensin II that stimulates the angiotensin II type-2 receptor. If this hypothesis were applicable to experimental radiation nephropathy, one would expect that blockade of the type-2 receptor by itself would exacerbate radiation nephropathy; and/or that blockade of the type-2 receptor would counteract some or all of the beneficial effects of type-1 receptor blockade. Experiments in the rat radiation nephropathy model failed to support this hypothesis. To the contrary, a type-2 blocker produced a temporary delay in the development of radiation nephropathy when used alone, and it substantially enhanced the prophylactic efficacy of the type-1 blocker. These results imply that both type-1 and type-2 angiotensin receptors need to be blocked to achieve the maximum level of prophylaxis of radiation nephropathy. It is possible that the increased efficacy of the combined blockers is due simply to increased molar levels of angiotensin blockers, so we are determining whether increasing the dose of the type-1 blocker will increase its efficacy. We are also assessing the possibility that the efficacy of angiotensin II blockade can be explained by radiation-induced up-regulation of angiotensin II receptors (type-1, type-2 or total)

  7. Angiotensin AT1-receptor blockers and cerebrovascular protection: do they actually have a cutting edge over angiotensin-converting enzyme inhibitors?

    DEFF Research Database (Denmark)

    Oprisiu-Fournier, Roxana; Faure, Sébastien; Mazouz, Hakim;

    2009-01-01

    is presented to support the hypothesis that antihypertensive drugs that increase angiotensin II formation, such as diuretics, AT1-receptor blockers and dihydropyridines, may have greater brain anti-ischemic effects than antihypertensive drugs that decrease angiotensin II formation, such as beta-blockers...

  8. Renin-angiotensin system genes polymorphism in Egyptians with premature coronary artery disease.

    Science.gov (United States)

    Abd El-Aziz, Tarek A; Hussein, Yousri M; Mohamed, Randa H; Shalaby, Sally M

    2012-05-01

    Genetics polymorphism of the renin-angiotensin system (RAS) affects the pathogenesis of atherosclerosis and associated with coronary artery disease (CAD). We aimed to investigate the association between the RAS genes and premature CAD (PCAD) in Egyptians. 116 patients with PCAD, 114 patients with late onset CAD and 119 controls were included in the study. Angiotensin converting enzyme (ACE), angiotensin II receptor type 1 (ATR1) and angiotensinogen (AGT) genes polymorphisms were analyzed by polymerase chain reaction (PCR). We found that ACE DD, AGT TT and ATR1 CC increased the risk of PCAD by 2.7, 2.8 and 2.86 respectively). Smoking, hypertension, diabetes, total cholesterol, triglycerides and LDL cholesterol were independent risk factors for the development of PCAD. We conclude that the ACE DD, AGT TT and ATR1 CC genotypes may increase the susceptibility of an individual to have PCAD. The coexistence of CAD risk factors with these risky RAS genotypes may lead to the development of PCAD in Egyptian patients. PMID:22387727

  9. Aldosterone synthase C-344T, angiotensin II type 1 receptor A1166C and 11- hydroxysteroid dehydrogenase G534A gene polymorphisms and essential hypertension in the population of Odisha, India

    Indian Academy of Sciences (India)

    Manisha Patnaik; Pallabi Pati; Surendra N. Swain; Manoj K. Mohapatra; Bhagirathi Dwibedi; Shantanu K. Kar; Manoranjan Ranjit

    2014-12-01

    Essential hypertension which accounts 90–95% of the total hypertension cases is affected by both genetic and environmental factors. This study was undertaken to investigate the association of aldosterone synthase C-344T, angiotensin II type I receptor A1166C and 11- hydroxysteroid dehydrogenase type 2 G534A polymorphisms with essential hypertension in the population of Odisha, India. A total of 246 hypertensive subjects (males, 159; females, 87) and 274 normal healthy individuals (males, 158; females, 116) were enrolled in this study based on the inclusion and exclusion criteria. Analysis of genetic and biochemical data revealed that in this population the CT and TT genotypes of aldosterone synthase C-344T polymorphism, frequency of alcohol consumption and aldosterone levels were significantly high among the total as well as male hypertensives, while the AC and CC genotypes of angiotensin II type I receptor A1166C polymorphism were significantly high among the total as well as female hypertensives. High density lipoprotein levels were higher in male hypertensives.

  10. Aldosterone synthase C-344T, angiotensin II type 1 receptor A1166C and 11- hydroxysteroid dehydrogenase G534A gene polymorphisms and essential hypertension in the population of Odisha, India

    Indian Academy of Sciences (India)

    Manisha Patnaik; Pallabi Pati; Surendra N. Swain; Manoj K. Mohapatra; Bhagirathi Dwibedi; Shantanu K. Kar; Manoranjan Ranjit

    2015-06-01

    Essential hypertension which accounts 90–95% of the total hypertension cases is affected by both genetic and environmental factors. This study was undertaken to investigate the association of aldosterone synthase C-344T, angiotensin II type I receptor A1166C and 11- hydroxysteroid dehydrogenase type 2 G534A polymorphisms with essential hypertension in the population of Odisha, India. A total of 246 hypertensive subjects (males, 159; females, 87) and 274 normal healthy individuals (males, 158; females, 116) were enrolled in this study based on the inclusion and exclusion criteria. Analysis of genetic and biochemical data revealed that in this population the CT and TT genotypes of aldosterone synthase C-344T polymorphism, frequency of alcohol consumption and aldosterone levels were significantly high among the total as well as male hypertensives, while the AC and CC genotypes of angiotensin II type I receptor A1166C polymorphism were significantly high among the total as well as female hypertensives. High density lipoprotein levels were higher in male hypertensives.

  11. Angiotensin II receptor blocker attenuates intrarenal renin-angiotensin-system and podocyte injury in rats with myocardial infarction.

    Directory of Open Access Journals (Sweden)

    Zhu-zhi Wen

    Full Text Available The mechanisms and mediators underlying common renal impairment after myocardial infarction (MI are still poorly understood. The present study aimed to test the hypothesis that angiotensin II type 1 receptor blockers (ARBs provides renoprotective effects after MI by preventing augmented intrarenal renin-angiotensin-system (RAS-induced podocyte injury. Sprague-Dawley rats that underwent ligation of their coronary arteries were treated with losartan (20 mg/kg/d or vehicle for 3 or 9 weeks. Renal function, histology and molecular changes were assessed. The current study revealed that MI-induced glomerular podocyte injury was identified by increased immunostaining for desmin and p16(ink4a, decreased immunostaining for Wilms' tumor-1 and podocin mRNA expression, and an induced increase of blood cystatin C at both 3 and 9 weeks. These changes were associated with increased intrarenal angiotensin II levels and enhanced expressions of angiotensinogen mRNA and angiotensin II receptor mRNA and protein. These changes were also associated with decreased levels of insulin-like growth factor (IGF-1 and decreased expressions of IGF-1 receptor (IGF-1R protein and mRNA and phosphorylated(p-Akt protein at 9 weeks, as well as increased expressions of 8-hydroxy-2'-deoxyguanosine at both time points. Treatment with losartan significantly attenuated desmin- and p16(ink4a-positive podocytes, restored podocin mRNA expression, and decreased blood cystatin C levels. Losartan also prevented RAS activation and oxidative stress and restored the IGF-1/IGF-1R/Akt pathway. In conclusion, ARBs prevent the progression of renal impairment after MI via podocyte protection, partially by inhibiting the activation of the local RAS with subsequent enhanced oxidative stress and an inhibited IGF-1/IGF-1R/Akt pathway.

  12. Chromatographic resolution of angiotensin II receptor antagonists (sartans).

    Science.gov (United States)

    Tahir, Muhammad Saqlain; Adnan, Ahmad; Syed, Quratulain

    2016-08-01

    First time a simple, sensitive and unified quantification method has been developed to analyze the complete class of angiotensin II receptor antagonists which are used in the treatment of hypertension either alone or in combination with some other drugs. The most important advantage of developed method was that the eight separate drugs can be determined on a single chromatographic system without modifications in detection wavelength and mobile phase. The drugs were separated on a Purospher Star 4.6mm×25cm, 5μm, C18 column maintained at 40°C with 1mLmin(-1) flow rate using ultra violet detection at 254nm. Good separation (Rs>2.0) was achieved in a short analysis allowing simultaneous determination of all eight sartans. The effect of variation in flow rate, detection wavelength and column oven temperature was also studied. The proposed method was statistically validated in terms of precision, accuracy, linearity, specificity and robustness. The newly developed method proved to be specific, robust and accurate for the quantification of eight sartans in commercial pharmaceutical formulations. PMID:27258943

  13. High Order Gene-Gene Interactions in Eight Single Nucleotide Polymorphisms of Renin-Angiotensin System Genes for Hypertension Association Study

    Directory of Open Access Journals (Sweden)

    Cheng-Hong Yang

    2015-01-01

    Full Text Available Several single nucleotide polymorphisms (SNPs of renin-angiotensin system (RAS genes are associated with hypertension (HT but most of them are focusing on single locus effects. Here, we introduce an unbalanced function based on multifactor dimensionality reduction (MDR for multiloci genotypes to detect high order gene-gene (SNP-SNP interaction in unbalanced cases and controls of HT data. Eight SNPs of three RAS genes (angiotensinogen, AGT; angiotensin-converting enzyme, ACE; angiotensin II type 1 receptor, AT1R in HT and non-HT subjects were included that showed no significant genotype differences. In 2- to 6-locus models of the SNP-SNP interaction, the SNPs of AGT and ACE genes were associated with hypertension (bootstrapping odds ratio [Boot-OR] = 1.972~3.785; 95%, confidence interval (CI 1.26~6.21; P<0.005. In 7- and 8-locus model, SNP A1166C of AT1R gene is joined to improve the maximum Boot-OR values of 4.050 to 4.483; CI = 2.49 to 7.29; P<1.63E−08. In conclusion, the epistasis networks are identified by eight SNP-SNP interaction models. AGT, ACE, and AT1R genes have overall effects with susceptibility to hypertension, where the SNPs of ACE have a mainly hypertension-associated effect and show an interacting effect to SNPs of AGT and AT1R genes.

  14. Functional interactions between 7TM receptors in the renin-angiotensin system--dimerization or crosstalk?

    DEFF Research Database (Denmark)

    Lyngsø, Christina; Erikstrup, Niels; Hansen, Jakob L

    2008-01-01

    The Renin-Angiotensin System (RAS) is important for the regulation of cardiovascular physiology, where it controls blood pressure, and salt- and water homeostasis. Dysregulation of RAS can lead to severe diseases including hypertension, diabetic nephropathy, and cardiac arrhythmia, and -failure....... The importance of the RAS is clearly emphasised by the widespread use of drugs targeting this system in clinical practice. These include, renin inhibitors, angiotensin II receptor type I blockers, and inhibitors of the angiotensin converting enzyme. Some of the important effectors within the system...

  15. Angiotensin receptors in an Australian marsupial, the brushtail possum Trichosurus vulpecula

    Energy Technology Data Exchange (ETDEWEB)

    Sernia, C.; Lello, P.; Thomas, W.G. (Univ. of Queensland, St Lucia (Australia))

    1990-01-01

    In this study, the binding properties of angiotensin receptors were examined in the liver, adrenal, brain, and vascular tissue of the brushtail possum, Trichosurus vulpecula. With 125I-Ile5-angiotensin II as the radioligand, the binding affinity (Ka) and receptor number (R0) were estimated for the liver (Ka = 3.60 +/- 0.31 liters/nmol; R0 = 23.8 +/- 1.30 pmol/g tissue; n = 8) and adrenal (Ka = 1.68 +/- 0.29 liters/nmol; R0 = 1.67 +/- 0.23 pmol/g tissue; n = 8). Specific binding was not found in any of seven areas of the possum brain (n = 6), whereas the expected binding was present in similar areas of the rat brain. Using angiotensin III or the antagonist Sar1-Ala8-angiotensin II as radioligands or changing the composition of the incubation buffer did not alter the outcome. Moreover, the intracerebroventricular injection of 1 and 5 nmol of angiotensin II did not elicit an increase in blood pressure which could be attributed to brain angiotensin II (AII) receptors. Ligand affinities of the adrenal and liver receptors were found to be in the following decreasing order: Val5-AII greater than Ile5-AII = Ile5-AIII greater than Sar1-Ala8-AII greater than Sar1-Gly8-AII greater than Sar1-Leu8-AII greater than Ile5-AI greater than hexapeptide greater than Phe3-Tyr8-AII. The cardiovascular AII receptor was investigated by generating dose-response curves of the pressor activity of Ile5-AII and six AII analogs infused intravenously. It was concluded that liver, adrenal, and vascular AII receptors in the marsupial possum have characteristics similar to those in eutherian mammals. However, the failure to find brain AII receptors raises the possibility that those functions mediated by such receptors in the eutherian brain are absent in the possum and perhaps other marsupials.

  16. Angiotensin receptors in an Australian marsupial, the brushtail possum Trichosurus vulpecula

    International Nuclear Information System (INIS)

    In this study, the binding properties of angiotensin receptors were examined in the liver, adrenal, brain, and vascular tissue of the brushtail possum, Trichosurus vulpecula. With 125I-Ile5-angiotensin II as the radioligand, the binding affinity (Ka) and receptor number (R0) were estimated for the liver (Ka = 3.60 +/- 0.31 liters/nmol; R0 = 23.8 +/- 1.30 pmol/g tissue; n = 8) and adrenal (Ka = 1.68 +/- 0.29 liters/nmol; R0 = 1.67 +/- 0.23 pmol/g tissue; n = 8). Specific binding was not found in any of seven areas of the possum brain (n = 6), whereas the expected binding was present in similar areas of the rat brain. Using angiotensin III or the antagonist Sar1-Ala8-angiotensin II as radioligands or changing the composition of the incubation buffer did not alter the outcome. Moreover, the intracerebroventricular injection of 1 and 5 nmol of angiotensin II did not elicit an increase in blood pressure which could be attributed to brain angiotensin II (AII) receptors. Ligand affinities of the adrenal and liver receptors were found to be in the following decreasing order: Val5-AII greater than Ile5-AII = Ile5-AIII greater than Sar1-Ala8-AII greater than Sar1-Gly8-AII greater than Sar1-Leu8-AII greater than Ile5-AI greater than hexapeptide greater than Phe3-Tyr8-AII. The cardiovascular AII receptor was investigated by generating dose-response curves of the pressor activity of Ile5-AII and six AII analogs infused intravenously. It was concluded that liver, adrenal, and vascular AII receptors in the marsupial possum have characteristics similar to those in eutherian mammals. However, the failure to find brain AII receptors raises the possibility that those functions mediated by such receptors in the eutherian brain are absent in the possum and perhaps other marsupials

  17. POLLUTANT PARTICLES PRODUCE VASOCONSTRICTION AND ENHANCE MAPK SIGNALING VIA ANGIOTENSIN TYPE 1 RECEPTOR

    Science.gov (United States)

    Exposure to particulate matter (PM) is associated with acute cardiovascular mortality and morbidity, but the mechanisms are not entirely clear. In this study, we hypothesized that PM may activate the angiotensin type 1 receptor (AT1R), a G protein-coupled receptor that regulates ...

  18. Renin-angiotensin system gene polymorphisms as risk factors for multiple sclerosis.

    Science.gov (United States)

    Živković, Maja; Kolaković, Ana; Stojković, Ljiljana; Dinčić, Evica; Kostić, Smiljana; Alavantić, Dragan; Stanković, Aleksandra

    2016-04-15

    The components of renin-angiotensin system, such as angiotensin-converting enzyme (ACE), angiotensin II and angiotensin II receptor type 1 and 2 (AT1R and AT2R), are expressed in the central nervous system and leukocytes and proposed to be involved in the inflammation and pathogenesis of multiple sclerosis (MS). ACE I/D, AT1R 1166A/C and AT2R -1332A/G are functional polymorphisms associated with phenotypes of diverse chronic inflammatory diseases. The aim of this study was to investigate the association between ACE I/D, AT1R 1166A/C and AT2R -1332A/G gene polymorphisms and MS in Serbian population. A total of 470 MS patients and 478 controls participated in the study. Allele-specific polymerase chain reaction (PCR) was performed for genotyping of the ACE polymorphism. The AT1R and AT2R genotyping was done by duplex PCR and restriction fragment length polymorphism analysis. Both ACE homozygotes, II and DD, were significantly overrepresented in MS patients, compared to controls (χ(2) test p=0.03). Neither genotype nor allele frequencies of AT1R 1166A/C polymorphism were significantly different between patients and controls. Significant overrepresentation of AT2R -1332 AA genotype in female patients, compared to female controls, was detected (OR=1.67, 95%CI=1.13-2.49, χ(2) test p=0.01), suggesting that this genotype could be a gender-specific genetic risk factor for MS. PMID:27000216

  19. Promyelocytic leukemia zinc finger protein activates GATA4 transcription and mediates cardiac hypertrophic signaling from angiotensin II receptor 2.

    Directory of Open Access Journals (Sweden)

    Ning Wang

    Full Text Available BACKGROUND: Pressure overload and prolonged angiotensin II (Ang II infusion elicit cardiac hypertrophy in Ang II receptor 1 (AT(1 null mouse, whereas Ang II receptor 2 (AT(2 gene deletion abolishes the hypertrophic response. The roles and signals of the cardiac AT(2 receptor still remain unsettled. Promyelocytic leukemia zinc finger protein (PLZF was shown to bind to the AT(2 receptor and transmit the hypertrophic signal. Using PLZF knockout mice we directed our studies on the function of PLZF concerning the cardiac specific transcription factor GATA4, and GATA4 targets. METHODOLOGY AND PRINCIPAL FINDINGS: PLZF knockout and age-matched wild-type (WT mice were treated with Ang II, infused at a rate of 4.2 ng·kg(-1·min(-1 for 3 weeks. Ang II elevated systolic blood pressure to comparable levels in PLZF knockout and WT mice (140 mmHg. WT mice developed prominent cardiac hypertrophy and fibrosis after Ang II infusion. In contrast, there was no obvious cardiac hypertrophy or fibrosis in PLZF knockout mice. An AT(2 receptor blocker given to Ang II-infused wild type mice prevented hypertrophy, verifying the role of AT(2 receptor for cardiac hypertrophy. Chromatin immunoprecipitation and electrophoretic mobility shift assay showed that PLZF bound to the GATA4 gene regulatory region. A Luciferase assay verified that PLZF up-regulated GATA4 gene expression and the absence of PLZF expression in vivo produced a corresponding repression of GATA4 protein. CONCLUSIONS: PLZF is an important AT(2 receptor binding protein in mediating Ang II induced cardiac hypertrophy through an AT(2 receptor-dependent signal pathway. The angiotensin II-AT(2-PLZF-GATA4 signal may further augment Ang II induced pathological effects on cardiomyocytes.

  20. Angiotensin converting enzyme gene polymorphism in familial hypertrophic cardiomyopathy patients

    Energy Technology Data Exchange (ETDEWEB)

    Yu, B; Peric, S.; Ross, D. [Royal Prince Alfred Hospital, Campertown (Australia)] [and others

    1994-09-01

    An insertion/deletion (I/D) polymorphism of the angiotensin I converting enzyme (ACE) gene is a useful predictor of human plasma ACE levels. ACE levels tend to be lowest in subjects with ACE genotype DD and intermediate in subjects with ACE genotype ID. Angiotensin II (Ang II) as a product of ACE is a cardiac growth factor and produces a marked hypertrophy of the chick myocyte in cell culture. Rat experiments also suggest that a small dose of ACE inhibitor that does not affect the afterload results in prevention or regression of cardiac hypertrophy. In order to study the relationship of ACE and the severity of hypertrophy, the ACE genotype has been determined in 28 patients with a clinical diagnosis of familial hypertrophic cardiomyopathy (FHC) and 51 normal subjects. The respective frequencies of I and D alleles were: 0.52 and 0.48 (in FHC patients) and 0.44 and 0.56 (in the normal controls). There was no significant difference in the allele frequencies between FHC and normal subjects ({chi}{sup 2}=0.023, p>0.05). The II, ID, and DD genotypes were present in 7, 15, and 6 FHC patients, respectively. The averages of maximal thickness of the interventricular septum measured by echocardiography or at autopsy were 18 {plus_minus}3, 19{plus_minus}4, and 19{plus_minus}3 mm in II, ID and DD genotypes, respectively. The ACE gene polymorphism did not correlate with the severity of left ventricular hypertrophy in FHC patients (r{sub s}=0.231, p>0.05). These results do not necessarily exclude the possible effect of Ang II on the hypertrophy since the latter may be produced through the action of chymase in the human ventricles. However, ACE gene polymorphism is not a useful predictor of the severity of myocardial hypertrophy in FHC patients.

  1. Biased Signaling of the Angiotensin II Type 1 Receptor Can Be Mediated through Distinct Mechanisms

    OpenAIRE

    Bonde, Marie Mi; Hansen, Jonas Tind; Sanni, Samra Joke; Haunsø, Stig; Gammeltoft, Steen; Lyngsø, Christina; Hansen, Jakob Lerche

    2010-01-01

    Background Seven transmembrane receptors (7TMRs) can adopt different active conformations facilitating a selective activation of either G protein or β-arrestin-dependent signaling pathways. This represents an opportunity for development of novel therapeutics targeting selective biological effects of a given receptor. Several studies on pathway separation have been performed, many of these on the Angiotensin II type 1 receptor (AT1R). It has been shown that certain ligands or mutations facilit...

  2. Angiotensin II AT1 receptor blockers as treatments for inflammatory brain disorders

    OpenAIRE

    Saavedra, Juan M.

    2012-01-01

    The effects of brain AngII (angiotensin II) depend on AT1 receptor (AngII type 1 receptor) stimulation and include regulation of cerebrovascular flow, autonomic and hormonal systems, stress, innate immune response and behaviour. Excessive brain AT1 receptor activity associates with hypertension and heart failure, brain ischaemia, abnormal stress responses, blood–brain barrier breakdown and inflammation. These are risk factors leading to neuronal injury, the incidence and progression of neurod...

  3. Addition of Angiotensin Receptor Blockade or Mineralocorticoid Antagonism to Maximal Angiotensin-Converting Enzyme Inhibition in Diabetic Nephropathy

    Science.gov (United States)

    Mehdi, Uzma F.; Adams-Huet, Beverley; Raskin, Philip; Vega, Gloria L.

    2009-01-01

    Aldosterone promotes glomerular and tubular sclerosis independent of angiotensin II in animal models of diabetic nephropathy. Most human studies testing the renoprotective benefit of adding an angiotensin receptor blocker or a mineralocorticoid receptor antagonist to a regimen based on inhibition of angiotensin-converting enzyme (ACE) used relatively low doses of ACE inhibitors. Furthermore, these studies did not determine whether antiproteinuric effects were independent of BP lowering. We conducted a double-blind, placebo-controlled trial in 81 patients with diabetes, hypertension, and albuminuria (urine albumin-to-creatinine ratio ≥300 mg/g) who all received lisinopril (80 mg once daily). We randomly assigned the patients to placebo, losartan (100 mg daily), or spironolactone (25 mg daily) for 48 wk. We obtained blood and urine albumin, urea, creatinine, electrolytes, A1c, and ambulatory BP at baseline, 24, and 48 wk. Compared with placebo, the urine albumin-to-creatinine ratio decreased by 34.0% (95% CI, −51.0%, −11.2%, P = 0.007) in the group assigned to spironolactone and by 16.8% (95% CI, −37.3%, +10.5%, P = 0.20) in the group assigned to losartan. Clinic and ambulatory BP, creatinine clearance, sodium and protein intake, and glycemic control did not differ between groups. Serum potassium level was significantly higher with the addition of either spironolactone or losartan. In conclusion, the addition of spironolactone, but not losartan, to a regimen including maximal ACE inhibition affords greater renoprotection in diabetic nephropathy despite a similar effect on BP. These results support the need to conduct a long-term, large-scale, renal failure outcomes trial. PMID:19926893

  4. Effects of the angiotensin-receptor blocker telmisartan on cardiovascular events in high-risk patients intolerant to angiotensin-converting enzyme inhibitors: a randomised controlled trial

    DEFF Research Database (Denmark)

    NN, NN; Yusuf, S; Teo, K;

    2008-01-01

    BACKGROUND: Angiotensin-converting enzyme (ACE) inhibitors reduce major cardiovascular events, but are not tolerated by about 20% of patients. We therefore assessed whether the angiotensin-receptor blocker telmisartan would be effective in patients intolerant to ACE inhibitors with cardiovascular...... group). INTERPRETATION: Telmisartan was well tolerated in patients unable to tolerate ACE inhibitors. Although the drug had no significant effect on the primary outcome of this study, which included hospitalisations for heart failure, it modestly reduced the risk of the composite outcome...

  5. INHIBITION OF KIDNEY DISORDERS IN CARDIOVASCULAR DISEASES: THE ROLE OF ANGIOTENSIN II RECEPTOR BLOCKERS

    Directory of Open Access Journals (Sweden)

    V. V. Fomin

    2016-01-01

    Full Text Available Mechanisms of renal disorders in cardiovascular diseases are presented. The main of these mechanisms is an endothelium dysfunction. It is related with some factors: arterial hypertension, insulin resistance syndrome, diabetes type 2, dyslipidemia, obesity. Approaches to prevention of kidney disorder and cardiovascular complications are discussed with focus on usage of angiotensin II receptor blockers.

  6. Role of angiotensin receptor blockers in patients with left ventricular dysfunction : lessons from CHARM and VALIANT

    NARCIS (Netherlands)

    Voors, AA; van Veldhuisen, DJ

    2004-01-01

    The role of angiotensin receptor blockers (ARBs) in patients with left ventricular dysfunction has changed after the VALIANT and CHARM trials. CHARM proved that candesartan is a good alternative for patients with chronic heart failure who cannot tolerate ACE-inhibitors. Moreover, VALIANT demonstrate

  7. Effect of angiotensin Ⅱ and angiotensin Ⅱ type 1 receptor antagonist on the proliferation,contraction and collagen synthesis in rat hepatic stellate cells

    Institute of Scientific and Technical Information of China (English)

    LIU Jun; GONG Hao; ZHANG Zhong-tao; WANG Yu

    2008-01-01

    Background Angiotensin Ⅱ(Ang Ⅱ)is a very important vasoactive peptide that acts upon hepatic stellate cells(HSCs),which are major effector cells in hepatic cirrhosis and portal hypertension.The present study was aimed to investigate the effects of Ang Ⅱ and angiotensin Ⅱ type 1 receptor antagonist(AT1RA)on the proliferation,contraction and collagen synthesis in HSCs.Methods HSC-T6 rat hepatic stellate cell Iine was studied.The proliferation of the HSC cells was evaluated by MTT colorimetric assay while HSC DNA synthesis was measured by3 H-thymidine incorporation.The effects of angiotensin Ⅱ and AT1 RA on HSCs contraction were studied by analVSIs of the contraction of the collagen Iattice.CelI culture media were analyzed by RT-PCR to detect secretion of collagen Ⅰ(Col Ⅰ),collagen Ⅲ(Col Ⅲ)and transforming growth factor β1 (TGF-β1)by enzyme Iinked Immunosorbent assay.HSC was harvested to measure collagen Ⅰ,collagen Ⅲ and tissue inhibitor of metalloproteinase-1(TIMP-1)mRNA expression.Results Ang Ⅱ((1 x10-10-1×10-4)mol/L)stimulated DNA synthesis and proliferation in HSCs compared with untreated control cells.AT1 RA inhibited angiotensin Ⅱ induced proliferation of HSCs.A Iinear increase in the contractive area of collagen lattice correlated with the concentration of angiotensin Ⅱ(1×10-9-1×10-5mol/L)and with time over 48 hours.ATlRA blocks angiotensin Ⅱ induced contraction of collagen Iattice.Coll,Col Ⅲ and TGF-β1 levels of the Ang Ⅱ group were higher than those of control group and this increase was downregulated by AT1RA.The mRNA expressions of ColⅠ,CoI Ⅲ and TIMP-1 were higher in HSCs from the Ang Ⅱ group than the control group and downregulated by AT1RA.Conclusions Angiotensin Ⅱ increased DNA synthesis and proliferation of HSCs in a dose-dependent manner,stimulated the contraction of HSCs dose-and time-dependently.Angiotensin also promoted excretion of Col Ⅰ,ColⅢand TGF-β1 Ievels and stimulated Col Ⅰ,Col Ⅲ and

  8. Angiotensin II increases gene expression after selective intra-arterial adenovirus delivery in a rabbit model assessed using in vivo SSTR2-based reporter imaging

    OpenAIRE

    Singh, Sheela P.; Ravoori, Murali K.; Dixon, Katherine A.; Han, Lin; Gupta, Sanjay; Uthamanthil, Rajesh; Wright, Kenneth C; Kundra, Vikas

    2016-01-01

    Background Gene therapy has been hampered by low expression upon in vivo delivery. Using a somatostatin receptor type 2 (SSTR2)-based reporter, we assessed whether angiotensin II (AII) can improve gene expression by adenovirus upon intra-arterial (IA) delivery in a large animal model. Methods A SSTR2-based reporter that can be imaged by a clinically approved radiopharmaceutical was used to assess gene expression. Eight rabbits bearing VX2 tumors in each thigh were randomly injected IA with ad...

  9. Angiotensin II Receptors Modulate Muscle Microvascular and Metabolic Responses to Insulin In Vivo

    OpenAIRE

    Chai, Weidong; Wang, WenHui; Dong, Zhenhua; Cao, Wenhong; Liu, Zhenqi

    2011-01-01

    OBJECTIVE Angiotensin (ANG) II interacts with insulin-signaling pathways to regulate insulin sensitivity. The type 1 (AT1R) and type 2 (AT2R) receptors reciprocally regulate basal perfusion of muscle microvasculature. Unopposed AT2R activity increases muscle microvascular blood volume (MBV) and glucose extraction, whereas unopposed AT1R activity decreases both. The current study examined whether ANG II receptors modulate muscle insulin delivery and sensitivity. RESEARCH DESIGN AND METHODS Ove...

  10. Prejunctional angiotensin II receptors. Facilitation of norepinephrine release in the human forearm.

    OpenAIRE

    Clemson, B; L. Gaul; Gubin, S S; Campsey, D M; MCCONVILLE, J; Nussberger, J.; Zelis, R

    1994-01-01

    To determine if peripheral angiotensin II (Ang II) prejunctional receptors facilitating NE release exist in humans, we used [3H]NE kinetic methodology to measure forearm NE spillover during intrabrachial arterial Ang II infusions in eight normal male subjects. We used the following protocol to optimize conditions for demonstrating these receptors: (a) lower body negative pressure (-15 mmHg) to increase sympathetic nerve activity to skeletal muscle; and (b) intraarterial nitroprusside to maint...

  11. Different angiotensin receptor blockers and incidence of diabetes: a nationwide population-based cohort study

    OpenAIRE

    Chang, Chia-Hsuin; Chang, Yi-Cheng; Wu, Li-Chiu; Lin, Jou-Wei; Chuang, Lee-Ming; Lai, Mei-Shu

    2014-01-01

    Background Angiotensin receptor blockers (ARBs) have been shown to exert various peroxisome proliferator-activated receptor gamma (PPARγ) binding activities and insulin-sensitizing effects. The objective of this study was to investigate the association of different ARBs with new-onset diabetes mellitus. Methods In the respective cohort, a total of 492,530 subjects who initiated ARB treatment between January 2004 and December 2009 were identified from Taiwan National Health Insurance Database....

  12. Cardiovascular risk reduction in hypertension: angiotensin-converting enzyme inhibitors, angiotensin receptor blockers. Where are we up to?

    Science.gov (United States)

    Sindone, A; Erlich, J; Lee, C; Newman, H; Suranyi, M; Roger, S D

    2016-03-01

    Previously, management of hypertension has concentrated on lowering elevated blood pressure. However, the target has shifted to reducing absolute cardiovascular (CV) risk. It is estimated that two in three Australian adults have three or more CV risk factors at the same time. Moderate reductions in several risk factors can, therefore, be more effective than major reductions in one. When managing hypertension, therapy should be focused on medications with the strongest evidence for CV event reduction, substituting alternatives only when a primary choice is not appropriate. Hypertension management guidelines categorise angiotensin-converting enzyme inhibitors (ACEI) and angiotensin receptor blockers (ARB) interchangeably as first-line treatments in uncomplicated hypertension. These medications have different mechanisms of action and quite different evidence bases. They are not interchangeable and their prescription should be based on clinical evidence. Despite this, currently ARB prescriptions are increasing at a higher rate than those for ACEI and other antihypertensive classes. Evidence that ACEI therapy prevents CV events and death, in patients with coronary artery disease or multiple CV risk factors, emerged from the European trial on reduction of cardiac events with perindopril in stable coronary artery disease (EUROPA) and Heart Outcomes Prevention Evaluation (HOPE) trials respectively. The consistent benefit has been demonstrated in meta-analyses. The clinical trial data for ARB are less consistent, particularly regarding CV outcomes and mortality benefit. The evidence supports the use of ACEI (Class 1a) compared with ARB despite current prescribing trends. PMID:26968600

  13. No significant effect of angiotensin II receptor blockade on intermediate cardiovascular end points in hemodialysis patients

    DEFF Research Database (Denmark)

    Peters, Christian D; Kjaergaard, Krista D; Jensen, Jens D;

    2014-01-01

    patients in a double-blind randomized placebo-controlled 1-year intervention trial using a predefined systolic blood pressure target of 140 mm Hg (SAFIR study). Each group of 41 patients did not differ in terms of age, blood pressure, comorbidity, antihypertensive treatment, dialysis parameters, and......Agents blocking the renin-angiotensin-aldosterone system are frequently used in patients with end-stage renal disease, but whether they exert beneficial cardiovascular effects is unclear. Here the long-term effects of the angiotensin II receptor blocker, irbesartan, were studied in hemodialysis...

  14. Estimation of the number of angiotensin II AT1 receptors in rat kidney afferent and efferent arterioles

    DEFF Research Database (Denmark)

    Razga, Zsolt; Nyengaard, Jens Randel

    2007-01-01

    OBJECTIVE: To examine the effects of the renin-angiotensin system (RAS) on renal arterioles to determine the association between the distribution of angiotensin II AT1 receptors and the morphologic and physiologic heterogeneity of renal arterioles. STUDY DESIGN: To estimate the number of angioten...

  15. Effects of angiotensin II receptor blockade on cerebral, cardiovascular, counter-regulatory, and symptomatic responses during hypoglycaemia in patients with type 1 diabetes

    DEFF Research Database (Denmark)

    Færch, Louise H; Thorsteinsson, Birger; Tarnow, Lise;

    2015-01-01

    INTRODUCTION: High spontaneous activity of the renin-angiotensin system (RAS) results in more pronounced cognitive impairment and more prolonged QTc interval during hypoglycaemia in type 1 diabetes. We tested whether angiotensin II receptor blockade improves cerebral and cardiovascular function...

  16. Arterial stiffness in insulin resistance: The role of nitric oxide and angiotensin II receptors

    Directory of Open Access Journals (Sweden)

    Divina G Brillante

    2008-12-01

    Full Text Available Divina G Brillante1, Anthony J O’Sullivan1, Laurence G Howes21St. George Clinical School, University of New South Wales, Kogarah, NSW, Australia; 2Department of Pharmacology and Therapeutics and Department of Cardiology, Griffith and Bond University, Gold Coast Hospital, Southport, QLD, AustraliaAbstract: The insulin resistance syndrome (INSR is associated with increased cardiovascular risk, and affects up to 25% of the Australian population aged >20 years. Increased arterial stiffness has been proposed as a common pathway by which INSR leads to increased cardiovascular risk. We have reviewed the role of nitric oxide (NO and angiotensin II receptors in the modulation of arterial stiffness in the setting of insulin resistance. There is emerging evidence that early stages of INSR may be characterized by increased basal nitric oxide activity and increased activity of non-NO vasodilators such as endothelial derived hyperpolarization factor (EDHF which is manifest by reduced arterial stiffness. Depletion of NO or ineffectiveness of NO mediated vasodilator mechanisms associated with the progression of INSR to type 2 diabetes may result in increased arterial stiffness, which predicts the development of cardiovascular disease. Thus in the early stages of INSR, increased NO and EDHF activity may represent compensatory mechanisms to early vascular damage. The renin-angiotensin system is activated in diseased vascular beds, with up regulation of the two known angiotensin II receptors: the angiotensin II type 1 receptor (AT1R and the angiotensin II type 2 receptor (AT2R. Increased AT1R mediated activity in the vasculature is central to the development of increased arterial stiffness and is enhanced in INSR states. AT2R activity is increased in early in INSR and may contribute to the apparent increase in basal NO activity. AT1R blockade may therefore be valuable treatment for early INSR as antagonism of AT1 receptors would allow angiotensin II to act

  17. Severe hepatic encephalopathy in a patient with liver cirrhosis after administration of angiotensin-converting enzyme inhibitor/angiotensin II receptor blocker combination therapy: a case report

    Directory of Open Access Journals (Sweden)

    Podda Mauro

    2010-05-01

    Full Text Available Abstract Introduction A combination therapy of angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers has been used to control proteinuria, following initial demonstration of its efficacy. However, recently concerns about the safety of this therapy have emerged, prompting several authors to urge for caution in its use. In the following case report, we describe the occurrence of a serious and unexpected adverse drug reaction after administration of a combination of angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers to a patient with nephrotic syndrome and liver cirrhosis with severe portal hypertension. Case presentation We administered this combination therapy to a 40-year-old Caucasian man with liver cirrhosis in our Hepatology Clinic, given the concomitant presence of glomerulopathy associated with severe proteinuria. While the administration of one single drug appeared to be well-tolerated, our patient developed severe acute encephalopathy after the addition of the second one. Discontinuation of the therapy led to the disappearance of the side-effect. A tentative rechallenge with the same drug combination led to a second episode of acute severe encephalopathy. Conclusion We speculate that this adverse reaction may be directly related to the effect of angiotensin II on the excretion of blood ammonia. Therefore, we suggest that patients with liver cirrhosis and portal hypertension are at risk of developing clinically relevant encephalopathy when angiotensin-converting enzyme inhibitor and angiotensin II receptor blocker combination therapy is administered, thus indicating the need for a careful clinical follow-up. In addition, the incidence of this serious side-effect should be rigorously evaluated in all patients with liver cirrhosis administered with this common treatment combination.

  18. A systematic review of the role of renin angiotensin aldosterone system genes in diabetes mellitus, diabetic retinopathy and diabetic neuropathy

    Directory of Open Access Journals (Sweden)

    Zohreh Rahimi

    2014-01-01

    Full Text Available Background: The renin angiotensin aldosterone system (RAAS plays a vital role in regulating glucose metabolism and blood pressure, electrolyte and fluid homeostasis. The aim of this systematic review is to assess the association of the RAAS genes with diabetes mellitus (DM and its complications of retinopathy, neuropathy and cardiovascular disease (CVD. Materials and Methods: The relevant English-language studies were identified using the key words of DM, type 1 diabetes mellitus (T1DM, T2DM, renin angiotensin aldosterone polymorphisms or genotypes and RAAS from the search engines of MEDLINE/PubMed, and Scopus from January 1, 1995 to July 30, 2014. Inclusion criteria for selecting relevant studies were reporting the role of RAAS gene variants in the pathogenesis of T1DM or T2DM, diabetic retinopathy (DR, diabetic neuropathy and cardiovascular complication of DM. Results: The reviewers identified 204 studies of which 73 were eligible for inclusion in the present systematic review. The review indicates the angiotensinogen (AGT M235T polymorphism might not affect the risk of DM. The role of angiotensin converting enzyme insertion/deletion (ACE I/D and angiotensin II type 1 receptor gene (AT1R A1166C polymorphisms in the pathogenesis of DM could not be established. Studies indicate the absence of an association between three polymorphisms of AGT M235T, ACE I/D and AT1R A1166C and DR in DM patients. A protective role for ACE II genotype against diabetic peripheral neuropathy has been suggested. Also, the ACE I/D polymorphism might be associated with the risk of CVD in DM patients. Conclusion: More studies with adequate sample size that investigate the influence of all RAAS gene variants together on the risk of DM and its complications are necessary to provide a more clear picture of the RAAS genes polymorphisms involvement in the pathogenesis of DM and its complications.

  19. The human angiotensin AT(1) receptor supports G protein-independent extracellular signal-regulated kinase 1/2 activation and cellular proliferation

    DEFF Research Database (Denmark)

    Hansen, Jakob Lerche; Aplin, Mark; Hansen, Jonas Tind; Christensen, Gitte Lund; Bonde, Marie Mi; Schneider, Mikael; Haunsø, Stig; Schiffer, Hans H; Burstein, Ethan S; Weiner, David M; Sheikh, Søren P

    AT(1) receptor signalling is illustrated by the common use of angiotensin AT(1) receptor-inverse agonists in clinical practice. It is well established that rodent orthologues of the angiotensin AT(1) receptor can selectively signal through G protein-dependent and -independent mechanisms in......(1) receptor actions. However, it is currently unknown whether the human angiotensin AT(1) receptor can signal through G protein-independent mechanisms - and if so, what the physiological impact of such signalling is. We have performed a detailed pharmacological analysis of the human angiotensin AT(1......) receptor using a battery of angiotensin analogues and registered drugs targeting this receptor. We show that the human angiotensin AT(1) receptor signals directly through G protein-independent pathways and supports NIH3T3 cellular proliferation. The realization of G protein-independent signalling by the...

  20. Effect of angiotensin receptor blockade on endothelial function: focus on olmesartan medoxomil

    Directory of Open Access Journals (Sweden)

    Carlos Ferrario

    2009-03-01

    Full Text Available Carlos FerrarioHypertension and Vascular Disease Center, Wake Forest University School of Medicine, Winston-Salem, NC, USAAbstract: Endothelial dysfunction is the common link between cardiovascular disease risk factors and the earliest event in the cascade of incidents that results in target organ damage. Angiotensin II, the terminal pressor effector arm of the renin-angiotensin-aldosterone system, increases blood pressure (BP by vasoconstriction and sodium and fluid retention, and has a pro-oxidative action that induces endothelial dysfunction and contributes to vascular remodeling. Angiotensin receptor blockers (ARBs reduce BP and morbidity and mortality in patients with hypertension, ventricular hypertrophy, diabetes mellitus, and renal disease. Olmesartan medoxomil is a long-acting, well-tolerated, effective ARB that prevents or reverses endothelial dysfunction in animal models of atherosclerosis, hypertension, diabetes, nephropathy, and retinopathy. Olmesartan medoxomil, a prodrug of olmesartan approved for the treatment of hypertension, has been shown to ameliorate endothelial dysfunction in patients with hypertension or diabetes. In randomized studies, the drug reduces vascular inflammation and the volume of large atherosclerotic plaques, increases the number of regenerative endothelial progenitor cells in the peripheral circulation, improves endothelium-dependent relaxation, and restores the normal resistance vessel morphology. Importantly, the impact of olmesartan medoxomil on endothelial dysfunction is thought to be independent of BP lowering.Keywords: endothelial dysfunction, angiotensin receptor blocker, olmesartan medoxomil, hypertension, atherosclerosis 

  1. Activation of the Cardiac Renin-Angiotensin System in High Oxygen-Exposed Newborn Rats: Angiotensin Receptor Blockade Prevents the Developmental Programming of Cardiac Dysfunction.

    Science.gov (United States)

    Bertagnolli, Mariane; Dios, Anne; Béland-Bonenfant, Sarah; Gascon, Gabrielle; Sutherland, Megan; Lukaszewski, Marie-Amélie; Cloutier, Anik; Paradis, Pierre; Schiffrin, Ernesto L; Nuyt, Anne Monique

    2016-04-01

    Newborn rats exposed to high oxygen (O2), mimicking preterm birth-related neonatal stress, develop later in life cardiac hypertrophy, dysfunction, fibrosis, and activation of the renin-angiotensin system. Cardiac renin-angiotensin system activation in O2-exposed adult rats is characterized by an imbalance in angiotensin (Ang) receptors type 1/2 (AT1/2), with prevailing AT1 expression. To study the role of renin-angiotensin system in the developmental programming of cardiac dysfunction, we assessed Ang receptor expression during neonatal high O2 exposure and whether AT1 receptor blockade prevents cardiac alterations in early adulthood. Sprague-Dawley newborn rats were kept with their mother in 80% O2 or room air (control) from days 3 to 10 (P3-P10) of life. Losartan or water was administered by gavage from P8 to P10 (n=9/group). Rats were studied at P3 (before O2 exposure), P5, P10 (end of O2), and P28. Losartan treatment had no impact on growth or kidney development. AT1 and Ang type 2 receptors were upregulated in the left ventricle by high O2 exposure (P5 and P10), which was prevented by Losartan treatment at P10. Losartan prevented the cardiac AT1/2 imbalance at P28. Losartan decreased cardiac hypertrophy and fibrosis and improved left ventricle fraction of shortening in P28 O2-exposed rats, which was associated with decreased oxidation of calcium/calmodulin-dependent protein kinase II, inhibition of the transforming growth factor-β/SMAD3 pathway, and upregulation of cardiac angiotensin-converting enzyme 2. In conclusion, short-term Ang II blockade during neonatal high O2 prevents the development of cardiac alterations later in life in rats. These findings highlight the key role of neonatal renin-angiotensin system activation in the developmental programming of cardiac dysfunction induced by deleterious neonatal conditions. PMID:26857347

  2. Use of angiotensin receptor blockers and risk of dementia in a predominantly male population: prospective cohort analysis

    OpenAIRE

    Li, Nien-Chen; Lee, Austin; Whitmer, Rachel A.; Kivipelto, Miia; Lawler, Elizabeth; Kazis, Lewis E; Wolozin, Benjamin

    2010-01-01

    Objective To investigate whether angiotensin receptor blockers protect against Alzheimer’s disease and dementia or reduce the progression of both diseases. Design Prospective cohort analysis. Setting Administrative database of the US Veteran Affairs, 2002-6. Population 819 491 predominantly male participants (98%) aged 65 or more with cardiovascular disease. Main outcome measures Time to incident Alzheimer’s disease or dementia in three cohorts (angiotensin receptor blockers, lisinopril, and ...

  3. Purification and characterization of angiotensin II AT2 receptors from neonatal rat kidney.

    OpenAIRE

    Ciuffo, G M; Heemskerk, F M; Saavedra, J M

    1993-01-01

    Angiotensin II (Ang II) AT2 receptors were purified 40,000-fold to a nearly homogeneous state after solubilization from neonatal rat kidney membranes with 3-[(3-cholamidopropyl)dimethylammonio]-2-hydroxy-1-propane-sulfonic acid. Comparable IC50 values for the soluble extract (0.32 nM) and membranes (0.31 nM) were obtained by competition curves with 125I-labeled CGP42112, a selective AT2 ligand. Binding to AT2 receptors in the soluble extract was not sensitive to dithiothreitol. AT2 receptors ...

  4. Angiotensin II Type 1 Receptor Signaling Regulates Feeding Behavior through Anorexigenic Corticotropin-releasing Hormone in Hypothalamus*

    OpenAIRE

    Yamamoto, Rie; Akazawa, Hiroshi; Fujihara, Hiroaki; Ozasa, Yukako; Yasuda, Noritaka; Ito, Kaoru; Kudo, Yoko; Qin, Yingjie; Ueta, Yoichi; Komuro, Issei

    2011-01-01

    The activation of renin-angiotensin system contributes to the development of metabolic syndrome and diabetes as well as hypertension. However, it remains undetermined how renin-angiotensin system is implicated in feeding behavior. Here, we show that angiotensin II type 1 (AT1) receptor signaling regulates the hypothalamic neurocircuit that is involved in the control of food intake. Compared with wild-type Agtr1a+/+ mice, AT1 receptor knock-out (Agtr1a−/−) mice were hyperphagic and obese with ...

  5. Deficiency of Angiotensin Type 1a Receptors in Adipocytes Reduces Differentiation and Promotes Hypertrophy of Adipocytes in Lean Mice

    OpenAIRE

    Putnam, Kelly; Batifoulier-Yiannikouris, Frederique; Bharadwaj, Kalyani G.; Lewis, Eboni; Karounos, Michael; Daugherty, Alan; Cassis, Lisa A.

    2012-01-01

    Adipocytes express angiotensin receptors, but the direct effects of angiotensin II (AngII) stimulating this cell type are undefined. Adipocytes express angiotensin type 1a receptor (AT1aR) and AT2R, both of which have been implicated in obesity. In this study, we determined the effects of adipocyte AT1aR deficiency on adipocyte differentiation and the development of obesity in mice fed low-fat (LF) or high-fat (HF) diets. Mice expressing Cre recombinase under the control of the aP2 promoter w...

  6. Angiotensin-Receptor Blocker, Angiotensin-Converting Enzyme Inhibitor, and Risks of Atrial Fibrillation: A Nationwide Cohort Study.

    Science.gov (United States)

    Hsieh, Yu-Cheng; Hung, Chen-Ying; Li, Cheng-Hung; Liao, Ying-Chieh; Huang, Jin-Long; Lin, Ching-Heng; Wu, Tsu-Juey

    2016-05-01

    Both angiotensin-receptor blockers (ARB) and angiotensin-converting enzyme inhibitors (ACEI) have protective effects against atrial fibrillation (AF). The differences between ARB and ACEI in their effects on the primary prevention of AF remain unclear. This study compared ARB and ACEI in combined antihypertensive medications for reducing the risk of AF in patients with hypertension, and determined which was better for AF prevention in a nationwide cohort study.Patients aged ≥55 years and with a history of hypertension were identified from Taiwan National Health Insurance Research Database. Medical records of 25,075 patients were obtained, and included 6205 who used ARB, 8034 who used ACEI, and 10,836 nonusers (no ARB or ACEI) in their antihypertensive regimen. Cox regression models were applied to estimate the hazard ratio (HR) for new-onset AF.During an average of 7.7 years' follow-up, 1619 patients developed new-onset AF. Both ARB (adjusted HR: 0.51, 95% CI 0.44-0.58, P reduced the risk of AF compared to nonusers. Subgroup analysis showed that ARB and ACEI were equally effective in preventing new-onset AF regardless of age, gender, the presence of heart failure, diabetes, and vascular disease, except for those with prior stroke or transient ischemic attack (TIA). ARB prevents new-onset AF better than ACEI in patients with a history of stroke or TIA (log-rank P = 0.012).Both ARB and ACEI reduce new-onset AF in patients with hypertension. ARB prevents AF better than ACEI in patients with a history of prior stroke or TIA. PMID:27196491

  7. Prospects for angiotensin receptor blockers in diabetic retinopathy

    DEFF Research Database (Denmark)

    Sjølie, Anne Katrin

    2007-01-01

    Retinopathy is the most common microvascular complication of diabetes mellitus, and is an important cause of blindness worldwide. Clinical trials have demonstrated that tight metabolic control inhibits the progression of retinopathy. Good blood pressure control has been shown to be protective in...... type 2 diabetes, and it may also reduce proliferative retinopathy in type 1 diabetes. However, such control is often difficult to achieve in clinical practice, and may be associated with problems such as hypoglycaemia. New therapies are therefore needed to reduce the risk of retinopathy. There is...... growing evidence that the renin-angiotensin system (RAS) plays an important role in the pathogenesis of diabetic retinopathy, and this has led to interest in RAS inhibitors as agents to prevent retinopathy. Several trials have suggested that ACE inhibitor therapy can inhibit progression of retinopathy...

  8. Effect of angiotensin II receptor blockade on proximal tubular fluid reabsorption

    DEFF Research Database (Denmark)

    Leyssac, P P; Karlsen, F M; Holstein-Rathlou, N H

    1997-01-01

    The effect of physiological concentrations of angiotensin II on proximal tubular fluid reabsorption remains controversial. To investigate the effect of blockade of intratubular AT1 receptors on tubular reabsorption, losartan (10(-5) M) was administered by microperfusion into an early proximal...... flow rate decreased by 2.0 +/- 0.8 nl/min, and early distal NaCl concentration decreased by 4.3 +/- 0.8 mM (mean +/- SE). No changes were observed after microperfusion with saline. Because the tubuloglomerular feedback mechanism was operating in the closed-loop mode, the decreased NaCl load to the...... early and late proximal convolutions was estimated to be 7.8 nl/min (approximately 36%). It is concluded that a decrease in local luminal angiotensin II levels and/or AT1 receptor activity under free flow conditions increases the rate of proximal tubular fluid reabsorption....

  9. Dual angiotensin receptor and neprilysin inhibition as an alternative to angiotensin-converting enzyme inhibition in patients with chronic systolic heart failure

    DEFF Research Database (Denmark)

    McMurray, John J V; Packer, Milton; Desai, Akshay S;

    2013-01-01

    AIMS: Although the focus of therapeutic intervention has been on neurohormonal pathways thought to be harmful in heart failure (HF), such as the renin-angiotensin-aldosterone system (RAAS), potentially beneficial counter-regulatory systems are also active in HF. These promote vasodilatation and...... natriuresis, inhibit abnormal growth, suppress the RAAS and sympathetic nervous system, and augment parasympathetic activity. The best understood of these mediators are the natriuretic peptides which are metabolized by the enzyme neprilysin. LCZ696 belongs to a new class of drugs, the angiotensin receptor...

  10. Autoantibody-mediated angiotensin receptor activation contributes to preeclampsia through TNF-alpha signaling

    OpenAIRE

    Irani, Roxanna A.; Zhang, Yujin; Zhou, Cissy Chenyi; Blackwell, Sean C.; Hicks, M. John; Ramin, Susan M.; Kellems, Rodney E.; Xia, Yang

    2010-01-01

    Preeclampsia is a prevalent life-threatening hypertensive disorder of pregnancy whose pathophysiology remains largely undefined. Recently, a circulating maternal autoantibody, the angiotensin II type I receptor agonistic autoantibody (AT1-AA), has emerged as a contributor to disease features. Increased circulating maternal tumor necrosis factor alpha (TNF-α) is also associated with the disease, however it is unknown if this factor directly contributes to preeclamptic symptoms. Here we report ...

  11. Renal dopamine and angiotensin II receptor signaling in age-related hypertension

    OpenAIRE

    Chugh, Gaurav; Pokkunuri, Indira; Asghar, Mohammad

    2012-01-01

    Kidneys play a vital role in long-term regulation of blood pressure. This is achieved by actions of many renal and nonrenal factors acting on the kidney that help maintain the body's water and electrolyte balance and thus control blood pressure. Several endogenously formed or circulating hormones/peptides, by acting within the kidney, regulate fluid and water homeostasis and blood pressure. Dopamine and angiotensin II are the two key renal factors that, via acting on their receptors and count...

  12. Use of ACE Inhibitors and Angiotensin Receptor Blockers and Primary Breast Cancer Outcomes

    OpenAIRE

    Chae, Young Kwang; Brown, Erika N.; Lei, Xiudong; Melhem-Bertrandt, Amal; Giordano, Sharon H.; Litton, Jennifer K.; Hortobagyi, Gabriel N; Gonzalez-Angulo, Ana M.; Chavez-MacGregor, Mariana

    2013-01-01

    BACKGROUND: ACE inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) may have anti-tumor properties. We investigated whether the use of ACEI/ARBs affects the clinical outcomes of primary breast cancer patients receiving taxane and anthracycline-based neoadjuvant chemotherapy. METHODS: We included 1449 patients with diagnosis of invasive primary breast cancer diagnosed at the MD Anderson Cancer Center between 1995 and 2007 who underwent neoadjuvant chemotherapy. Of them, 160 (11%) patie...

  13. Expression and clinical significance of angiotensin II type 1 receptor in human hepatocellular carcinoma

    OpenAIRE

    Duan, Yun-fei; Li, Xiao-dong; Zhu, Feng; Zhang, Feng

    2013-01-01

    This study aimed to investigate the expression of angiotensin II type 1 receptor (AT-1R) mRNA and the AT-1R protein in human primary hepatocellular carcinoma (PHC), and to attempt to elucidate their association with pathological and clinical characteristics. Fresh tumor and normal liver tissues were obtained from 44 patients with PHC following hepatectomies. AT-1R mRNA levels were quantitatively analyzed by quantitative polymerase chain reaction (qPCR) while the protein levels were assessed b...

  14. Angiotensin II Receptor Blocker Ameliorates Stress-Induced Adipose Tissue Inflammation and Insulin Resistance

    OpenAIRE

    Motoharu Hayashi; Kyosuke Takeshita; Yasuhiro Uchida; Koji Yamamoto; Ryosuke Kikuchi; Takayuki Nakayama; Emiko Nomura; Xian Wu Cheng; Tadashi Matsushita; Shigeo Nakamura; Toyoaki Murohara

    2014-01-01

    A strong causal link exists between psychological stress and insulin resistance as well with hypertension. Meanwhile, stress-related responses play critical roles in glucose metabolism in hypertensive patients. As clinical trials suggest that angiotensin-receptor blocker delays the onset of diabetes in hypertensive patients, we investigated the effects of irbesartan on stress-induced adipose tissue inflammation and insulin resistance. C57BL/6J mice were subjected to 2-week intermittent restra...

  15. Vascular oxidative stress upregulates angiotensin II type I receptors via mechanisms involving nuclear factor kappa B

    OpenAIRE

    Bhatt, Siddhartha R.; Lokhandwala, Mustafa F.; Banday, Anees Ahmad

    2014-01-01

    The association of oxidative stress with hypertension is well known. However, a causal role of oxidative stress in hypertension is unclear. Vascular angiotensin II type 1 receptor (AT1R) upregulation is a prominent contributor to pathogenesis of hypertension. However, the mechanisms causing this upregulation are unknown. Oxidative stress is an important regulator of protein expression via activation of transcription factors such as nuclear factor kappa B (NFκB). The present study was carried ...

  16. Differential involvement of hippocampal angiotensin 1 receptors in learning and memory processes in bulbectomized rats

    OpenAIRE

    Tashev E. Roman; Margarita S. Ivanova; Stiliana P. Belcheva; Iren P. Belcheva

    2016-01-01

    There is conflicting evidence regarding the effect of AT1 receptor antagonists on learning and memory processes. The effects of angiotensin II and losartan administration into CA1 hippocampal area on the avoidance performance in olfactory bulbectomized (OBX) rats using active avoidance (shuttle box) test and passive avoidance (step through) test were investigated. Rats were microinjected unilaterally through implanted guide cannulas into the CA1 area of the dorsal hippocampus and the drugs we...

  17. Ischemic heart disease down-regulates angiotensin type 1 receptor mRNA in human coronary arteries

    DEFF Research Database (Denmark)

    Wackenfors, Angelica; Emilson, Malin; Ingemansson, Richard;

    2004-01-01

    , the suitability of artery culture for studying angiotensin receptor changes was evaluated by in vitro pharmacology and real-time PCR. The angiotensin type 1 (AT1) receptor mRNA levels were down-regulated in human coronary arteries from patients with ischemic heart disease as compared to controls (P<0.......05). Culture of coronary arteries for 48 h induced down-regulation of the angiotensin AT1 and AT2 receptor mRNA levels and also a less efficacious angiotensin II-induced vasoconstriction (Emax=103+/-2% before and 23+/-7% after artery culture, P<0.001). Artery culture may thus be a suitable method for studying...

  18. Angiotensin II type 2 receptor- and acetylcholine-mediated relaxation: essential contribution of female sex hormones and chromosomes.

    Science.gov (United States)

    Pessôa, Bruno Sevá; Slump, Denise E; Ibrahimi, Khatera; Grefhorst, Aldo; van Veghel, Richard; Garrelds, Ingrid M; Roks, Anton J M; Kushner, Steven A; Danser, A H Jan; van Esch, Joep H M

    2015-08-01

    Angiotensin-induced vasodilation, involving type 2 receptor (AT2R)-induced generation of nitric oxide (NO; by endothelial NO synthase) and endothelium-derived hyperpolarizing factors, may be limited to women. To distinguish the contribution of female sex hormones and chromosomes to AT2R function and endothelium-derived hyperpolarizing factor-mediated vasodilation, we made use of the four-core genotype model, where the testis-determining Sry gene has been deleted (Y(-)) from the Y chromosome, allowing XY(-) mice to develop a female gonadal phenotype. Simultaneously, by incorporating the Sry gene onto an autosome, XY(-)Sry and XXSry transgenic mice develop into gonadal male mice. Four-core genotype mice underwent a sham or gonadectomy (GDX) operation, and after 8 weeks, iliac arteries were collected to assess vascular function. XY(-)Sry male mice responded more strongly to angiotensin than XX female mice, and the AT2R antagonist PD123319 revealed that this was because of a dilator AT2R-mediated effect occurring exclusively in XX female mice. The latter could not be demonstrated in XXSry male and XY(-) female mice nor in XX female mice after GDX, suggesting that it depends on both sex hormones and chromosomes. Indeed, treating C57bl/6 GDX male mice with estrogen could not restore angiotensin-mediated, AT2R-dependent relaxation. To block acetylcholine-induced relaxation of iliac arteries obtained from four-core genotype XX mice, both endothelial NO synthase and endothelium-derived hyperpolarizing factor inhibition were required, whereas in four-core genotype XY animals, endothelial NO synthase inhibition alone was sufficient. These findings were independent of gonadal sex and unaltered after GDX. In conclusion, AT2R-induced relaxation requires both estrogen and the XX chromosome sex complement, whereas only the latter is required for endothelium-derived hyperpolarizing factors. PMID:26056343

  19. Direct stimulation of angiotensin II type 2 receptor enhances spatial memory

    DEFF Research Database (Denmark)

    Jing, Fei; Mogi, Masaki; Sakata, Akiko;

    2012-01-01

    evaluated by the Morris water maze test in C57BL6 mice, but this effect was not observed in AT(2) receptor-deficient mice. However, C21-induced cognitive enhancement in C57BL6 mice was attenuated by coadministration of icatibant, a bradykinin B(2) receptor antagonist. Administration of C21 dose dependently......We examined the possibility that direct stimulation of the angiotensin II type 2 (AT(2)) receptor by a newly generated direct AT(2) receptor agonist, Compound 21 (C21), enhances cognitive function. Treatment with C21 intraperitoneal injection for 2 weeks significantly enhanced cognitive function...... cognitive decline in this model. These results suggest that a direct AT(2) receptor agonist, C21, enhances cognitive function at least owing to an increase in CBF, enhancement of f-EPSP, and neurite outgrowth in hippocampal neurons....

  20. Effect of angiotensinreceptor 1 antisense oligodoexynucleotides on physiological and pathophysiological growth of cardiomyocytes

    Institute of Scientific and Technical Information of China (English)

    Ying WANG; Jin-ming WANG; Shu-xun Yan; Ming-jiang LI; Jian-jun LI

    2004-01-01

    AIM: To evaluate the role of angiotensinreceptor 1 antisense oligodexynucleotides (AT1R-AS-ODNs) on physiological and pathophysiological growth of cardiomyocytes from normotensive rats. METHODS: Cardiomyocytes were transfected with AT1R-AS-ODNs (200 nmol/L) followed by treatment with or without angiotensin Ⅱ (1 μmol/L).In situ hybridization and Western blot were used for AT1R mRNA and protein detection, respectively. c-Jun Nterminal protein kinase (JNK) activity was characterized by immune complex kinase assay. c-Jun protein expression was examined by immunocytochemistry. DNA content was detected by flow cytometric assay. Atrial natriuretic factor (ANF) expression was identified by radioimmunoassay. RESULTS: Treatment with AT1R-AS-ODNs for 24 h resulted in 51.2 % decrease in AT1R mRNA and 60.7 % in protein (P<0.05 vs control). However, the basal level of JNK activity, c-Jun protein expression, and DNA content were not altered by AT1R-AS treatment in absence of overactive hormonal system. After treatment with angiotensin Ⅱ for 30 min, both p46JNK and p54JNK were robustly activated. By 2 h, c-Jun protein expression was increased. By 24 h, angiotensin Ⅱ caused a marked increase both in G0/G1 and G2/M DNA content, and increased ANF expression by 1.8-fold. All these were inhibited by AT1R-AS-ODNs pretreatment. In contrast, sense sequence was ineffective. CONCLUSION: Decrease of AT1R expression by AS-ODNs did not interfere with normal growth, but protected cardiomyocytes from angiotensin Ⅱ-dependent pathophysiological growth.

  1. Combined Angiotensin Receptor Modulation in the Management of Cardio-Metabolic Disorders

    DEFF Research Database (Denmark)

    Paulis, Ludovit; Foulquier, Sébastien; Namsolleck, Pawel;

    2016-01-01

    Cardiovascular and metabolic disorders, such as hypertension, insulin resistance, dyslipidemia or obesity are linked with chronic low-grade inflammation and dysregulation of the renin-angiotensin system (RAS). Consequently, RAS inhibition by ACE inhibitors or angiotensin AT1 receptor (AT1R......) blockers is the evidence-based standard for cardiovascular risk reduction in high-risk patients, including diabetics with albuminuria. In addition, RAS inhibition reduces the new onset of diabetes mellitus. Yet, the high and increasing prevalence of metabolic disorders, and the high residual risk even....... Therefore, a concept of dual AT1R/AT2R modulation emerges as a putative means for risk reduction in cardio-metabolic diseases. The approach employing simultaneous RAS blockade (AT1R) and RAS stimulation (AT2R) is distinct from previous attempts of double intervention in the RAS by dual blockade. Dual...

  2. The Prorenin and (Prorenin Receptor: New Players in the Brain Renin-Angiotensin System?

    Directory of Open Access Journals (Sweden)

    Wencheng Li

    2012-01-01

    Full Text Available It is well known that the brain renin-angiotensin (RAS system plays an essential role in the development of hypertension, mainly through the modulation of autonomic activities and vasopressin release. However, how the brain synthesizes angiotensin (Ang II has been a debate for decades, largely due to the low renin activity. This paper first describes the expression of the vasoconstrictive arm of RAS components in the brain as well as their physiological and pathophysiological significance. It then focus on the (prorenin receptor (PRR, a newly discovered component of the RAS which has a high level in the brain. We review the role of prorenin and PRR in peripheral organs and emphasize the involvement of brain PRR in the pathogenesis of hypertension. Some future perspectives in PRR research are heighted with respect to novel therapeutic target for the treatment of hypertension and other cardiovascular diseases.

  3. A combined role of calcium channel blockers and angiotensin receptor blockers in stroke prevention

    Directory of Open Access Journals (Sweden)

    Ji-Guang Wang

    2009-07-01

    Full Text Available Ji-Guang WangCentre for Epidemiological Studies and Clinical Trials, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, ChinaAbstract: Stroke is a leading cause of death and disability worldwide. The importance of lowering blood pressure for reducing the risk of stroke is well established. However, not all the benefits of antihypertensive treatments in stroke can be accounted for by reductions in BP and there may be differences between antihypertensive classes as to which provides optimal protection. Dihydropyridine calcium channel blockers, such as amlodipine, and angiotensin receptor blockers, such as valsartan, represent the two antihypertensive drug classes with the strongest supportive data for the prevention of stroke. Therefore, when combination therapy is required, a combination of these two antihypertensive classes represents a logical approach.Keywords: stroke, angiotensin, calcium channel, cerebrovascular, hypertension, blood pressure

  4. Chronic ACE inhibitor treatment increases angiotensin type 1 receptor binding in vivo in the dog kidney

    International Nuclear Information System (INIS)

    PET imaging has been recently introduced for investigating the type 1 angiotensin II receptor (AT1R) in vivo. The goal of the present study was to investigate the effects of acute and chronic exposure to angiotensin converting enzyme inhibitors (ACEI) on the AT1R in the dog kidney. Animals were imaged at baseline, after acute intravenous ACEI treatment and after a chronic 2-week exposure to an oral ACEI. Control animals were imaged at identical time points in the absence of ACEI treatment. In vivo AT1R binding expressed by Ki was increased in the renal cortex by chronic ACEI treatment (p 1R density (Bmax) also revealed significant increases in AT1R in isolated glomeruli (p 1R binding in vivo in the dog renal cortex. (orig.)

  5. Comparative Effects of Angiotensin Receptor BlockadeandACE Inhibition on the Fibrinolytic and Inflammatory Responses to Cardiopulmonary Bypass

    OpenAIRE

    Billings, Frederic T.; Balaguer, Jorge M.; Yu, Chang; Wright, Patricia; Petracek, Michael R.; Byrne, John G; Brown, Nancy J.; Pretorius, Mias

    2012-01-01

    The effects of angiotensin-converting enzyme (ACE) inhibition and angiotensin II type 1 receptor blockade (ARB) on fibrinolysis and inflammation following cardiopulmonary bypass (CPB) are uncertain. This study tested the hypothesis that ACE inhibition enhances fibrinolysis and inflammation to greater extent than ARB in patients undergoing CPB.One week to five days prior to surgery, patients were randomized to ramipril 5mg/day,candesartan 16mg/day or placebo.ACE inhibition increased intraopera...

  6. Angiotensin Receptor Blockade Increases Pancreatic Insulin Secretion and Decreases Glucose Intolerance during Glucose Supplementation in a Model of Metabolic Syndrome

    OpenAIRE

    Rodriguez, Ruben; Viscarra, Jose A.; Minas, Jacqueline N.; Nakano, Daisuke; Nishiyama, Akira; Ortiz, Rudy M.

    2012-01-01

    Renin-angiotensin system blockade improves glucose intolerance and insulin resistance, which contribute to the development of metabolic syndrome. However, the contribution of impaired insulin secretion to the pathogenesis of metabolic syndrome is not well defined. To assess the contributions of angiotensin receptor type 1 (AT1) activation and high glucose intake on pancreatic function and their effects on insulin signaling in skeletal muscle and adipose tissue, an oral glucose tolerance test ...

  7. Pharmacologic perspectives of functional selectivity by the angiotensin II type 1 receptor

    DEFF Research Database (Denmark)

    Aplin, Mark; Christensen, Gitte Lund; Hansen, Jakob Lerche

    2008-01-01

    The angiotensin II type 1 (AT(1)) receptor plays a key role in cardiovascular pathophysiology, and it is a major pharmacologic target in the treatment of many cardiovascular disorders. However, AT(1) receptor activation is also involved in adaptive responses to altered hemodynamic demands and to...... sudden injury occurring in the circulatory system. Hence, current drugs that block all AT(1) receptor actions most likely leave room for improvement. Recent developments show that two major signaling pathways used by the AT(1) receptor may be dissected by pharmacologic means. Key pathologic responses...... blockade of G protein actions and simultaneous activation of G protein-dependent or -independent signaling could therefore be desirable in certain situations. The previously unappreciated concept of "functional selectivity" makes this exact strategy feasible and may yield improved drugs for cardiovascular...

  8. AT(1) receptor Gαq protein-independent signalling transcriptionally activates only a few genes directly, but robustly potentiates gene regulation from the β2-adrenergic receptor

    DEFF Research Database (Denmark)

    Christensen, Gitte Lund; Knudsen, Steen; Schneider, Mikael; Aplin, Mark; Gammeltoft, Steen; Sheikh, Søren P; Hansen, Jakob L

    2011-01-01

    potentiated β2-adrenergic receptor-stimulated gene expression. These novel findings indicate that the Gαq protein-independent signalling mainly modifies the transcriptional response governed by other signalling pathways, while direct induction of gene expression by the AT(1)R is dependent on classical Gαq......-independent signalling from the AT(1)R interact with transcriptional regulators and promote phosphorylation of nuclear proteins. However, the relative contribution of Gαq protein-independent signalling in AT(1)R mediated transcriptional regulation remains elusive. We here present a comprehensive comparative analysis of...... Gαq protein-dependent and -independent regulation of AT(1)R mediated gene expression. We found angiotensin II to regulate 212 genes, whereas Gαq-independent signalling obtained with the biased agonist, SII angiotensin II only regulated few genes. Interestingly, SII angiotensin II, like Ang II vastly...

  9. Direct angiotensin II type 2 receptor stimulation decreases dopamine synthesis in the rat striatum.

    Science.gov (United States)

    Mertens, Birgit; Vanderheyden, Patrick; Michotte, Yvette; Sarre, Sophie

    2010-06-01

    A relationship between the central renin angiotensin system and the dopaminergic system has been described in the striatum. However, the role of the angiotensin II type 2 (AT(2)) receptor in this interaction has not yet been established. The present study examined the outcome of direct AT(2) receptor stimulation on dopamine (DA) release and synthesis by means of the recently developed nonpeptide AT(2) receptor agonist, compound 21 (C21). The effects of AT(2) receptor agonism on the release of DA and its major metabolite 3,4-dihydroxyphenylacetic acid (DOPAC) and on the activity of tyrosine hydroxylase (TH), the rate-limiting enzyme in the catecholamine biosynthesis, were investigated using in vivo microdialysis. Local administration of C21 (0.1 and 1 microM) resulted in a decrease of the extracellular DOPAC levels, whereas extracellular DA concentrations remained unaltered, suggesting a reduced synthesis of DA. This effect was mediated by the AT(2) receptor since it could be blocked by the AT(2) receptor antagonist PD123319 (1 microM). A similar effect was observed after local striatal (10 nM) as well as systemic (0.3 and 3 mg/kg i.p.) administration of the AT(1) receptor antagonist, candesartan. TH activity as assessed by accumulation of extracellular levels of L-DOPA after inhibition of amino acid decarboxylase with NSD1015, was also reduced after local administration of C21 (0.1 and 1 microM) and candesartan (10 nM). Together, these data suggest that AT(1) and AT(2) receptors in the striatum exert an opposite effect on the modulation of DA synthesis rather than DA release. PMID:20097214

  10. Troglitazone stimulates β-arrestin-dependent cardiomyocyte contractility via the angiotensin II type 1A receptor

    International Nuclear Information System (INIS)

    Peroxisome proliferator-activated receptor γ (PPARγ) agonists are commonly used to treat cardiovascular diseases, and are reported to have several effects on cardiovascular function that may be due to PPARγ-independent signaling events. Select angiotensin receptor blockers (ARBs) interact with and modulate PPARγ activity, thus we hypothesized that a PPARγ agonist may exert physiologic effects via the angiotensin II type 1A receptor (AT1AR). In AT1AR-overexpressing HEK 293 cells, both angiotensin II (Ang II) and the PPARγ agonist troglitazone (Trog) enhanced AT1AR internalization and recruitment of endogenous β-arrestin1/2 (βarr1/2) to the AT1AR. A fluorescence assay to measure diacylglycerol (DAG) accumulation showed that although Ang II induced AT1AR-Gq protein-mediated DAG accumulation, Trog had no impact on DAG generation. Trog-mediated recruitment of βarr1/2 was selective to AT1AR as the response was prevented by an ARB- and Trog-mediated βarr1/2 recruitment to β1-adrenergic receptor (β1AR) 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 βarr2-dependent, as cardiomyocytes isolated from βarr2-KO mice showed blunted contractile responses to Trog. These findings show for the first time that the PPARγ agonist Trog acts at the AT1AR to simultaneously block Gq protein activation and induce the recruitment of βarr1/2, which leads to an increase in cardiomyocyte contractility.

  11. Reduced expression of angiotensin II and angiotensin receptor type 1 and type 2 in resistance arteries from nasal lesions in granulomatosis with polyangiitis (Wegener's granulomatosis)

    DEFF Research Database (Denmark)

    Dimitrijevic, I; Rissler, P; Luts, L;

    2011-01-01

    OBJECTIVES: Angiotensin II (ANGII) is involved in vessel inflammation and is important in the development of cardiovascular disorders such as atherosclerosis. During active disease, patients with granulomatosis with polyangiitis (GPA; Wegener's granulomatosis) have accelerated atherosclerosis...... and ANGII inhibitors are recommended to these patients to reduce atherosclerosis. We assessed the hypothesis that the expression of ANGII and its receptors in arteries in granulomatous lesions change in GPA. METHODS: ANGII and angiotensin receptors were quantified in vessels from granulomatous lesions from...... patients with GPA using immunohistochemistry. Anti- ANGI type 1 (AT1) and type 2 (AT2) antibodies were applied on formalin-fixed and paraffin-embedded biopsies from nasal mucous membranes from eight patients with GPA and eight controls. RESULTS: ANGII expression was localized to the endothelial cells (ECs...

  12. Direct Angiotensin II Type 2 Receptor Stimulation Ameliorates Insulin Resistance in Type 2 Diabetes Mice with PPARγ Activation

    DEFF Research Database (Denmark)

    Ohshima, Kousei; Mogi, Masaki; Jing, Fei;

    2012-01-01

    The role of angiotensin II type 2 (AT(2)) receptor stimulation in the pathogenesis of insulin resistance is still unclear. Therefore we examined the possibility that direct AT(2) receptor stimulation by compound 21 (C21) might contribute to possible insulin-sensitizing/anti-diabetic effects in type...... 2 diabetes (T2DM) with PPARγ activation, mainly focusing on adipose tissue....

  13. Increased expression of vascular endothelin type B and angiotensin type 1 receptors in patients with ischemic heart disease

    Directory of Open Access Journals (Sweden)

    Malmsjö Malin

    2009-08-01

    Full Text Available Abstract Background Endothelin-1 and angiotensin II are strong vasoconstrictors. Patients with ischemic heart disease have elevated plasma levels of endothelin-1 and angiotensin II and show increased vascular tone. The aim of the present study was to examine the endothelin and angiotensin II receptor expression in subcutaneous arteries from patients with different degrees of ischemic heart disease. Methods Subcutaneous arteries were obtained, by biopsy from the abdomen, from patients undergoing coronary artery bypass graft (CABG surgery because of ischemic heart disease (n = 15, patients with angina pectoris without established myocardial infarction (n = 15 and matched cardiovascular healthy controls (n = 15. Endothelin type A (ETA and type B (ETB, and angiotensin type 1 (AT1 and type 2 (AT2 receptors expression and function were examined using immunohistochemistry, Western blot and in vitro pharmacology. Results ETA and, to a lesser extent, ETB receptor staining was observed in the healthy vascular smooth muscle cells. The level of ETB receptor expression was higher in patients undergoing CABG surgery (250% ± 23%; P B receptor agonist sarafotoxin S6c, compared to healthy controls (P A receptors. AT1 and, to a lesser extent, AT2 receptor immunostaining was seen in the vascular smooth muscle cells. The level of AT1 receptor expression was higher in both the angina pectoris (128% ± 25%; P 1 receptor expression was confirmed by Western blotting. Myograph experiment did however not show any change in vasoconstriction to angiotensin II in CABG patients compared to healthy controls (P = n.s. Conclusion The results demonstrate, for the first time, upregulation of ETB and AT1 receptors in vascular smooth muscle cells in ischemic heart disease. These receptors may play a role in the pathophysiology of ischemic heart disease and could provide important targets for pharmaceutical interventions.

  14. Cognitive enhancing effect of angiotensin-converting enzyme inhibitors and angiotensin receptor blockers on learning and memory

    Directory of Open Access Journals (Sweden)

    V S Nade

    2015-01-01

    Conclusion: The results suggest that the cognitive enhancing effect of ACEI and ARBs may be due to inhibition of AChE or by regulation of antioxidant system or increase in formation of angiotensin IV.

  15. Incidence and influencing factors of aldosterone breakthrough during therapy with angiotensinreceptor bockers alone,or combined with angiotensin-converting enzyme inhibitors in patients with non-diabetic nephropathy

    Institute of Scientific and Technical Information of China (English)

    梁敏

    2013-01-01

    Objective To investigate the incidence and influen-cing factors of aldosterone breakthrough during therapy with angiotensinreceptor blockers(ARB) alone,or combined with angiotensin-converting enzyme inhibitors(ACEI) in Chinese patients with non-diabetic

  16. A different role of angiotensin II type 1a receptor in the development and hypertrophy of plantaris muscle in mice.

    Science.gov (United States)

    Zempo, Hirofumi; Suzuki, Jun-Ichi; Ogawa, Masahito; Watanabe, Ryo; Isobe, Mitsuaki

    2016-02-01

    The role of angiotensin II type 1 (AT1) receptors in muscle development and hypertrophy remains unclear. This study was designed to reveal the effects that a loss of AT1 receptors has on skeletal muscle development and hypertrophy in mice. Eight-week-old male AT1a receptor knockout (AT1a(-/-)) mice were used for this experiment. The plantaris muscle to body weight ratio, muscle fiber cross-sectional area, and number of muscle fibers of AT1a(-/-) mice was significantly greater than wild type (WT) mice in the non-intervention condition. Next, the functional overload (OL) model was used to induce plantaris muscle hypertrophy by surgically removing the two triceps muscles consisting of the calf, soleus, and gastrocnemius muscles in mice. After 14 days of OL intervention, the plantaris muscle weight, the amount of fiber, and the fiber area increased. However, the magnitude of the increment of plantaris weight was not different between the two strains. Agtr1a mRNA expression did not change after OL in WT muscle. Actually, the Agt mRNA expression level of WT-OL was lower than WT-Control (C) muscle. An atrophy-related gene, atrogin-1 mRNA expression levels of AT1a(-/-)-C, WT-OL, and AT1a(-/-)-OL muscle were lower than that of WT-C muscle. Our findings suggest that AT1 receptor contributes to plantaris muscle development via atrogin-1 in mice. PMID:26025227

  17. Impact of drug price adjustments on utilization of and expenditures on angiotensin-converting enzyme inhibitors and angiotensin receptor blockers in Taiwan

    Directory of Open Access Journals (Sweden)

    Huang Shiou-Huei

    2012-05-01

    Full Text Available Abstract Background A previous study has suggested that drug price adjustments allow physicians in Taiwan to gain greater profit by prescribing generic drugs. To better understand the effect of price adjustments on physician choice, this study used renin-angiotensin drugs (including angiotensin-converting enzyme inhibitors [ACEIs] and angiotensin receptor blockers [ARBs] to examine the impact of price adjustments on utilization of and expenditures on patented and off-patent drugs with the same therapeutic indication. Methods Using the Taiwan’s Longitudinal Health Insurance Database (2005, we identified 147,157 patients received ACEIs and/or ARBs between 1997 and 2008. The annual incident and prevalent users of ACEIs, ARBs and overall renin-angiotensin drugs were examined. Box-Tiao intervention analysis was applied to assess the impact of price adjustments on monthly utilization of and expenditures on these drugs. ACEIs were divided into patented and off-patent drugs, off-patent ACEIs were further divided into original brands and generics, and subgroup analyses were performed. Results The number of incident renin-angiotensin drug users decreased over the study period. The number of prevalent ARB users increased and exceeded the cumulative number of first-time renin-angiotensin drug users starting on ARBs, implying that some patients switched from ACEIs to ARBs. After price adjustments, long term trend increases in utilization were observed for patented ACEIs and ARBs; a long-term trend decrease was observed for off-patent ACEIs; long-term trend change was not significant for overall renin-angiotensin drugs. Significant long-term trend increases in expenditures were observed for patented ACEIs after price adjustment in 2007 (200.9%, p = 0.0088 and in ARBs after price adjustments in 2001 (173.4%, p  Conclusions Price adjustments did not achieve long-term cost savings for overall renin-angiotensin drugs. Possible switching from ACEIs to ARBs

  18. Chronic ACE inhibitor treatment increases angiotensin type 1 receptor binding in vivo in the dog kidney

    Energy Technology Data Exchange (ETDEWEB)

    Zober, Tamas G. [Johns Hopkins University, Departments of Radiology and Surgery, Baltimore, MD (United States); Semmelweis University, Department of Pathophysiology, Budapest (Hungary); Fabucci, Maria E.; Zheng, Wei; Sandberg, Kathryn [Georgetown University, Department of Medicine, Washington, DC (United States); Brown, Phillip R.; Seckin, Esen; Mathews, William B. [Johns Hopkins University, Departments of Radiology and Surgery, Baltimore, MD (United States); Szabo, Zsolt [Johns Hopkins University, Departments of Radiology and Surgery, Baltimore, MD (United States); Johns Hopkins Outpatient Center, Division of Nuclear Medicine, Baltimore, MD (United States)

    2008-06-15

    PET imaging has been recently introduced for investigating the type 1 angiotensin II receptor (AT{sub 1}R) in vivo. The goal of the present study was to investigate the effects of acute and chronic exposure to angiotensin converting enzyme inhibitors (ACEI) on the AT{sub 1}R in the dog kidney. Animals were imaged at baseline, after acute intravenous ACEI treatment and after a chronic 2-week exposure to an oral ACEI. Control animals were imaged at identical time points in the absence of ACEI treatment. In vivo AT{sub 1}R binding expressed by K{sub i} was increased in the renal cortex by chronic ACEI treatment (p < 0.05). In vitro measurements of AT{sub 1}R density (B{sub max}) also revealed significant increases in AT{sub 1}R in isolated glomeruli (p < 0.05). Plasma renin activity was increased, but angiotensin II (Ang II) and the Ang II/Ang I ratio showed a weak correlation with chronic ACEI treatment, consistent with an Ang II escape phenomenon. This study reveals, for the first time, that chronic ACEI treatment increases AT{sub 1}R binding in vivo in the dog renal cortex. (orig.)

  19. Association between Angiotensin II Type 1 Receptor Polymorphism and Sudden Cardiac Death in Myocardial Infarction

    Science.gov (United States)

    Kruzliak, Peter; Kovacova, Gabriela; Pechanova, Olga; Balogh, Stefan

    2013-01-01

    Objective. The renin-angiotensin system is involved in the pathogenesis of coronary artery disease and myocardial infarction (MI). Angiotensin II (Ang II) has many adverse effects such as vasoconstriction and vascular remodeling, and these actions are mediated by the angiotensin II type 1 receptor (AT1R). Patients and Methods. A total of 1376 patients were recruited from January 2010 to April 2012. The study group consisted of 749 patients with ACS (317 females and 432 males) and of 627 healthy controls. Results. The ACS patients demonstrated a lower proportion of AA genotypes and AC genotypes but higher proportions of CC genotypes than the control population. The AT1R CC genotype conferred a 2.76-fold higher risk of MI compared with the genotype AC and AA. In addition, the CC genotype was also associated with a 4.08 times higher risk of left anterior descending artery infarction and a 3.07 times higher risk of anterior wall infarction. We also found that the CC genotype was independently associated with sudden cardiac death. In Summary. This study demonstrated that the AT1R CC genotype is an independent risk factor for ACS incidence, and this genotype is associated with a greater ACS severity and greater risk of sudden cardiac death. PMID:24167376

  20. Distinct angiotensin II receptor in primary cultures of glial cells from rat brain

    Energy Technology Data Exchange (ETDEWEB)

    Raizada, M.K.; Phillips, M.I.; Crews, F.T.; Sumners, C.

    1987-07-01

    Angiotensin II (Ang-II) has profound effects on the brain. Receptors for Ang-II have been demonstrated on neurons, but no relationship between glial cells and Agn-II has been established. Glial cells (from the hypothalamus and brain stem of 1-day-old rat brains) in primary culture have been used to demonstrate the presence of specific Ang-II receptors. Binding of /sup 125/I-Ang-II to glial cultures was rapid, reversible, saturable, and specific for Ang-II. The rank order of potency of /sup 125/I-Ang-II binding was determined. Scatchard analysis revealed a homogeneous population of high-affinity binding sites with a B/sub max/ of 110 fmol/mg of protein. Light-microscopic autoradiography of /sup 125/I-Ang-II binding supported the kinetic data, documenting specific Ang-II receptors on the glial cells. Ang-II stimulated a dose-dependent hydrolysis of phosphatidylinositols in glial cells, an effect mediated by Ang-II receptors. However, Ang-II failed to influence (/sup 3/H) norepinephrine uptake, and catecholamines failed to regulate Ang-II receptors, effects that occur in neurons. These observations demonstrate the presence of specific Ang-II receptors on the glial cells in primary cultures derived from normotensive rat brain. The receptors are kinetically similar to, but functionally distinct from, the neuronal Ang-II receptors.

  1. Cooperative effect of angiotensin AT(1) and endothelin ET(A) receptor antagonism limits the brain damage after ischemic stroke in rat

    DEFF Research Database (Denmark)

    Stenman, Emelie; Jamali, Roya; Henriksson, Marie;

    2007-01-01

    Cerebral ischemia results in enhanced expression of smooth muscle cell endothelin and angiotensin receptors in cerebral arteries. We hypothesise that this phenomenon may be detrimental and that acute treatment with a combined non-hypotensive dose of the angiotensin AT(1) receptor inhibitor candes...

  2. Angiotensin II receptor mRNA expression and vasoconstriction in human coronary arteries

    DEFF Research Database (Denmark)

    Wackenfors, Angelica; Pantev, Emil; Emilson, Malin;

    2004-01-01

    -induced vasoconstriction diminished with increasing age in patients with heart failure (r(2)=0.31, P<0.05). Also, the AT(1) receptor mRNA expression levels decreased with increasing age in patients with heart failure (r(2)=0.74, P<0.05), while no such correlation could be shown in the control group (r(2)=0.04, P......=n.s.). The AT(2) receptor mRNA expression levels did not correlate with age in patients with heart failure or controls. In conclusion, the diminished angiotensin II vasoconstriction with age in heart failure patients is most likely due to a lower density of AT(1) receptors and may result from a longer period...

  3. Differential involvement of hippocampal angiotensin 1 receptors in learning and memory processes in bulbectomized rats

    Directory of Open Access Journals (Sweden)

    Tashev E. Roman

    2016-04-01

    Full Text Available There is conflicting evidence regarding the effect of AT1 receptor antagonists on learning and memory processes. The effects of angiotensin II and losartan administration into CA1 hippocampal area on the avoidance performance in olfactory bulbectomized (OBX rats using active avoidance (shuttle box test and passive avoidance (step through test were investigated. Rats were microinjected unilaterally through implanted guide cannulas into the CA1 area of the dorsal hippocampus and the drugs were administered separately, 5 minutes before each training session. The microinjections of losartan into the left, but not the right CA1 hippocampal area improved the acquisition and retention of active and passive avoidance learning, thus suggesting dependence on the side of injection. The unilateral (left or right administration of angiotensin II did not significantly affect the performance of OBX rats in the avoidance tasks. A differential distribution of the AT1 receptors in the left and right hemisphere could contribute for the asymmetry in the behavioral effects of the AT receptor antagonist.

  4. Angiotensin AT2 receptor agonist prevents salt-sensitive hypertension in obese Zucker rats

    OpenAIRE

    Ali, Quaisar; Patel, Sanket; Hussain, Tahir

    2015-01-01

    High-sodium intake is a risk factor for the pathogenesis of hypertension, especially in obesity. The present study is designed to investigate whether angiotensin type 2 receptor (AT2R) activation with selective agonist C21 prevents high-sodium diet (HSD)-induced hypertension in obese animals. Male obese rats were treated with AT2R agonist C21 (1 mg·kg−1·day−1, oral) while maintained on either normal-sodium diet (NSD; 0.4%) or HSD (4%) for 2 wk. Radiotelemetric recording showed a time-dependen...

  5. [Duality of angiotensin II receptors and risk for stroke and cancer: what is the connection?].

    Science.gov (United States)

    Fournier, A; Ghitu, A; Darabont, R; Mazouz, H; Makdassi, R; Canaple, S; Rosa, A; Fernandez, L A

    Angiotensin II (AII) acts by 2 types of receptors: the ATI receptor which mediates its actions on vasoconstriction, renin (inhibition) and aldosterone (stimulation) secretions, cellular proliferation and angiogenesis and the non-AT1 (often called AT2) receptors. Mainly expressed in the embryon these latter may favor cellular differentiation and recruitment of collateral circulation. Angiotensin converting enzyme inhibitors (ACEI) decrease the synthesis of All and therefore the stimulation of both receptor types whereas AT1-receptor antagonists (AT1RA) block only the stimulation of these latter and increase the stimulation of AT2 receptor since they increase the production of All secondarily to the inhibition of the feedback of renin secretion by All. Experimentally ACEI and AT1RA decrease angiogenesis and cellular proliferation and favor cellular differentiation which could explain the protective effect of ACEI against cancer suggested recently in a Scotish study. Despite of their common suppressive effect on angiogenesis AT1RA may better than ACEI protect against ischemic events specially the cerebral ones because they favor the rapid recruitment of collateral circulation. This has been demonstrated for losartan in case of abrupt ligation of the carotid in the gerbil since its previous administration protects against fatal cerebral ischemia whereas its previous administration with enalapril abolishes this protection. These data may explain why, in the CAPP trial, captopril which has prevented more effectively diabetes occurrence could not be proved superior to diuretics and/or betablocker in the prevention of myocardial infarction and specially of strokes for which exist on the contrary a suspicion of a lower protection. Therefore a comparative trial between AT1RA and ACEI in the prevention of stroke recurrence should appear as a priority for Public Health and Pharmaceutical Industry Authorities. PMID:10360191

  6. Evidence that the angiotensin at 2-receptor agonist compound 21 is also a low affinity thromboxane TXA2-receptor antagonist

    DEFF Research Database (Denmark)

    Fredgart, M.; Leurgans, T.; Stenelo, M.;

    2015-01-01

    Objective: The objective of this study was to test whether Compound 21 (C21), a high-affinity, non-peptide angiotensinAT2-receptor agonist, is also an antagonist of thromboxane A2 (TXA2) receptors thus reducing both vasoconstriction and platelet aggregation. Design and method: Binding of C21 to the...... TXA2 receptor was determined by TBXA2R Arrestin Biosensor Assay. Mouse mesenteric arteries were mounted in wire myographs, and responses to increasing concentrations of C21 (1nM- 10muM) were recorded during submaximal contractions with 0.1muM U46619 (TXA2 analogue) or 1muMphenylephrine. To control for...

  7. Expression of a naturally occurring angiotensin AT1 receptor cleavage fragment elicits caspase-activation and apoptosis

    OpenAIRE

    Cook, Julia L.; Singh, Akannsha; DeHaro, Dawn; Alam, Jawed; Re, Richard N.

    2011-01-01

    Several transmembrane receptors are documented to accumulate in nuclei, some as holoreceptors and others as cleaved receptor products. Our prior studies indicate that a population of the 7-transmembrane angiotensin type-1 receptor (AT1R) is cleaved in a ligand-augmented manner after which the cytoplasmic, carboxy-terminal cleavage fragment (CF) traffics to the nucleus. In the present report, we determine the precise cleavage site within the AT1R by mass spectrometry and Edman sequencing. Clea...

  8. Structure-Function Basis of Attenuated Inverse Agonism of Angiotensin II Type 1 Receptor Blockers for Active-State Angiotensin II Type 1 Receptor.

    Science.gov (United States)

    Takezako, Takanobu; Unal, Hamiyet; Karnik, Sadashiva S; Node, Koichi

    2015-09-01

    Ligand-independent signaling by the angiotensin II type 1 receptor (AT1R) can be activated in clinical settings by mechanical stretch and autoantibodies as well as receptor mutations. Transition of the AT1R to the activated state is known to lower inverse agonistic efficacy of clinically used AT1R blockers (ARBs). The structure-function basis for reduced efficacy of inverse agonists is a fundamental aspect that has been understudied not only in relation to the AT1R but also regarding other homologous receptors. Here, we demonstrate that the active-state transition in the AT1R indeed attenuates an inverse agonistic effect of four biphenyl-tetrazole ARBs through changes in specific ligand-receptor interactions. In the ground state, tight interactions of four ARBs with a set of residues (Ser109(TM3), Phe182(ECL2), Gln257(TM6), Tyr292(TM7), and Asn295(TM7)) results in potent inverse agonism. In the activated state, the ARB-AT1R interactions shift to a different set of residues (Val108(TM3), Ser109(TM3), Ala163(TM4), Phe182(ECL2), Lys199(TM5), Tyr292(TM7), and Asn295(TM7)), resulting in attenuated inverse agonism. Interestingly, V108I, A163T, N295A, and F182A mutations in the activated state of the AT1R shift the functional response to the ARB binding toward agonism, but in the ground state the same mutations cause inverse agonism. Our data show that the second extracellular loop is an important regulator of the functional states of the AT1R. Our findings suggest that the quest for discovering novel ARBs, and improving current ARBs, fundamentally depends on the knowledge of the unique sets of residues that mediate inverse agonistic potency in the two states of the AT1R. PMID:26121982

  9. ANGIOTENSIN I CONVERTING ENZYME GENE POLYMORPHISM AND EXERCISE TRAINABILITY IN ELDERLY WOMEN: AN ELECTROCARDIOLOGICAL APPROACH

    OpenAIRE

    Takuro Tobina; Akira Kiyonaga; Yuko Akagi; Yukari Mori; Kojiro Ishii; Hitoshi Chiba; Munehiro Shindo; Hiroaki Tanaka

    2007-01-01

    Angiotensin I converting enzyme (ACE) gene Insertion / Deletion (I/D) polymorphism is associated with exercise trainability and exercise induced left ventricular hypertrophy. However, it is unclear whether this polymorphism influences exercise trainability in the elderly, and the electrocardiological alterations by exercise training is unknown among the genotypes. We herein investigated the association between ACE gene insertion/deletion (I/D) polymorphism, exercise trainability and the elect...

  10. The angiotensin-converting enzyme (ACE) gene family of Anopheles gambiae.

    OpenAIRE

    Isaac R Elwyn; Lee Alison J; Smith Judith A; Burnham Susan; Shirras Alan D

    2005-01-01

    Abstract Background Members of the M2 family of peptidases, related to mammalian angiotensin converting enzyme (ACE), play important roles in regulating a number of physiological processes. As more invertebrate genomes are sequenced, there is increasing evidence of a variety of M2 peptidase genes, even within a single species. The function of these ACE-like proteins is largely unknown. Sequencing of the A. gambiae genome has revealed a number of ACE-like genes but probable errors in the Ensem...

  11. AT1a Receptor Has Interacted with Angiotensin-converting Enzymes 2 mRNA Expression in Mouse Brainstem

    Institute of Scientific and Technical Information of China (English)

    Zhanyi Lin; Shuguang Lin

    2008-01-01

    Objectives To examine in vivo interactions between angiotensin Ⅱ(Ang Ⅱ) AT1a receptor (AT1aR),angiotensin-converting enzymes (ACE) and ACE2 using small hairpin RNA (shRNA) gene-silencing methods in mice brainstem nucleus ttactus solitarius (NTS).Methods C57BL mice (n=8) were used as animal model.Method of microinjection in the nucleus of NTS was adopted.After ten days,mice were killed and their brain tissue were fixed and sectioned.The expression levels of AT1 aR,ACE and ACE2 mRNA at both sides of NTS were examined by in situ hybridization.Based on compared t-test,the changing for mRNA expression was examined.Results After the expression of AT1aR mRNA was significantly inhibited (61.6%±6.8% ) by AT1aR-shRNA,it was associated with decreases in ACE2 mRNA expression from (1.05±0.12) μCi/mg to (0.74±0.09) μCi/mg (29.0%±14.5%,P<0.01) on the same side of the brainstem.ACE mRNA expression was consistent at both sides (0.50 μCi/mg±0.09 μCi/mg and 0.53 μCi/mg±0.08 μCi/mg),with insignificant difference (P>0.05).Condusions The gene silencing result showed that there were interactions between brainstem AT1aR and ACE2.ACE mRNA expression was not altered by RNA interference treatment at AT1aR.

  12. Rational Design, Efficient Synthesis, Biological Evaluation of New Ν,Ν'-bis-substituted Butylimidazole Analogs as Potent Angiotensin Receptor Blockers

    Czech Academy of Sciences Publication Activity Database

    Agelis, G.; Resvani, A.; Koukoulitsa, C.; Afantitis, A.; Melagraki, G.; Siafaka, A.; Gkini, E.; Tůmová, Tereza; Spyridaki, K.; Kalavrizioti, D.; Androutsou, M-E.; Slaninová, Jiřina; Liapakis, G.; Vlahakos, D.; Mavromoustakos, T.; Matsoukas, J.

    2012-01-01

    Roč. 18, S1 (2012), S123-S123. ISSN 1075-2617. [European Peptide Symposium /32./. 02.09.2012-07.09.2012, Athens] Institutional research plan: CEZ:AV0Z40550506 Keywords : angiotensin II AT1 receptor * in vitro * antagonism * inhibitor * in vitro antagonism * synthesis Subject RIV: CE - Biochemistry

  13. Increased expression of vascular endothelin type B and angiotensin type 1 receptors in patients with ischemic heart disease

    DEFF Research Database (Denmark)

    Dimitrijevic, Ivan; Edvinsson, Lars; Chen, Qingwen; Malmsjö, Malin; Kimblad, Per-Ola

    2009-01-01

    pectoris without established myocardial infarction (n = 15) and matched cardiovascular healthy controls (n = 15). Endothelin type A (ETA) and type B (ETB), and angiotensin type 1 (AT1) and type 2 (AT2) receptors expression and function were examined using immunohistochemistry, Western blot and in vitro...

  14. Nitric oxide up-regulates endothelial expression of angiotensin II type 2 receptors.

    Science.gov (United States)

    Dao, Vu Thao-Vi; Medini, Sawsan; Bisha, Marion; Balz, Vera; Suvorava, Tatsiana; Bas, Murat; Kojda, Georg

    2016-07-15

    Increasing vascular NO levels following up-regulation of endothelial nitric oxide synthase (eNOS) is considered beneficial in cardiovascular disease. Whether such beneficial effects exerted by increased NO-levels include the vascular renin-angiotensin system remains elucidated. Exposure of endothelial cells originated from porcine aorta, mouse brain and human umbilical veins to different NO-donors showed that expression of the angiotensin-II-type-2-receptor (AT2) mRNA and protein is up-regulated by activation of soluble guanylyl cyclase, protein kinase G and p38 mitogen-activated protein kinase without changing AT2 mRNA stability. In mice, endothelial-specific overexpression of eNOS stimulated, while chronic treatment with the NOS-blocker l-nitroarginine inhibited AT2 expression. The NO-induced AT2 up-regulation was associated with a profound inhibition of angiotensin-converting enzyme (ACE)-activity. In endothelial cells this reduction of ACE-activity was reversed by either the AT2 antagonist PD 123119 or by inhibition of transcription with actinomycin D. Furthermore, in C57Bl/6 mice an acute i.v. bolus of l-nitroarginine did not change AT2-expression and ACE-activity suggesting that inhibition of ACE-activity by endogenous NO is crucially dependent on AT2 protein level. Likewise, three weeks of either voluntary or forced exercise training increased AT2 expression and reduced ACE-activity in C57Bl/6 but not in mice lacking eNOS suggesting significance of this signaling interaction for vascular physiology. Finally, aortic AT2 expression is about 5 times greater in female as compared to male C57Bl/6 and at the same time aortic ACE activity is reduced in females by more than 50%. Together these findings imply that endothelial NO regulates AT2 expression and that AT2 may regulate ACE-activity. PMID:27235748

  15. Angiotensin-2-mediated Ca2+ signaling in the retinal pigment epithelium: role of angiotensin-receptor-associated-protein and TRPV2 channel.

    Directory of Open Access Journals (Sweden)

    Rene Barro-Soria

    Full Text Available Angiotensin II (AngII receptor (ATR is involved in pathologic local events such as neovascularisation and inflammation including in the brain and retina. The retinal pigment epithelium (RPE expresses ATR in its AT1R form, angiotensin-receptor-associated protein (Atrap, and transient-receptor-potential channel-V2 (TRPV2. AT1R and Atrap co-localize to the basolateral membrane of the RPE, as shown by immunostaining. Stimulation of porcine RPE (pRPE cells by AngII results in biphasic increases in intracellular free Ca(2+inhibited by losartan. Xestospongin C (xest C and U-73122, blockers of IP3R and PLC respectively, reduced AngII-evoked Ca(2+response. RPE cells from Atrap(-/- mice showed smaller AngII-evoked Ca(2+peak (by 22% and loss of sustained Ca(2+elevation compared to wild-type. The TRPV channel activator cannabidiol (CBD at 15 µM stimulates intracellular Ca(2+-rise suggesting that porcine RPE cells express TRPV2 channels. Further evidence supporting the functional expression of TRPV2 channels comes from experiments in which 100 µM SKF96365 (a TRPV channel inhibitor reduced the cannabidiol-induced Ca(2+-rise. Application of SKF96365 or reduction of TRPV2 expression by siRNA reduced the sustained phase of AngII-mediated Ca(2+transients by 53%. Thus systemic AngII, an effector of the local renin-angiotensin system stimulates biphasic Ca(2+transients in the RPE by releasing Ca(2+from cytosolic IP3-dependent stores and activating ATR/Atrap and TRPV2 channels to generate a sustained Ca(2+elevation.

  16. Pharmacological characterization of BR-A-657, a highly potent nonpeptide angiotensin II receptor antagonist

    International Nuclear Information System (INIS)

    The pharmacological profile of BR-A-657, 2-n-butyl-5-dimethylamino-thiocarbonyl-methyl-6-methyl-3 - {[2-(1H-tetrazole-5-yl)biphenyl-4-yl]methyl} - pyrimidin-4(3H)-one, a new nonpeptide AT1-selective angiotensin receptor antagonist, has been investigated in a variety of in vitro and in vivo experimental models. In the present study, BR-A-657 displaced [125I][Sar1-Ile8]angiotensin II (Ang II) from its specific binding sites to AT1 subtype receptors in membrane fractions of HEK-293 cells with an IC50 of 0.16 nM. In a functional assay using isolated rabbit thoracic aorta, BR-A-657 inhibited the contractile response to Ang II (pD'2: 9.15) with a significant reduction in the maximum. In conscious rats, BR-A-657 (0.01, 0.1, 1 mg/kg; intravenously (i.v.)) dose-dependently antagonized Ang II-induced pressor responses. In addition, BR-A-657 dose-dependently decreased mean arterial pressure in furosemide-treated rats and renal hypertensive rats. Moreover, BR-A-657 given orally at 1 and 3 mg/kg reduced blood pressure in conscious renal hypertensive rats. Taken together, these findings indicate that BR-A-657 is a potent and specific antagonist of Ang II at the AT1 receptor subtype, and reveal the molecular basis responsible for the marked lowering of blood pressure in conscious rats. (author)

  17. Postprandial fatty acid uptake and adipocyte remodeling in angiotensin type 2 receptor-deficient mice fed a high-fat/high-fructose diet.

    Science.gov (United States)

    Noll, Christophe; Labbé, Sébastien M; Pinard, Sandra; Shum, Michael; Bilodeau, Lyne; Chouinard, Lucie; Phoenix, Serge; Lecomte, Roger; Carpentier, André C; Gallo-Payet, Nicole

    2016-01-01

    The role of the angiotensin type-2 receptor in adipose physiology remains controversial. The aim of the present study was to demonstrate whether genetic angiotensin type-2 receptor-deficiency prevents or worsens metabolic and adipose tissue morphometric changes observed following a 6-week high-fat/high-fructose diet with injection of a small dose of streptozotocin. We compared tissue uptake of nonesterified fatty acid and dietary fatty acid in wild-type and angiotensin type-2 receptor-deficient mice by using the radiotracer 14(R,S)-[(1) (8)F]-fluoro-6-thia-heptadecanoic acid in mice fed a standard or high-fat diet. Postprandial fatty acid uptake in the heart, liver, skeletal muscle, kidney and adipose tissue was increased in wild-type mice after a high-fat diet and in angiotensin type-2 receptor-deficient mice on both standard and high-fat diets. Compared to the wild-type mice, angiotensin type-2 receptor-deficient mice had a lower body weight, an increase in fasting blood glucose and a decrease in plasma insulin and leptin levels. Mice fed a high-fat diet exhibited increased adipocyte size that was prevented by angiotensin type-2 receptor-deficiency. Angiotensin type-2 receptor-deficiency abolished the early hypertrophic adipocyte remodeling induced by a high-fat diet. The small size of adipocytes in the angiotensin type-2 receptor-deficient mice reflects their inability to store lipids and explains the increase in fatty acid uptake in non-adipose tissues. In conclusion, a genetic deletion of the angiotensin type-2 receptor is associated with metabolic dysfunction of white adipose depots, and indicates that adipocyte remodeling occurs before the onset of insulin resistance in the high-fat fed mouse model. PMID:27144096

  18. Functional interaction between angiotensin II receptor type 1 and chemokine (C-C Motif) receptor 2 with implications for chronic kidney disease

    OpenAIRE

    Mohammed Akli Ayoub; Yuan Zhang; Kelly, Robyn S.; Heng B See; Johnstone, Elizabeth K.M.; McCall, Elizabeth A.; Williams, James H; Kelly, Darren J.; Pfleger, Kevin D.G.

    2015-01-01

    Understanding functional interactions between G protein-coupled receptors is of great physiological and pathophysiological importance. Heteromerization provides one important potential mechanism for such interaction between different signalling pathways via macromolecular complex formation. Previous studies suggested a functional interplay between angiotensin II receptor type 1 (AT1) and Chemokine (C-C motif) Receptor 2 (CCR2). However the molecular mechanisms are not understood. We investiga...

  19. The influence of certain molecular descriptors of fecal elimination of angiotensin II receptor antagonists

    Directory of Open Access Journals (Sweden)

    Trbojević-Stanković Jasna B.

    2015-01-01

    Full Text Available Angiotensin II receptor antagonists (ARBs modulate the function of the renin-angiotensin-aldosterone system and are commonly prescribed antihypertensive drugs, especially in patients with renal failure. In this study, the relationship between several molecular properties of seven ARBs (candesartan, eprosartan, irbesartan, losartan, olmesartan, telmisartan, valsartan and their fecal elimination data obtained from the literature were investigated. The ARB molecular descriptors were calculated using three software packages. Simple linear regression analysis showed the best 2 correlation between fecal elimination data and lipophilicity descriptor, ClogP values (R2 = 0.725. Multiple linear regression was applied to examine the correlation of ARBs’ fecal elimination data with their lipophilicity and one additional, calculated descriptor. The best correlation (R2 = 0.909 with an acceptable probability value, P <0.05 was established between the ARB fecal elimination data and their lipophilicity and aqueous solubility data. Applying computed molecular descriptors for evaluating drug elimination is of great importance in drug research.

  20. CORRECTION OF ENDOTHELIAL DYSFUNCTION IN PATIENTS WITH CHRONIC COR PULMONALE BY ANGIOTENSIN II RECEPTORS ANTAGONISTS

    Directory of Open Access Journals (Sweden)

    V. S. Zadionchenko

    2015-12-01

    Full Text Available Aim. To evaluate intensity of endothelial dysfunction, processes of apoptosis, state of central and peripheral hemodynamics and to evaluate how these characteristics are influenced by angiotensin II receptors antagonists (ARA II – candesartan (Atacand and losartan (Cosaar in patients with chronic cor pulmonale (CCP at different stages of disease.Material and methods. 100 patients with chronic obstructive pulmonary disease (COPD, complicated by CCP were included into the study. Caspase activity as apoptosis induction marker, von Willebrand factor, production of nitric oxide in blood plasma and condensate of breathing out air were assessed. 70 patients received ARA II (50 patients – candesartan 4-8 mg daily, 20 patients – losartan 50-100 mg daily, 30 patients received neither ARA II nor angiotensin converting enzyme inhibitors (ACEI.Results. Significant increase in intensity of endothelial dysfunction and activation of apoptosis processes were registered according to growth of CCP severity. After 6 months of therapy von Willebrand factor decreased by 25,2% and 27,7% in candesartan and losartan groups respectively (p<0.01 for both groups. In the control group only 13.2% of von Willebrand factor reduction was seen.Conclusion. ARA II added to common therapy of COPD complicated by CCP improves functional state of endothelium restricting hyperproduction of nitric oxide and its toxic effects and slowing down apoptotic cell death.

  1. Angiotensin II type 1 receptor signalling regulates microRNA differentially in cardiac fibroblasts and myocytes

    DEFF Research Database (Denmark)

    Jeppesen, Pia Lindgren; Christensen, Gitte Lund; Schneider, Mikael; Nossent, Anne Yaël; Jensen, Hasse Brønnum; Andersen, Ditte Caroline; Eskildsen, Tilde; Gammeltoft, Steen; Hansen, Jakob Lerche; Sheikh, Søren Paludan

    2011-01-01

    Background and purpose: The Angiotensin II type 1 receptor (AT(1) R) is a key regulator of blood pressure and cardiac contractility and is profoundly involved in development of cardiac disease. Since several microRNAs (miRNAs) have been implicated in cardiac disease, we asked whether miRNAs might...... be regulated by AT(1) R signals in a Gaq/11 dependent or -independent manner. Experimental approach: We performed a global miRNA array analysis of angiotensin II (Ang II) mediated miRNA regulation in HEK293N cells over-expressing the AT(1) R and focused on separating the role of Gaq/11 -dependent and...... -independent pathways. MiRNA regulation was verified with quantitative PCR in both HEK293N cells and primary cardiac myocytes and fibroblasts. Key results: Our studies revealed five miRNAs (miR-29b, -129-3p, -132, -132* and -212) that were upregulated by Ang II in HEK293N cells. In contrast, the biased Ang II...

  2. Aspirin suppresses cardiac fibroblast proliferation and collagen formation through downregulation of angiotensin type 1 receptor transcription

    International Nuclear Information System (INIS)

    Aspirin (acetyl salicylic acid, ASA) is a common drug used for its analgesic and antipyretic effects. Recent studies show that ASA not only blocks cyclooxygenase, but also inhibits NADPH oxidase and resultant reactive oxygen species (ROS) generation, a pathway that underlies pathogenesis of several ailments, including hypertension and tissue remodeling after injury. In these disease states, angiotensin II (Ang II) activates NADPH oxidase via its type 1 receptor (AT1R) and leads to fibroblast growth and collagen synthesis. In this study, we examined if ASA would inhibit NADPH oxidase activation, upregulation of AT1R transcription, and subsequent collagen generation in mouse cardiac fibroblasts challenged with Ang II. Mouse heart fibroblasts were isolated and treated with Ang II with or without ASA. As expected, Ang II induced AT1R expression, and stimulated cardiac fibroblast growth and collagen synthesis. The AT1R blocker losartan attenuated these effects of Ang II. Similarly to losartan, ASA, and its SA moiety suppressed Ang II-mediated AT1R transcription and fibroblast proliferation as well as expression of collagens and MMPs. ASA also suppressed the expression of NADPH oxidase subunits (p22phox, p47phox, p67phox, NOX2 and NOX4) and ROS generation. ASA did not affect total NF-κB p65, but inhibited its phosphorylation and activation. These observations suggest that ASA inhibits Ang II-induced NADPH oxidase expression, NF-κB activation and AT1R transcription in cardiac fibroblasts, and fibroblast proliferation and collagen expression. The critical role of NADPH oxidase activity in stimulation of AT1R transcription became apparent in experiments where ASA also inhibited AT1R transcription in cardiac fibroblasts challenged with H2O2. Since SA had similar effect as ASA on AT1R expression, we suggest that ASA's effect is mediated by its SA moiety. -- Highlights: ► Aspirin in therapeutic concentrations decreases mouse cardiac fibroblast growth and collagen formation

  3. Aspirin suppresses cardiac fibroblast proliferation and collagen formation through downregulation of angiotensin type 1 receptor transcription

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xianwei, E-mail: XWang2@UAMS.edu; Lu, Jingjun; Khaidakov, Magomed; Mitra, Sona; Ding, Zufeng; Raina, Sameer; Goyal, Tanu; Mehta, Jawahar L., E-mail: MehtaJL@UAMS.edu

    2012-03-15

    Aspirin (acetyl salicylic acid, ASA) is a common drug used for its analgesic and antipyretic effects. Recent studies show that ASA not only blocks cyclooxygenase, but also inhibits NADPH oxidase and resultant reactive oxygen species (ROS) generation, a pathway that underlies pathogenesis of several ailments, including hypertension and tissue remodeling after injury. In these disease states, angiotensin II (Ang II) activates NADPH oxidase via its type 1 receptor (AT1R) and leads to fibroblast growth and collagen synthesis. In this study, we examined if ASA would inhibit NADPH oxidase activation, upregulation of AT1R transcription, and subsequent collagen generation in mouse cardiac fibroblasts challenged with Ang II. Mouse heart fibroblasts were isolated and treated with Ang II with or without ASA. As expected, Ang II induced AT1R expression, and stimulated cardiac fibroblast growth and collagen synthesis. The AT1R blocker losartan attenuated these effects of Ang II. Similarly to losartan, ASA, and its SA moiety suppressed Ang II-mediated AT1R transcription and fibroblast proliferation as well as expression of collagens and MMPs. ASA also suppressed the expression of NADPH oxidase subunits (p22{sup phox}, p47{sup phox}, p67{sup phox}, NOX2 and NOX4) and ROS generation. ASA did not affect total NF-κB p65, but inhibited its phosphorylation and activation. These observations suggest that ASA inhibits Ang II-induced NADPH oxidase expression, NF-κB activation and AT1R transcription in cardiac fibroblasts, and fibroblast proliferation and collagen expression. The critical role of NADPH oxidase activity in stimulation of AT1R transcription became apparent in experiments where ASA also inhibited AT1R transcription in cardiac fibroblasts challenged with H{sub 2}O{sub 2}. Since SA had similar effect as ASA on AT1R expression, we suggest that ASA's effect is mediated by its SA moiety. -- Highlights: ► Aspirin in therapeutic concentrations decreases mouse cardiac

  4. Melatonin Receptor Genes in Vertebrates

    Directory of Open Access Journals (Sweden)

    Hua Dong Yin

    2013-05-01

    Full Text Available Melatonin receptors are members of the G protein-coupled receptor (GPCR family. Three genes for melatonin receptors have been cloned. The MT1 (or Mel1a or MTNR1A and MT2 (or Mel1b or MTNR1B receptor subtypes are present in humans and other mammals, while an additional melatonin receptor subtype, Mel1c (or MTNR1C, has been identified in fish, amphibians and birds. Another melatonin related orphan receptor, GPR50, which does not bind melatonin, is found exclusively in mammals. The hormone melatonin is secreted primarily by the pineal gland, with highest levels occurring during the dark period of a circadian cycle. This hormone acts systemically in numerous organs. In the brain, it is involved in the regulation of various neural and endocrine processes, and it readjusts the circadian pacemaker, the suprachiasmatic nucleus. This article reviews recent studies of gene organization, expression, evolution and mutations of melatonin receptor genes of vertebrates. Gene polymorphisms reveal that numerous mutations are associated with diseases and disorders. The phylogenetic analysis of receptor genes indicates that GPR50 is an outgroup to all other melatonin receptor sequences. GPR50 may have separated from a melatonin receptor ancestor before the split between MTNR1C and the MTNR1A/B ancestor.

  5. Enhanced water and salt intake in transgenic mice with brain-restricted overexpression of angiotensin (AT1) receptors

    OpenAIRE

    Lazartigues, Eric; Sinnayah, Puspha; Augoyard, Ginette; Gharib, Claude; Johnson, Alan Kim; Davisson, Robin L.

    2008-01-01

    To address the relative contribution of central and peripheral angiotensin II (ANG II) type 1A receptors (AT1A) to blood pressure and volume homeostasis, we generated a transgenic mouse model [neuron-specific enolase (NSE)-AT1A] with brain-restricted overexpression of AT1A receptors. These mice are normotensive at baseline but have dramatically enhanced pressor and bradycardic responses to intracerebroventricular ANG II or activation of endogenous ANG II production. Here our goal was to exami...

  6. Blockade of brain angiotensin II AT1 receptors ameliorates stress, anxiety, brain inflammation and ischemia: Therapeutic implications.

    Science.gov (United States)

    Saavedra, Juan M; Sánchez-Lemus, Enrique; Benicky, Julius

    2011-01-01

    Poor adaptation to stress, alterations in cerebrovascular function and excessive brain inflammation play critical roles in the pathophysiology of many psychiatric and neurological disorders such as major depression, schizophrenia, post traumatic stress disorder, Parkinson's and Alzheimer's diseases and traumatic brain injury. Treatment for these highly prevalent and devastating conditions is at present very limited and many times inefficient, and the search for novel therapeutic options is of major importance. Recently, attention has been focused on the role of a brain regulatory peptide, Angiotensin II, and in the translational value of the blockade of its physiological AT(1) receptors. In addition to its well-known cardiovascular effects, Angiotensin II, through AT(1) receptor stimulation, is a pleiotropic brain modulatory factor involved in the control of the reaction to stress, in the regulation of cerebrovascular flow and the response to inflammation. Excessive brain AT(1) receptor activity is associated with exaggerated sympathetic and hormonal response to stress, vulnerability to cerebrovascular ischemia and brain inflammation, processes leading to neuronal injury. In animal models, inhibition of brain AT(1) receptor activity with systemically administered Angiotensin II receptor blockers is neuroprotective; it reduces exaggerated stress responses and anxiety, prevents stress-induced gastric ulcerations, decreases vulnerability to ischemia and stroke, reverses chronic cerebrovascular inflammation, and reduces acute inflammatory responses produced by bacterial endotoxin. These effects protect neurons from injury and contribute to increase the lifespan. Angiotensin II receptor blockers are compounds with a good margin of safety widely used in the treatment of hypertension and their anti-inflammatory and vascular protective effects contribute to reduce renal and cardiovascular failure. Inhibition of brain AT(1) receptors in humans is also neuroprotective

  7. Expression of Astrocytic Type 2 Angiotensin Receptor in Central Nervous System Inflammation Correlates With Blood-Brain Barrier Breakdown

    DEFF Research Database (Denmark)

    Füchtbauer, Laila; Toft-Hansen, Henrik; Khorooshi, Reza;

    2010-01-01

    The blood-brain barrier (BBB), a complex of endothelial and glial barriers, controls passage of cells and solutes between the blood and central nervous system (CNS). Blood-brain barrier breakdown refers to entry of cells and/or solutes. We were interested whether the renin-angiotensin system is...... involved during BBB breakdown. We studied the type 2 angiotensin receptor AT(2) because of its suggested neuroprotective role. Two models of brain inflammation were used to distinguish solute versus cellular barrier functions. Both leukocytes and horseradish peroxidase (HRP) accumulated in the perivascular...

  8. Angiotensin-converting enzyme gene and retinal arteriolar narrowing: The Funagata Study

    OpenAIRE

    Tanabe, Y; Kawasaki, R.; J. J. Wang; Wong, T Y; Mitchell, P; Daimon, M; Oizumi, T; Kato, T.; Kawata, S.; Kayama, T; Yamashita, H.

    2009-01-01

    The purpose of this study is to determine whether the angiotensin-converting enzyme (ACE) gene polymorphism is associated with retinal arteriolar narrowing, a subclinical marker of chronic hypertension. The Funagata Study examined a population-based sample of Japanese aged 35+ years; 368 participants had both retinal vessel diameter measurements and ACE insertion/deletion (ACE I/D) polymorphism analyses performed. Assessment of retinal vessel diameter and retinal vessel wall signs followed th...

  9. Role of angiotensin converting enzyme inhibitors and angiotensin receptor blockers in hypertension of chronic kidney disease and renoprotection. Study results

    OpenAIRE

    Baltatzi, M; Savopoulos, Ch; Hatzitolios, A

    2011-01-01

    Chronic kidney disease (CKD) is a global health problem associated with considerable morbidity and mortality and despite advances in the treatment of end stage renal disease (ESRD) mechanisms to prevent and delay its progression are still being sought. The renin-angiotensin-aldosterone system (RAAS) plays a pivotal role in many of the pathophysiologic changes that lead to progression of renal disease. Traditionally RAAS was considered as an endocrine system and its principal role was to maint...

  10. Expression and transport of Angiotensin II AT1 receptors in spinal cord, dorsal root ganglia and sciatic nerve of the rat

    OpenAIRE

    Pavel, Jaroslav; Tang, Hui; Brimijoin, Stephen; Moughamian, Armen; Nishioku, Tsuyoshi; Benicky, Julius; Saavedra, Juan M.

    2008-01-01

    To clarify the role of Angiotensin II in the regulation of peripheral sensory and motor systems, we initiated a study of the expression, localization and transport of Angiotensin II receptor types in the rat sciatic nerve pathway, including L4–L5 spinal cord segments, the corresponding dorsal root ganglia (DRGs) and the sciatic nerve.

  11. [Angiotensin-receptor- and neprilysin-inhibition: a new option against heart failure].

    Science.gov (United States)

    Bruhn, Claudia

    2016-01-01

    The molecular combination of sacubitril and valsartan (Entresto) is a new drug for reducing the risk of cardiovascular death and hospitalization for heart failure in patients with chronic heart failure (NYHA Class II-IV) and reduced ejection fraction. It is usually administered in conjunction with other heart failure therapies, instead of an ACE inhibitor or an angiotensin-receptor blocker (ARB). In studies, sacubitril/ valsartan was superior to enalapril in reducing the risks of death and hospitalization for heart failure. Possible side effects of sacubitril/valsartan are hypotension, angioedema, impaired renal function and elevation in serum potassium levels. The drug should not be used in times of pregnancy and breast feeding, in patients with servere hepatic impairment (Child-Pugh C) and in combination with aliskiren in patients with diabetes. PMID:26975167

  12. Efficacy and safety of the angiotensin II receptor blocker losartan for hypertrophic cardiomyopathy

    DEFF Research Database (Denmark)

    Axelsson, Anna; Iversen, Kasper; Vejlstrup, Niels;

    2015-01-01

    18 years and older) with obstructive or non-obstructive hypertrophic cardiomyopathy were randomly assigned via computer-based system to losartan (100 mg per day) or placebo for 12 months. Patients and investigators were masked to assigned treatment. The primary endpoint was change in left ventricular......, and May 1, 2013, 318 patients were screened. 133 patients (mean age 52 years [SD 13], 35% women) consented and were randomly assigned to placebo (n=69) or losartan (n=64). 124 (93%) patients completed the study and were included in the modified intention-to-treat analysis for the primary endpoint...... predictive of an adverse outcome. We aimed to assess the effect of the angiotensin II receptor blocker losartan on left ventricular hypertrophy and fibrosis in patients with hypertrophic cardiomyopathy. METHODS: In this single-centre, randomised, double-blind, placebo-controlled trial, adult patients (aged...

  13. Angiopoietin-like protein 2 expression is suppressed by angiotensin II via the angiotensin II type 1 receptor in rat cardiomyocytes

    Science.gov (United States)

    Wang, Shuya; Li, Ying; Miao, Wei; Zhao, Hong; Zhang, Feng; Liu, Nan; Su, Guohai; Cai, Xiaojun

    2016-01-01

    The present study aimed to determine the inhibitory effects of angiotensin II (AngII) on angiopoietin-like protein 2 (Angptl2) in rat primary cardiomyocytes, and to investigate the potential association between angiotensin II type 1 receptor (AT1R) and these effects. Cardiomyocytes were isolated from 3-day-old Wistar rats, and were cultured and identified. Subsequently, the expression levels of Angptl2 were detected following incubation with various concentrations of AngII for various durations using western blotting, reverse transcription-quantitative polymerase chain reaction, enzyme-linked immunosorbent assay and immunofluorescence. Finally, under the most appropriate conditions (100 nmol/l AngII, 24 h), the cardiomyocytes were divided into six groups: Normal, AngII, AngII + losartan, normal + losartan, AngII + PD123319 and normal + PD123319 groups, in order to investigate the possible function of AT1R in Angptl2 suppression. Losartan and PD123319 are antagonists of AT1R and angiotensin II type 2 receptor, respectively. The statistical significance of the results was analyzed using Student's t-test or one-way analysis of variance. The results demonstrated that Angptl2 expression was evidently suppressed (P<0.05) following incubation with 100 nmol/l AngII for 24 h. Conversely, the expression levels of Angptl2 were significantly increased in the AngII + losartan group compared with the AngII group (P<0.01). However, no significant difference was detected between the AngII + PD123319, normal + losartan or normal + PD123319 groups and the normal group. The present in vitro study indicated that AngII was able to suppress Angptl2 expression, whereas losartan was able to significantly reverse this decrease by inhibiting AT1R. PMID:27483989

  14. ACE inhibition is superior to angiotensin receptor blockade for renography in renal artery stenosis

    Energy Technology Data Exchange (ETDEWEB)

    Karanikas, Georgios; Becherer, Alexander; Wiesner, Karoline; Dudczak, Robert; Kletter, Kurt [Department of Nuclear Medicine, University of Vienna (Austria)

    2002-03-01

    Angiotensin converting enzyme (ACE) inhibitors as well as angiotensin II receptor antagonists are able to prevent the vasoconstrictive effect of angiotensin II on the efferent renal vessels, which is believed to play an important role in renovascular hypertension. This effect is assumed to be essential for the demonstration of renovascular hypertension by captopril renography. In this study, renographic changes induced by captopril and the AT1 receptor antagonist valsartan were compared in patients with a high probability for renovascular hypertension. Twenty-five patients with 33 stenosed renal arteries (grade of stenosis >50%) and hypertension were studied. Captopril, valsartan and baseline renography were performed within 48 h using technetium-99m mercaptoacetyltriglycine. Blood pressure was monitored, plasma renin concentration before and after intervention was determined and urinary flow was estimated from the urinary output of the hydrated patients. Alterations in renographic curves after intervention were evaluated according to the Santa Fe consensus on ACE inhibitor renography. Captopril renography was positive, indicating renovascular hypertension, in 25 of the 33 stenosed vessels, whereas valsartan renography was positive in only ten. Blood pressure during captopril and valsartan renography was not different; reduction in blood pressure was the same after valsartan and captopril. Plasma renin concentration was comparable for valsartan and captopril studies, showing suppressed values after intervention in as many as 12 of the 25 patients. Urinary flow after valsartan was higher than after captopril (P<0.05). However, this difference could not explain the markedly higher sensitivity of captopril compared with valsartan in demonstrating renal artery stenosis. In 14 of the 25 patients, blood pressure response to revascularisation was monitored, showing a much better predictive value for captopril renography. It is concluded that captopril renography is much

  15. Angiotensin II AT(1) receptor blockers as treatments for inflammatory brain disorders.

    Science.gov (United States)

    Saavedra, Juan M

    2012-11-01

    The effects of brain AngII (angiotensin II) depend on AT(1) receptor (AngII type 1 receptor) stimulation and include regulation of cerebrovascular flow, autonomic and hormonal systems, stress, innate immune response and behaviour. Excessive brain AT(1) receptor activity associates with hypertension and heart failure, brain ischaemia, abnormal stress responses, blood-brain barrier breakdown and inflammation. These are risk factors leading to neuronal injury, the incidence and progression of neurodegerative, mood and traumatic brain disorders, and cognitive decline. In rodents, ARBs (AT(1) receptor blockers) ameliorate stress-induced disorders, anxiety and depression, protect cerebral blood flow during stroke, decrease brain inflammation and amyloid-β neurotoxicity and reduce traumatic brain injury. Direct anti-inflammatory protective effects, demonstrated in cultured microglia, cerebrovascular endothelial cells, neurons and human circulating monocytes, may result not only in AT(1) receptor blockade, but also from PPARγ (peroxisome-proliferator-activated receptor γ) stimulation. Controlled clinical studies indicate that ARBs protect cognition after stroke and during aging, and cohort analyses reveal that these compounds significantly reduce the incidence and progression of Alzheimer's disease. ARBs are commonly used for the therapy of hypertension, diabetes and stroke, but have not been studied in the context of neurodegenerative, mood or traumatic brain disorders, conditions lacking effective therapy. These compounds are well-tolerated pleiotropic neuroprotective agents with additional beneficial cardiovascular and metabolic profiles, and their use in central nervous system disorders offers a novel therapeutic approach of immediate translational value. ARBs should be tested for the prevention and therapy of neurodegenerative disorders, in particular Alzheimer's disease, affective disorders, such as co-morbid cardiovascular disease and depression, and traumatic

  16. Vascular hypothesis revisited: Role of stimulating antibodies against angiotensin and endothelin receptors in the pathogenesis of systemic sclerosis.

    Science.gov (United States)

    Cabral-Marques, Otavio; Riemekasten, Gabriela

    2016-07-01

    Systemic sclerosis (SSc) is a connective tissue disorder of unknown etiology characterized by the presence of multiple autoantibodies, including those against angiotensin and endothelin receptors. Patients with SSc can develop heterogeneous clinical manifestations including microvascular damage, the dysregulation of innate and adaptive immunity, and generalized fibrosis of multiple organs. Autoantibodies against angiotensin II type I receptor (AT1R) and endothelin-1 type A receptor (ETAR) play important roles in the pathogenesis of SSc. These autoantibodies regulate physiological processes ranging from production of collagen by skin fibroblasts to angiogenesis modulation. Understanding the mechanisms behind autoantibodies against AT1R and ETAR could provide insight to future novel therapies for SSc patients. In this review, we focus on elucidating the immunopathological mechanisms triggered by anti-AT1R and anti-ETAR autoantibodies to summarize current knowledge about vascular abnormalities resulting in progressive damage of organs seen in patients with SSc. PMID:26970493

  17. Relaxin requires the angiotensin II type 2 receptor to abrogate renal interstitial fibrosis.

    Science.gov (United States)

    Chow, Bryna S Man; Kocan, Martina; Bosnyak, Sanja; Sarwar, Mohsin; Wigg, Belinda; Jones, Emma S; Widdop, Robert E; Summers, Roger J; Bathgate, Ross A D; Hewitson, Tim D; Samuel, Chrishan S

    2014-07-01

    Fibrosis is a hallmark of chronic kidney disease, for which there is currently no effective cure. The hormone relaxin is emerging as an effective antifibrotic therapy; however, its mechanism of action is poorly understood. Recent studies have shown that relaxin disrupts the profibrotic actions of transforming growth factor-β1 (TGF-β1) by its cognate receptor, relaxin family peptide receptor 1 (RXFP1), extracellular signal-regulated kinase phosphorylation, and a neuronal nitric oxide synthase-dependent pathway to abrogate Smad2 phosphorylation. Since angiotensin II also inhibits TGF-β1 activity through its AT2 receptor (AT2R), we investigated the extent to which relaxin interacts with the AT2R. The effects of the AT2R antagonist, PD123319, on relaxin activity were examined in primary rat kidney myofibroblasts, and in kidney tissue from relaxin-treated male wild-type and AT2R-knockout mice subjected to unilateral ureteric obstruction. Relaxin's antifibrotic actions were significantly blocked by PD123319 in vitro and in vivo, or when relaxin was administered to AT2R-knockout mice. While heterodimer complexes were formed between RXFP1 and AT2Rs independent of ligand binding, relaxin did not directly bind to AT2Rs but signaled through RXFP1-AT2R heterodimers to induce its antifibrotic actions. These findings highlight a hitherto unrecognized interaction that may be targeted to control fibrosis progression. PMID:24429402

  18. G-Protein-Coupled Receptor MrgD Is a Receptor for Angiotensin-(1-7) Involving Adenylyl Cyclase, cAMP, and Phosphokinase A.

    Science.gov (United States)

    Tetzner, Anja; Gebolys, Kinga; Meinert, Christian; Klein, Sabine; Uhlich, Anja; Trebicka, Jonel; Villacañas, Óscar; Walther, Thomas

    2016-07-01

    Angiotensin (Ang)-(1-7) has cardiovascular protective effects and is the opponent of the often detrimental Ang II within the renin-angiotensin system. Although it is well accepted that the G-protein-coupled receptor Mas is a receptor for the heptapeptide, the lack in knowing initial signaling molecules stimulated by Ang-(1-7) prevented definitive characterization of ligand/receptor pharmacology as well as identification of further hypothesized receptors for the heptapeptide. The study aimed to identify a second messenger stimulated by Ang-(1-7) allowing confirmation as well as discovery of the heptapeptide's receptors. Ang-(1-7) elevates cAMP concentration in primary cells, such as endothelial or mesangial cells. Using cAMP as readout in receptor-transfected human embryonic kidney (HEK293) cells, we provided pharmacological proof that Mas is a functional receptor for Ang-(1-7). Moreover, we identified the G-protein-coupled receptor MrgD as a second receptor for Ang-(1-7). Consequently, the heptapeptide failed to increase cAMP concentration in primary mesangial cells with genetic deficiency in both Mas and MrgD Mice deficient in MrgD showed an impaired hemodynamic response after Ang-(1-7) administration. Furthermore, we excluded the Ang II type 2 receptor as a receptor for the heptapeptide but discovered that the Ang II type 2 blocker PD123319 can also block Mas and MrgD receptors. Our results lead to an expansion and partial revision of the renin-angiotensin system, by identifying a second receptor for Ang-(1-7), by excluding Ang II type 2 as a receptor for the heptapeptide, and by enforcing the revisit of such publications which concluded Ang II type 2 function by only using PD123319. PMID:27217404

  19. Increased natriuretic peptide receptor A and C gene expression in rats with pressure-overload cardiac hypertrophy

    DEFF Research Database (Denmark)

    Christoffersen, Tue E.H.; Aplin, Mark; Strom, Claes C.;

    2006-01-01

    Both atrial (ANP) and brain (BNP) natriuretic peptide affect development of cardiac hypertrophy and fibrosis via binding to natriuretic peptide receptor (NPR)-A in the heart. A putative clearance receptor, NPR-C, is believed to regulate cardiac levels of ANP and BNP. The renin-angiotensin system...... also affects cardiac hypertrophy and fibrosis. In this study we examined the expression of genes for the NPRs in rats with pressure-overload cardiac hypertrophy. The ANG II type 1 receptor was blocked with losartan (10 mg.kg(-1).day(-1)) to investigate a possible role of the renin-angiotensin system in...

  20. Long-term Angiotensin II AT1 receptor inhibition produces adipose tissue hypotrophy accompanied by increased expression of adiponectin and PPARγ.

    OpenAIRE

    Zorad, Stefan; Jing-tao DOU; Benicky, Julius; Hutanu, Daniel; Tybitanclova, Katarina; Zhou, Jin; Saavedra, Juan M

    2006-01-01

    To clarify the mechanism of the effects of angiotensin II AT1 receptor antagonists on adipose tissue, we treated 8 week-old male Wistar Kyoto rats with the angiotensin II AT1 receptor antagonist Candesartan cilexetil (10 mg/kg/day) for 18 weeks. Candesartan cilexetil reduced body weight gain, decreased fat tissue mass due to hypotrophy of epididymal and retroperitoneal adipose tissue and decreased adipocyte size without changing the number of adipocytes. Candesartan cilexetil decreased serum ...

  1. Long-term use of angiotensin receptor blockers and the risk of cancer.

    Directory of Open Access Journals (Sweden)

    Laurent Azoulay

    Full Text Available The association between angiotensin receptor blockers (ARBs and cancer is controversial with meta-analyses of randomized controlled trials and observational studies reporting conflicting results. Thus, the objective of this study was to determine whether ARBs are associated with an overall increased risk of the four most common cancers, namely, lung, colorectal, breast and prostate cancers, and to explore these effects separately for each cancer type. We conducted a retrospective cohort study using a nested case-control analysis within the United Kingdom (UK General Practice Research Database. We assembled a cohort of patients prescribed antihypertensive agents between 1995, the year the first ARB (losartan entered the UK market, and 2008, with follow-up until December 31, 2010. Cases were patients newly-diagnosed with lung, colorectal, breast and prostate cancer during follow-up. We used conditional logistic regression to estimate adjusted rate ratios (RRs and 95% confidence intervals (CIs of cancer incidence, comparing ever use of ARBs with ever use of diuretics and/or beta-blockers. The cohort included 1,165,781 patients, during which 41,059 patients were diagnosed with one of the cancers under study (rate 554/100,000 person-years. When compared to diuretics and/or beta-blockers, ever use of ARBs was not associated with an increased rate of cancer overall (RR: 1.00; 95% CI: 0.96-1.03 or with each cancer site separately. The use of angiotensin-converting enzyme inhibitors and calcium channel blockers was associated with an increased rate of lung cancer (RR: 1.13; 95% CI: 1.06-1.20 and RR: 1.19; 95% CI: 1.12-1.27, respectively. This study provides additional evidence that the use of ARBs does not increase the risk of cancer overall or any of the four major cancer sites. Additional research is needed to further investigate a potentially increased risk of lung cancer with angiotensin-converting enzyme inhibitors and calcium channel blockers.

  2. Mechanical stress triggers cardiomyocyte autophagy through angiotensin II type 1 receptor-mediated p38MAP kinase independently of angiotensin II.

    Directory of Open Access Journals (Sweden)

    Li Lin

    Full Text Available Angiotensin II (Ang II type 1 (AT1 receptor is known to mediate a variety of physiological actions of Ang II including autophagy. However, the role of AT1 receptor in cardiomyocyte autophagy triggered by mechanical stress still remains elusive. The aim of this study was therefore to examine whether and how AT1 receptor participates in cardiomyocyte autophagy induced by mechanical stresses. A 48-hour mechanical stretch and a 4-week transverse aorta constriction (TAC were imposed to cultured cardiomyocytes of neonatal rats and adult male C57B/L6 mice, respectively, to induce cardiomyocyte hypertrophy prior to the assessment of cardiomyocyte autophagy using LC3b-II. Losartan, an AT1 receptor blocker, but not PD123319, the AT2 inhibitor, was found to significantly reduce mechanical stretch-induced LC3b-II upregulation. Moreover, inhibition of p38MAP kinase attenuated not only mechanical stretch-induced cardiomyocyte hypertrophy but also autophagy. To the contrary, inhibition of ERK and JNK suppressed cardiac hypertrophy but not autophagy. Intriguingly, mechanical stretch-induced autophagy was significantly inhibited by Losartan in the absence of Ang II. Taken together, our results indicate that mechanical stress triggers cardiomyocyte autophagy through AT1 receptor-mediated activation of p38MAP kinase independently of Ang II.

  3. Angiotensin II type 2 receptor signaling significantly attenuates growth of murine pancreatic carcinoma grafts in syngeneic mice

    International Nuclear Information System (INIS)

    Pancreatic cancer is one of the most aggressive human malignancies, with a very poor prognosis. To evaluate the effect of angiotensin II (Ang II) type 2 receptor (AT2) expression in the host's body on the growth of pancreatic carcinoma, we have investigated the growth of mouse pancreatic ductal carcinoma grafts in syngeneic wild type and AT2 receptor-deficient (AT2-KO) mice. The role of AT2 receptor-signaling in stromal cells on the growth of murine pancreatic carcinoma cells (PAN02) was studied using various in vitro and in vivo assays. In vivo cell proliferation, apoptosis, and vasculature in tumors were monitored by Ki-67 immunostaining, TUNEL assay, and von Willebrand factor immunostaining, respectively. In the co-culture study, cell proliferation was measured by MTT cell viability assay. All the data were analyzed using t-test and data were treated as significant when p < 0.05. Our results show that the growth of subcutaneously transplanted syngeneic xenografts of PAN02 cells, mouse pancreatic ductal carcinoma cells derived from the C57/BL6 strain, was significantly faster in AT2-KO mice compared to control wild type mice. Immunohistochemical analysis of tumor tissue revealed significantly more Ki-67 positive cells in xenografts grown in AT2-KO mice than in wild type mice. The index of apoptosis is slightly higher in wild type mice than in AT2-KO mice as evaluated by TUNEL assay. Tumor vasculature number was significantly higher in AT2-KO mice than in wild type mice. In vitro co-culture studies revealed that the growth of PAN02 cells was significantly decreased when grown with AT2 receptor gene transfected wild type and AT2-KO mouse-derived fibroblasts. Faster tumor growth in AT2-KO mice may be associated with higher VEGF production in stromal cells. These results suggest that Ang II regulates the growth of pancreatic carcinoma cells through modulating functions of host stromal cells; Moreover, Ang II AT2 receptor signaling is a negative regulator in the

  4. Human fetal malformations associated with the use of an angiotensin II receptor antagonist: Case Report

    Directory of Open Access Journals (Sweden)

    Henri Augusto Korkes

    2014-09-01

    Full Text Available Introduction: The potential risks related to drug exposure during pregnancy represent a vast chapter in modern obstetrics and data regarding the safety of antihypertensive drugs during pregnancy are relatively scarce. Case report: A 37-year-old patient discovered her fifth pregnancy at our hospital after 26 weeks and 4 days of gestation. She reported a history of hypertension and was currently being treated with Losartan. Hospitalization was recommended for the patient and further evaluation of fetal vitality was performed. On the fourth day an ultrasound was performed, resulting in a severe oligohydramnios, fetal centralization and abnormal ductus venosus. After 36 hours, the newborn died. Pathologic evaluation: At autopsy, the skullcap had large fontanels and deficient ossification. The kidneys were slightly enlarged. A microscopic examination detected underdevelopment of the tubules and the presence of some dilated lumens. Immunohistochemical detection of epithelial membrane antigen was positive. Immunoreactivity of CD 15 was also assayed to characterize the proximal tubules, and lumen collapse was observed in some regions. Discussion: Angiotensin-converting enzyme inhibitors (ACEIs and angiotensin receptor antagonists (ARAs are among the most widely prescribed drugs for hypertension. They are often used by hypertensive women who are considering become pregnant. While their fetal toxicity in the second or third trimesters has been documented, their teratogenic effect during the first trimester has only recently been demonstrated. Conclusion: Constant awareness by physicians and patients should be encouraged, particularly in regard to the prescription of antihypertensive drugs in women of childbearing age who are or intend to become pregnant.

  5. Conditional expression of the type 2 angiotensin II receptor in mesenchymal stem cells inhibits neointimal formation after arterial injury.

    Science.gov (United States)

    Feng, Jian; Liu, Jian-Ping; Miao, Li; He, Guo-Xiang; Li, De; Wang, Hai-Dong; Jing, Tao

    2014-10-01

    Percutaneous coronary interventions (PCIs) are an effective treatment for obstructive coronary artery diseases. However, the procedure's success is limited by remodeling and formation of neointima. In the present study, we engineered rat mesenchymal stem cells (MSCs) to express type 2 angiotensin II receptor (AT2R) using a tetracycline-regulated system that can strictly regulate AT2R expression. We tested the ability of the modified MSCs to reduce neointima formation following arterial injury. We subjected rats to balloon injury, and reverse transcriptase polymerase chain reaction (RT-PCR) indicated no significant AT2R expression in normal rat arteries. Low expression of AT2R was observed at 28 days after balloon-induced injury. Interestingly, MSCs alone were unable to reduce neointimal hyperplasia after balloon-induced injury; after transplantation of modified MSCs, doxycycline treatment significantly upregulated neointimal AT2R expression and inhibited osteopontin mRNA expression, as well as neointimal formation. Taken together, these results suggest that transplantation of MSCs conditionally expressing AT2R could effectively suppress neointimal hyperplasia following balloon-induced injury. Therefore, MSCs with a doxycycline-controlled gene induction system may be useful for the management of arterial injury after PCI. PMID:25119854

  6. Angiotensin-(1-7 attenuates disuse skeletal muscle atrophy in mice via its receptor, Mas

    Directory of Open Access Journals (Sweden)

    María Gabriela Morales

    2016-04-01

    Full Text Available Immobilization is a form of disuse characterized by a loss of strength and muscle mass. Among the main features are decreased IGF-1/Akt signalling and increased ubiquitin-proteasome pathway signalling, which induce greater myosin heavy chain degradation. Activation of the classical renin-angiotensin system (RAS causes deleterious effects in skeletal muscle, including muscle wasting. In contrast, angiotensin-(1-7 [Ang-(1-7], a peptide of the non-classical RAS, produces beneficial effects in skeletal muscle. However, the role of Ang-(1-7 in skeletal muscle disuse atrophy and independent of classical RAS activation has not been evaluated. Therefore, we assessed the functions of Ang-(1-7 and the Mas receptor in disuse muscle atrophy in vivo using unilateral cast immobilization of the hind limb in male, 12-week-old wild-type (WT and Mas-knockout (Mas KO mice for 1 and 14 days. Additionally, we evaluated the participation of IGF-1/IGFR-1/Akt signalling and ubiquitin-proteasome pathway expression on the effects of Ang-(1-7 immobilization-induced muscle atrophy. Our results found that Ang-(1-7 prevented decreased muscle strength and reduced myofiber diameter, myosin heavy chain levels, and the induction of atrogin-1 and MuRF-1 expressions, all of which normally occur during immobilization. Analyses indicated that Ang-(1-7 increases IGF-1/IGFR-1/Akt pathway signalling through IGFR-1 and Akt phosphorylation, and the concomitant activation of two downstream targets of Akt, p70S6K and FoxO3. These anti-atrophic effects of Ang-(1-7 were not observed in Mas KO mice, indicating crucial participation of the Mas receptor. This report is the first to propose anti-atrophic effects of Ang-(1-7 via the Mas receptor and the participation of the IGF-1/IGFR-1/Akt/p70S6K/FoxO3 mechanism in disuse skeletal muscle atrophy.

  7. Aldosterone-Induced Vascular Remodeling and Endothelial Dysfunction Require Functional Angiotensin Type 1a Receptors.

    Science.gov (United States)

    Briet, Marie; Barhoumi, Tlili; Mian, Muhammad Oneeb Rehman; Coelho, Suellen C; Ouerd, Sofiane; Rautureau, Yohann; Coffman, Thomas M; Paradis, Pierre; Schiffrin, Ernesto L

    2016-05-01

    We investigated the role of angiotensin type 1a receptors (AGTR1a) in vascular injury induced by aldosterone activation of mineralocorticoid receptors inAgtr1a(-/-)and wild-type (WT) mice infused with aldosterone for 14 days while receiving 1% NaCl in drinking water. Aldosterone increased systolic blood pressure (BP) by ≈30 mm Hg in WT mice and ≈50 mm Hg inAgtr1a(-/-)mice. Aldosterone induced aortic and small artery remodeling, impaired endothelium-dependent relaxation in WT mice, and enhanced fibronectin and collagen deposition and vascular inflammation. None of these vascular effects were observed inAgtr1a(-/-)mice. Aldosterone effects were prevented by the AGTR1 antagonist losartan in WT mice. In contrast to aldosterone, norepinephrine caused similar BP increase and mesenteric artery remodeling in WT andAgtr1a(-/-)mice.Agtr1a(-/-)mice infused with aldosterone did not increase sodium excretion in response to a sodium chloride challenge, suggesting that sodium retention could contribute to the exaggerated BP rise induced by aldosterone.Agtr1a(-/-)mice had decreased mesenteric artery expression of the calcium-activated potassium channelKcnmb1, which may enhance myogenic tone and together with sodium retention, exacerbate BP responses to aldosterone/salt inAgtr1a(-/-)mice. We conclude that although aldosterone activation of mineralocorticoid receptors raises BP more inAgtr1a(-/-)mice, AGTR1a is required for mineralocorticoid receptor stimulation to induce vascular remodeling and inflammation and endothelial dysfunction. PMID:27045029

  8. Changes in angiotensin II receptor bindings in the hen neurohypophysis before and after oviposition.

    Science.gov (United States)

    Takahashi, T; Nozaki, Y; Nakagawa-Mizuyachi, K; Nakayama, H; Kawashima, M

    2011-11-01

    The present study was performed to elucidate whether the angiotensin II (ANG II) receptor exists in the plasma membrane fraction of the neurohypophysis in hens, to estimate the time of action of ANG II on the neurohypophysis before and after oviposition, and to examine relationships between the action of ANG II on the neurohypophysis and those of estrogen and prostaglandin F(2α) (PGF(2α)) in relation to arginine vasotocin (AVT) release. The specific binding had a binding specificity to chicken ANG II (cANG II), reversibility, and saturation in the [(125)I]cANG II binding assay. Scatchard analysis revealed that the binding sites are of a single class. The equilibrium dissociation constant (K(d)) obtained by kinetic analysis and Scatchard analysis suggested a high affinity, and the maximum binding capacity (B(max)) obtained by Scatchard analysis suggested a limited capacity. These results suggest that an ANG II receptor exists in the neurohypophysis of hens. The K(d) and the B(max) value was significantly smaller in laying hens than in nonlaying hens, which suggests that bindings of the cANG II receptor change, depending on the difference in laying condition. Values of the K(d) and the B(max) decreased approximately 15 min before oviposition in laying hens, and decreased 1 h after an intramuscular injection of estradiol-17β and 5 min after an intravenous injection of cANG II in nonlaying hens. The amount of specific binding of PGF(2α) receptor in the neurohypophysis also decreased and AVT concentration in blood increased after the cANG II injection. It seems likely that the action of cANG II in the neurohypophysis increases due to the effect of estrogen approximately 15 min before oviposition, and the cANG II action stimulates AVT release through the increase in the PGF(2α) action in this tissue. PMID:22010242

  9. Predicting kinase activity in angiotensin receptor phosphoproteomes based on sequence-motifs and interactions.

    Directory of Open Access Journals (Sweden)

    Rikke Bøgebo

    Full Text Available Recent progress in the understanding of seven-transmembrane receptor (7TMR signalling has promoted the development of a new generation of pathway selective ligands. The angiotensin II type I receptor (AT1aR is one of the most studied 7TMRs with respect to selective activation of the β-arrestin dependent signalling. Two complimentary global phosphoproteomics studies have analyzed the complex signalling induced by the AT1aR. Here we integrate the data sets from these studies and perform a joint analysis using a novel method for prediction of differential kinase activity from phosphoproteomics data. The method builds upon NetworKIN, which applies sophisticated linear motif analysis in combination with contextual network modelling to predict kinase-substrate associations with high accuracy and sensitivity. These predictions form the basis for subsequently nonparametric statistical analysis to identify likely activated kinases. This suggested that AT1aR-dependent signalling activates 48 of the 285 kinases detected in HEK293 cells. Of these, Aurora B, CLK3 and PKG1 have not previously been described in the pathway whereas others, such as PKA, PKB and PKC, are well known. In summary, we have developed a new method for kinase-centric analysis of phosphoproteomes to pinpoint differential kinase activity in large-scale data sets.

  10. Use of beta-blockers, angiotensin-converting enzyme inhibitors and angiotensin receptor blockers and breast cancer survival: Systematic review and meta-analysis.

    Science.gov (United States)

    Raimondi, Sara; Botteri, Edoardo; Munzone, Elisabetta; Cipolla, Carlo; Rotmensz, Nicole; DeCensi, Andrea; Gandini, Sara

    2016-07-01

    Breast cancer (BC) is the second leading cause of cancer death among women in Western Countries. Beta-blocker (BB) drugs, angiotensin-converting enzyme inhibitors (ACEi) and angiotensin receptor blockers (ARB) were suggested to have a favorable role in the development and progression of BC. We have performed a meta-analysis to clarify the potential benefits of these drugs on BC survival. A total number of 46 265 BC patients from eleven papers were included, ten independent studies on BB use and seven on ACEi/ARB use. The summary hazard ratio (SHR) was estimated by pooling the study-specific estimates with random effects models and maximum likelihood estimation. We assessed the homogeneity of the effects across studies and evaluated between-study heterogeneity by meta-regression and sensitivity analyses. We found a significant improvement in BC specific survival for patients treated with BB drugs at the time of BC diagnosis (SHR: 0.44; 95%CI: 0.26-0.73 with I(2)  = 78%). We also observed a borderline significant improvement in disease free survival for subjects treated with BB (SHR: 0.71, 95%CI: 0.19-1.03). No association of ACEi/ARB use with disease free and overall survival was found. In conclusion, we report epidemiological evidence that BB improve BC-specific survival. Clinical trials addressing this hypothesis are warranted. PMID:26916107

  11. Initial reduction of oxidative stress by angiotensin receptor blocker contributes long term outcomes after percutaneous coronary intervention

    OpenAIRE

    Noro, Tadanori; Takehara, Naofumi; Sumitomo, Kazuhiro; Takeuchi, Toshiharu; Ishii, Yoshinao; Kato, Jun-ichi; Kawabe, Jun-ichi; Hasebe, Naoyuki

    2014-01-01

    Background: It remains unclear whether administration of ARB with reactive oxygen species (ROS) scavenging effects improves the prognosis of patients undergoing PCI. Objectives: This study investigated whether the pre-intervention antioxidant effect of angiotensin receptor blocker (ARB) affects long-term outcomes in patients after successful percutaneous coronary intervention (PCI) without early adverse events. Methods: Fifty-two patients who underwent elective PCI were randomly assigned for ...

  12. Preventive Effects of the Angiotensin-II Receptor Blocker on Atrial Remodeling in an Ischemic Heart Failure Model of Rats

    OpenAIRE

    Yoon, Namsik; Kim, Kye Hun; Park, Keun Ho; Sim, Doo Sun; Youn, Hyun Ju; Hong, Young Joon; Park, Hyung Wook; Kim, Ju Han; Ahn, Youngkeun; Jeong, Myung Ho; Cho, Jeong Gwan; Park, Jong Chun

    2013-01-01

    Background and Objectives It is widely known that angiotensin-II receptor blockers (ARBs) have reverse remodeling effects in atrium. Although atrial fibrillation is frequent in ischemic heart failure clinically, experiments to demonstrate ARB's effects on atrial remodeling in a heart failure model are rare. Materials and Methods A heart failure model and a sham-operated group were formed in 25 Sprague-Dawley male rats of roughly 260 g in weight. Ischemic heart failure models were obtained via...

  13. The Effect of an Angiotensin Receptor Blocker on Arterial Stiffness in Type 2 Diabetes Mellitus Patients with Hypertension

    OpenAIRE

    Ji Hyun Kim; Su Jin Oh; Jung Min Lee; Eun Gyoung Hong; Jae Myung Yu; Kyung Ah Han; Kyung Wan Min; Hyun Shik Son; Sang Ah Chang

    2011-01-01

    Background Hypertension and type 2 diabetes mellitus are major risk factors for cardiovascular disease. This study analyzed the changes in central aortic waveforms and pulse wave velocity as well as related parameters after treatment with valsartan, an angiotensin II type 1 receptor blocker, in patients with type 2 diabetes and hypertension. Methods We used pulse wave analysis to measure central aortic waveform in a total of 98 subjects. In 47 of these patients, pulse wave velocity measuremen...

  14. Combined therapeutic benefit of mitochondria-targeted antioxidant, MitoQ10, and angiotensin receptor blocker, losartan, on cardiovascular function

    OpenAIRE

    McLachlan, Jennifer; Beattie, Elisabeth; Murphy, Michael P; Koh-Tan, Caline H.H.; Olson, Erin; Beattie, Wendy; Dominiczak, Anna F.; Nicklin, Stuart A.; Graham, Delyth

    2014-01-01

    Objective: Mitochondria-derived reactive oxygen species (ROS) play important roles in the development of cardiovascular disease highlighting the need for novel targeted therapies. This study assessed the potential therapeutic benefit of combining the mitochondria-specific antioxidant, MitoQ10, with the low-dose angiotensin receptor blocker (ARB), losartan, on attenuation of hypertension and left ventricular hypertrophy. In parallel, we investigated the impact of MitoQ10 on cardiac hypertro...

  15. Evolution of the nuclear receptor gene superfamily.

    OpenAIRE

    Laudet, V; Hänni, C; Coll, J.; F. Catzeflis; Stéhelin, D

    1992-01-01

    Nuclear receptor genes represent a large family of genes encoding receptors for various hydrophobic ligands such as steroids, vitamin D, retinoic acid and thyroid hormones. This family also contains genes encoding putative receptors for unknown ligands. Nuclear receptor gene products are composed of several domains important for transcriptional activation, DNA binding (C domain), hormone binding and dimerization (E domain). It is not known whether these genes have evolved through gene duplica...

  16. Mineralocorticoid and angiotensin II type 1 receptors in the subfornical organ mediate angiotensin II - induced hypothalamic reactive oxygen species and hypertension.

    Science.gov (United States)

    Wang, Hong-Wei; Huang, Bing S; White, Roselyn A; Chen, Aidong; Ahmad, Monir; Leenen, Frans H H

    2016-08-01

    Activation of angiotensinergic pathways by central aldosterone (Aldo)-mineralocorticoid receptor (MR) pathway plays a critical role in angiotensin II (Ang II)-induced hypertension. The subfornical organ (SFO) contains both MR and angiotensin II type 1 receptors (AT1R) and can relay the signals of circulating Ang II to downstream nuclei such as the paraventricular nucleus (PVN), supraoptic nucleus (SON) and rostral ventrolateral medulla (RVLM). In Wistar rats, subcutaneous (sc) infusion of Ang II at 500ng/min/kg for 1 or 2weeks increased reactive oxygen species (ROS) as measured by dihydroethidium (DHE) staining in a nucleus - specific pattern. Intra-SFO infusion of AAV-MR- or AT1aR-siRNA prevented the Ang II-induced increase in AT1R mRNA expression in the SFO and decreased MR mRNA. Both MR- and AT1aR-siRNA prevented increases in ROS in the PVN and RVLM. MR- but not AT1aR-siRNA in the SFO prevented the Ang II-induced ROS in the SON. Both MR- and AT1aR-siRNA in the SFO prevented most of the Ang II-induced hypertension as assessed by telemetry. These results indicate that Aldo-MR signaling in the SFO is needed for the activation of Ang II-AT1R-ROS signaling from the SFO to the PVN and RVLM. Activation of Aldo-MR signaling from the SFO to the SON may enhance AT1R dependent activation of pre-sympathetic neurons in the PVN. PMID:27163380

  17. Angiopoietin-like protein 2 expression is suppressed by angiotensin II via the angiotensin II type 1 receptor in rat cardiomyocytes.

    Science.gov (United States)

    Wang, Shuya; Li, Ying; Miao, Wei; Zhao, Hong; Zhang, Feng; Liu, Nan; Su, Guohai; Cai, Xiaojun

    2016-09-01

    The present study aimed to determine the inhibitory effects of angiotensin II (AngII) on angiopoietin‑like protein 2 (Angptl2) in rat primary cardiomyocytes, and to investigate the potential association between angiotensin II type 1 receptor (AT1R) and these effects. Cardiomyocytes were isolated from 3-day-old Wistar rats, and were cultured and identified. Subsequently, the expression levels of Angptl2 were detected following incubation with various concentrations of AngII for various durations using western blotting, reverse transcription‑quantitative polymerase chain reaction, enzyme-linked immunosorbent assay and immunofluorescence. Finally, under the most appropriate conditions (100 nmol/l AngII, 24 h), the cardiomyocytes were divided into six groups: Normal, AngII, AngII + losartan, normal + losartan, AngII + PD123319 and normal + PD123319 groups, in order to investigate the possible function of AT1R in Angptl2 suppression. Losartan and PD123319 are antagonists of AT1R and angiotensin II type 2 receptor, respectively. The statistical significance of the results was analyzed using Student's t‑test or one‑way analysis of variance. The results demonstrated that Angptl2 expression was evidently suppressed (P<0.05) following incubation with 100 nmol/l AngII for 24 h. Conversely, the expression levels of Angptl2 were significantly increased in the AngII + losartan group compared with the AngII group (P<0.01). However, no significant difference was detected between the AngII + PD123319, normal + losartan or normal + PD123319 groups and the normal group. The present in vitro study indicated that AngII was able to suppress Angptl2 expression, whereas losartan was able to significantly reverse this decrease by inhibiting AT1R. PMID:27483989

  18. 汉族人群中血管紧张素转换酶抑制剂所致咳嗽与血管紧张素转换酶基因及缓激肽β2受体基因多态性的关系%The Association between ACE Inhibitor (ACEI)-Induced Cough and the Polymorphism of Angiotensin Converting Enzyme (ACE) Gene and Bradykinin β2 Receptor(BDKRB2) Gene in Han Nationality

    Institute of Scientific and Technical Information of China (English)

    王刚; 杨军; 唐振旺; 宁国庆; 曹燕; 万娟

    2012-01-01

    Objective: To investigate the association between angiotensin converting enzyme inhibitor (ACEI)-induced cough and the polymorphism of angiotensin converting enzyme (ACE) gene and bradykinin ($2 receptor (BDKRB2) gene in Han nationality. Methods: Polymerase chain reaction (PCR) was used to examine ACE I/D and BDKRB2 CT polymorphism in 151 ACEI-induced cough subjects and 151 no cough subjects in Han population. And UV-method was used to detect the ACE activity. Results:ACE gene distribution in the cough group: type II was 47.0%, ID genotype was 42.4%, DD genotype was 10.6%; Non-cough group were 39.7%, 47.0%, 13.3% respectively, and there was statistically significant difference between the two groups(P 0.05); The level of ACE activity in the Cough group [(28.3 ± 10.1) U / L,] was significantly lower than non-cough group [(40.2 ± 9.4) U / L,(P <0.01).]. Conclusions: For han population, ACEI-induced cough related to ACE gene polymorphism and serum ACE activity, and there was no statistically significant association between BDKRB2 C / T and cough.%目的:探讨汉族人群中血管紧张素转换酶抑制剂(ACEI)所致咳嗽与血管紧张素转换酶(ACE)基因及缓激肽β2受体(BDKRB2)基因多态性的关系.方法:应用聚合酶链反应(PCR)方法,检测汉族人群中151例由于服用ACEI引起的咳嗽患者及151例未发生咳嗽的患者的ACEI/D及BDKRB2C/T的多态性,并采用紫外法检测ACE活性.结果:发现ACE基因分布在咳嗽组中Ⅱ型为47.0%,ID型为42.4%,DD型为10.6%;无咳嗽组分别为39.7%、47.0%、13.3%,两组相比其差异具有统计学意义(P<0.01);BDKRB2基因分布在咳嗽组中CC型为21.3%,CT型为50.0%,TT型为28.7%,无咳嗽组分别为22.5%、47.7%、29.8%,两组相比其差异无统计学意义(P>0.05);咳嗽组ACE活性水平为[(28.3±10.1)U/L]明显低于无咳嗽组[(40.2± 9.4)U/L],两组相比其差异具有统计学意义(P<0.01).结论:汉族人群中ACEI所致咳嗽

  19. The Functional Angiotensin Converting Enzyme Gene I/D Polymorphism Does not Alter Susceptibility to Chronic Pancreatitis

    Directory of Open Access Journals (Sweden)

    Whitcomb DC

    2004-11-01

    Full Text Available CONTEXT: Alterations of the renin-angiotensin system have been implicated in the pathogenesis of various diseases. The angiotensin converting enzyme is a key enzyme in the renin-angiotensin system. A deletion polymorphism of a 287-bp fragment of intron 16 of the angiotensin converting enzyme gene allele results in higher levels of circulating enzyme. ACE deletion genotype has been linked to heart diseases, sarcoidosis and liver fibrosis. The pancreatic renin-angiotensin system plays a role in the development of pancreatic fibrosis and ACE inhibitors decrease pancreatic fibrosis in experimental models. OBJECTIVES: We investigated the frequency of the ACE gene insertion/deletion polymorphism in chronic pancreatitis patients and controls. PATIENTS: Subjects with familial pancreatitis (n=51, sporadic chronic pancreatitis (n=104, and healthy controls (n=163 were evaluated. MAIN OUTCOME MEASURE: The presence of ACE insertion/deletion polymorphism. RESULTS: The frequency of the ACE gene deletion allele was similar in familial pancreatitis (49.0% sporadic pancreatitis (51.0% and controls (55.8%. Furthermore, there was no significant difference in clinical features between patients with ACE-insertion or insertion/deletion genotypes vs. patients with ACE-deletion genotype. CONCLUSION: We conclude that the ACE deletion genotype does not make a significant contribution to the pathogenesis and the progression of chronic pancreatitis.

  20. Biased Signaling of the Angiotensin II Type 1 Receptor Can Be Mediated through Distinct Mechanisms

    Science.gov (United States)

    Bonde, Marie Mi; Hansen, Jonas Tind; Sanni, Samra Joke; Haunsø, Stig; Gammeltoft, Steen; Lyngsø, Christina; Hansen, Jakob Lerche

    2010-01-01

    Background Seven transmembrane receptors (7TMRs) can adopt different active conformations facilitating a selective activation of either G protein or β-arrestin-dependent signaling pathways. This represents an opportunity for development of novel therapeutics targeting selective biological effects of a given receptor. Several studies on pathway separation have been performed, many of these on the Angiotensin II type 1 receptor (AT1R). It has been shown that certain ligands or mutations facilitate internalization and/or recruitment of β-arrestins without activation of G proteins. However, the underlying molecular mechanisms remain largely unresolved. For instance, it is unclear whether such selective G protein-uncoupling is caused by a lack of ability to interact with G proteins or rather by an increased ability of the receptor to recruit β-arrestins. Since uncoupling of G proteins by increased ability to recruit β-arrestins could lead to different cellular or in vivo outcomes than lack of ability to interact with G proteins, it is essential to distinguish between these two mechanisms. Methodology/Principal Findings We studied five AT1R mutants previously published to display pathway separation: D74N, DRY/AAY, Y292F, N298A, and Y302F (Ballesteros-Weinstein numbering: 2.50, 3.49–3.51, 7.43, 7.49, and 7.53). We find that D74N, DRY/AAY, and N298A mutants are more prone to β-arrestin recruitment than WT. In contrast, receptor mutants Y292F and Y302F showed impaired ability to recruit β-arrestin in response to Sar1-Ile4-Ile8 (SII) Ang II, a ligand solely activating the β-arrestin pathway. Conclusions/Significance Our analysis reveals that the underlying conformations induced by these AT1R mutants most likely represent principally different mechanisms of uncoupling the G protein, which for some mutants may be due to their increased ability to recruit β-arrestin2. Hereby, these findings have important implications for drug discovery and 7TMR biology and illustrate

  1. G protein-independent effects of the Angiotensin II type I receptor

    DEFF Research Database (Denmark)

    Christensen, Gitte Lund

    2010-01-01

    involveret i regulering af genekspression. Alligevel observerer vi at SII Ang II markant potentierer Isoproterenol og den β-adrenerge receptors evne til at inducere transkription, hvilket kan tyde på at G protein uafhængig signalering har en modulatorisk rolle i regulering af genekspression. Studierne der......Angiotensin II type 1 receptoren (AT1R) er en syv transmembranreceptor (7TMR) og et vigtigt terapeutisk target indenfor kardiovaskulær medicin. AT1R er gennem de seneste år blevet en model for det concept, at 7TMRer kan signalere via andre og mindre velbeskrevne signalveje end de G protein...... afhængige. Skæve agonister, som blokerer G protein signaleringen mens de samtidig aktiverer de G protein uafhængige signaleringsveje er blevet brugt til at beskrive de to hovedgrene i AT1R signaleringen i cellemodelsystemer. Vi påviser at denne farmakologiske differentiering af de to signalveje er relevant...

  2. Role of mineralocorticoid receptor and renin-angiotensin-aldosterone system in adipocyte dysfunction and obesity.

    Science.gov (United States)

    Feraco, Alessandra; Armani, Andrea; Mammi, Caterina; Fabbri, Andrea; Rosano, Giuseppe M C; Caprio, Massimiliano

    2013-09-01

    The mineralocorticoid receptor (MR) classically mediates aldosterone effects on salt homeostasis and blood pressure regulation in epithelial target tissues. In recent years, functional MRs have been identified in non classical targets of aldosterone actions, in particular in adipose tissue, where they mediate the effects of aldosterone and glucocorticoids in the control of adipogenesis, adipose expansion and its pro-inflammatory capacity. In this context, inappropriate MR activation has been demonstrated to be a causal factor in several pathologic conditions such as vascular inflammation, endothelial dysfunction, insulin resistance and obesity. The aim of this review is to summarize the latest developments in this rapidly developing field, and will focus on the role of MR and renin-angiotensin-aldosterone system (RAAS) as potential leading characters in the early steps of adipocyte dysfunction and obesity. Indeed modulation of MR activity in adipose tissue has promise as a novel therapeutic approach to treat obesity and its related metabolic complications. This article is part of a Special Issue entitled 'CSR 2013'. PMID:23454117

  3. Angiotensin II type 1 and 2 receptors and lymphatic vessels modulate lung remodeling and fibrosis in systemic sclerosis and idiopathic pulmonary fibrosis

    Directory of Open Access Journals (Sweden)

    Edwin Roger Parra

    2014-01-01

    Full Text Available OBJECTIVE: To validate the importance of the angiotensin II receptor isotypes and the lymphatic vessels in systemic sclerosis and idiopathic pulmonary fibrosis. METHODS: We examined angiotensin II type 1 and 2 receptors and lymphatic vessels in the pulmonary tissues obtained from open lung biopsies of 30 patients with systemic sclerosis and 28 patients with idiopathic pulmonary fibrosis. Their histologic patterns included cellular and fibrotic non-specific interstitial pneumonia for systemic sclerosis and usual interstitial pneumonia for idiopathic pulmonary fibrosis. We used immunohistochemistry and histomorphometry to evaluate the number of cells in the alveolar septae and the vessels stained by these markers. Survival curves were also used. RESULTS: We found a significantly increased percentage of septal and vessel cells immunostained for the angiotensin type 1 and 2 receptors in the systemic sclerosis and idiopathic pulmonary fibrosis patients compared with the controls. A similar percentage of angiotensin 2 receptor positive vessel cells was observed in fibrotic non-specific interstitial pneumonia and usual interstitial pneumonia. A significantly increased percentage of lymphatic vessels was present in the usual interstitial pneumonia group compared with the non-specific interstitial pneumonia and control groups. A Cox regression analysis showed a high risk of death for the patients with usual interstitial pneumonia and a high percentage of vessel cells immunostained for the angiotensin 2 receptor in the lymphatic vessels. CONCLUSION: We concluded that angiotensin II receptor expression in the lung parenchyma can potentially control organ remodeling and fibrosis, which suggests that strategies aimed at preventing high angiotensin 2 receptor expression may be used as potential therapeutic target in patients with pulmonary systemic sclerosis and idiopathic pulmonary fibrosis.

  4. Long-term angiotensin II AT1 receptor inhibition produces adipose tissue hypotrophy accompanied by increased expression of adiponectin and PPARgamma.

    Science.gov (United States)

    Zorad, Stefan; Dou, Jing-tao; Benicky, Julius; Hutanu, Daniel; Tybitanclova, Katarina; Zhou, Jin; Saavedra, Juan M

    2006-12-15

    To clarify the mechanism of the effects of angiotensin II AT(1) receptor antagonists on adipose tissue, we treated 8 week-old male Wistar Kyoto rats with the angiotensin II AT(1) receptor antagonist Candesartan cilexetil (10 mg/kg/day) for 18 weeks. Candesartan cilexetil reduced body weight gain, decreased fat tissue mass due to hypotrophy of epididymal and retroperitoneal adipose tissue and decreased adipocyte size without changing the number of adipocytes. Candesartan cilexetil decreased serum leptin levels and epididymal leptin mRNA, increased serum adiponectin levels and epididymal adiponectin mRNA, decreased epididymal tumor necrosis factor alpha (TNFalpha) mRNA, and increased fatty acid synthase mRNA. Considered free of peroxisome proliferator-activated receptor gamma (PPARgamma) agonist activity, Candesartan cilexetil increased epididymal expression of PPARgamma mRNA. The effects of Candesartan cilexetil on adipokine production and release may be attributable to PPARgamma activation and/or decrease in adipocyte cell size. In addition, Candesartan cilexetil treatment increased the expression of epididymal angiotensin II AT(2) receptor mRNA and protein and decreased the expression of renin receptor mRNA. These results suggest that Candesartan cilexetil influences lipid metabolism in adipose tissue by promoting adipose tissue rearrangement and modulating adipokine expression and release. These effects are probably consequences of local angiotensin II AT(1) receptor inhibition, angiotensin II AT(2) receptor stimulation, and perhaps additional angiotensin II-independent mechanisms. Our results indicate that the activity of local renin-angiotensin system plays an important role in adipose tissue metabolism. The decrease in the pro-inflammatory cytokine TNFalpha and the increase in the anti-inflammatory adipokine adiponectin indicate that Candesartan cilexetil may exert significant anti-inflammatory properties. PMID:17064684

  5. The effects of angiotensin II receptor antagonist (candesartan on rat renal vascular resistance

    Directory of Open Access Journals (Sweden)

    Supatraviwat, J

    2004-05-01

    Full Text Available The present study aimed to investigate the action of angiotensin II (AII on renal perfusion pressure and renal vascular resistance using noncompetitive AT1-receptor antagonist (candesartan or CV 11974. Experiments were performed in isolated kidney of adult male Wistar rats. Kreb's Henseleit solution was perfused into the renal artery at the rate of 3.5 ml/min. This flow rate was designed in order to maintain renal perfusion pressure between 80-120 mm Hg. Dose-response relationship between perfusion flow rate and AII concentration were studied. Renal perfusion pressure in response to 1, 10 and 100 nM AII were increased from basal perfusion pressure of 94±8 mm Hg to 127±6, 157±12 and 190±16 mm Hg, respectively. Administration of perfusate containing 11.4 μM candesartan for 30 min had no effect on the basal perfusion pressure. However, this significantly reduced renal perfusion pressure in the presence of AII (1, 10 and 100 nM by 39%, 47% and 61%, (n=7, P<0.05 respectively. At the basal perfusion pressure, calculated renal vascular resistance was 27±2 mm Hg · min · ml-1. However, the vascular resistance were found to be 41±1, 45±2 and 47±2 mm Hg · min · ml-1 when 1, 10 and 100 nM AII were added. Moreover, this dose of candesartan also showed a significant decrease in renal vascular resistance at the corresponding doses of AII by 38%, 48% and 43%, (n=7, P<0.05 respectively. The higher dose of candesartan (22.7 μM completely inhibited the action of 1, 10 and 100 nM AII on renal vasoconstriction. These results may indicate that the action of AII on renal vascular resistance is via AT1-receptor, at least in rat isolated perfusion kidney.

  6. Angiotensin AT2 receptor agonist prevents salt-sensitive hypertension in obese Zucker rats.

    Science.gov (United States)

    Ali, Quaisar; Patel, Sanket; Hussain, Tahir

    2015-06-15

    High-sodium intake is a risk factor for the pathogenesis of hypertension, especially in obesity. The present study is designed to investigate whether angiotensin type 2 receptor (AT2R) activation with selective agonist C21 prevents high-sodium diet (HSD)-induced hypertension in obese animals. Male obese rats were treated with AT2R agonist C21 (1 mg·kg(-1)·day(-1), oral) while maintained on either normal-sodium diet (NSD; 0.4%) or HSD (4%) for 2 wk. Radiotelemetric recording showed a time-dependent increase in systolic blood pressure in HSD-fed obese rats, being maximal increase (∼27 mmHg) at day 12 of the HSD regimen. C21 treatment completely prevented the increase in blood pressure of HSD-fed rats. Compared with NSD controls, HSD-fed obese rats had greater natriuresis/diuresis and urinary levels of nitrates, and these parameters were further increased by C21 treatment. Also, C21 treatment improved glomerular filtration rate in HSD-fed rats. HSD-fed rats expressed higher level of cortical ANG II, which was reduced to 50% by C21 treatment. HSD feeding and/or C21 treatment had no effects on cortical renin activity and the expression of angiotensin-converting enzyme (ACE) and chymase, which are ANG II-producing enzymes. However, ANG(1-7) concentration and ACE2 activity in the renal cortex were reduced by HSD feeding, and C21 treatment rescued both the parameters. Also, C21 treatment reduced the cortical expression of AT1R in HSD-fed rats, but had no effect of AT2R expression. We conclude that chronic treatment with the AT2R agonist C21 prevents salt-sensitive hypertension in obese rats, and a reduction in the renal ANG II/AT1R and enhanced ACE2/ANG(1-7) levels may play a potential role in this phenomenon. PMID:25855512

  7. Nitric oxide impacts on angiotensin AT2 receptor modulation of high-pressure baroreflex control of renal sympathetic nerve activity in anaesthetized rats

    OpenAIRE

    Abdulla, M H; Johns, E. J.

    2013-01-01

    Aim Nitric oxide (NO) interacts with the local brain renin-angiotensin system to modulate sympathetic outflow and cardiovascular homoeostasis. This study investigated whether NO influenced the ability of angiotensin AT2 receptor activation to modify the high-pressure baroreceptor regulation of renal sympathetic nerve activity (RSNA) and heart rate (HR). Methods Anaesthetized (chloralose/urethane) rats were prepared to allow generation of baroreflex gain curves for RSNA or HR following intrace...

  8. Angiotensin-converting enzyme gene I/D genotype affected metoprolol-induced reduction in 24-hour average heart rate

    Institute of Scientific and Technical Information of China (English)

    LIU Li-wei; LIU Hong; CHEN Guo-liang; HUANG Yi-ling; HAN Lu-lu; XU Zhi-min; JIANG Xiong-jing; LI Yi-shi

    2010-01-01

    Background Genetic factors can influence antihypertensive response to metoprolol, and many studies focused on the relationship between the genotype in β1-adrenergic receptor and blood pressure (BP), little was known about the association of angiotensin-converting enzyme (ACE) genotype with the therapeutic result of metoprolol. The present study aimed to investigate whether the ACE gene insertion (I) / deletion (D) polymorphism Is related to the response to metoprolol in Chinese Han hypertensive patients.Methods Ninety-six patients with essential hypertension received metoprolol (100 mg once daily) as monotherapy for 8 weeks. Twenty-four hours ambulatory blood pressure monitoring and dynamic electrocardiogram were performed before and after treatment. Genotyping analysis was performed using PCR. The association of the ACE gene I/D polymorphism with variations in BP and heart rate (HR) was observed after the 8-week treatment.Results The patients with ACE gene II polymorphism showed greater reduction in 24-hour average HR than those with ID or DD polymorphisms (P=0.045), no effect of this genotype on the reduction in seating HR or in BP was observed. After adjusting for age, gender, body mass index, BP and HR at baseline, the ACE gene I/D polymorphism was still an independent predictor for variations in 24-hour average HR.Conclusions The II polymorphism in ACE gene could be a candidate predictor for greater reduction in 24-hour average HR in Chinese Han hypertensive patients treated by metoprolol. Greater benefits would be obtained by patients with II polymorphism from the treatment with metoprolol. Larger studies are warranted to validate this finding.

  9. Structure and Function of Cross-class Complexes of G Protein-coupled Secretin and Angiotensin 1a Receptors.

    Science.gov (United States)

    Harikumar, Kaleeckal G; Augustine, Mary Lou; Lee, Leo T O; Chow, Billy K C; Miller, Laurence J

    2016-08-12

    Complexes of secretin (SecR) and angiotensin 1a (Atr1a) receptors have been proposed to be functionally important in osmoregulation, providing an explanation for overlapping and interdependent functions of hormones that bind and activate different classes of GPCRs. However, the nature of these cross-class complexes has not been well characterized and their signaling properties have not been systematically explored. We now use competitive inhibition of receptor bioluminescence resonance energy transfer and bimolecular fluorescence complementation to establish the dominant functionally important state as a symmetrical homodimeric form of SecR decorated by monomeric Atr1a, interacting through lipid-exposed faces of Atr1a TM1 and TM4. Conditions increasing prevalence of this complex exhibited negative allosteric modulatory impact on secretin-stimulated cAMP responses at SecR. In contrast, activating Atr1a with full agonist in such a complex exhibited a positive allosteric modulatory impact on the same signaling event. This modulation was functionally biased, with secretin-stimulated calcium responses unaffected, whereas angiotensin-stimulated calcium responses through the complex were reduced or absent. Further supporting this interpretation, Atr1a with mutations of lipid-exposed faces of TM1 and TM4 that did not affect its ability to bind or signal, could be expressed in the same cell as SecR, yet not exhibit either the negative or positive allosteric impact on cAMP observed with the inactive or activated states of wild type Atr1a on function, and not interfere with angiotensin-stimulated calcium responses like complexes with Atr1a. This may provide a more selective means of exploring the physiologic functional impact of this cross-class receptor complex without interfering with the function of either component receptor. PMID:27330080

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-06-11

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

  11. Role of angiotensin II and vasopressin receptors within the supraoptic nucleus in water and sodium intake induced by the injection of angiotensin II into the medial septal area

    Directory of Open Access Journals (Sweden)

    Antunes V.R.

    1998-01-01

    Full Text Available In this study we investigated the effects of the injection into the supraoptic nucleus (SON of non-peptide AT1- and AT2-angiotensin II (ANG II receptor antagonists, DuP753 and PD123319, as well as of the arginine-vasopressin (AVP receptor antagonist d(CH25-Tyr(Me-AVP, on water and 3% NaCl intake induced by the injection of ANG II into the medial septal area (MSA. The effects on water or 3% NaCl intake were assessed in 30-h water-deprived or in 20-h water-deprived furosemide-treated adult male rats, respectively. The drugs were injected in 0.5 ml over 30-60 s. Controls were injected with a similar volume of 0.15 M NaCl. Antagonists were injected at doses of 20, 80 and 180 nmol. Water and sodium intake was measured over a 2-h period. Previous administration of the AT1 receptor antagonist DuP753 into the SON decreased water (65%, N = 10, P<0.01 and sodium intake (81%, N = 8, P<0.01 induced by the injection of ANG II (10 nmol into the MSA. Neither of these responses was significantly changed by injection of the AT2-receptor antagonist PD123319 into the SON. On the other hand, while there was a decrease in water intake (45%, N = 9, P<0.01, ANG II-induced sodium intake was significantly increased (70%, N = 8, P<0.01 following injection of the V1-type vasopressin antagonist d(CH25-Tyr(Me-AVP into the SON. These results suggest that both AT1 and V1 receptors within the SON may be involved in water and sodium intake induced by the activation of ANG II receptors within the MSA. Furthermore, they do not support the involvement of MSA AT2 receptors in the mediation of these responses.

  12. Prognostic impact of carboxylesterase 1 gene variants in patients with congestive heart failure treated with angiotensin-converting enzyme inhibitors

    DEFF Research Database (Denmark)

    Nelveg-Kristensen, Karl E.; Madsen, Majbritt B.; Torp-Pedersen, Christian;

    2016-01-01

    OBJECTIVE: Most angiotensin-converting enzyme inhibitors (ACEIs) are prodrugs activated by carboxylesterase 1 (CES1). We investigated the prognostic importance of CES1 gene (CES1) copy number variation and the rs3815583 single-nucleotide polymorphism in CES1 among ACEI-treated patients with conge...

  13. Effect of angiotensin receptor blockade on endothelial function: focus on olmesartan medoxomil

    OpenAIRE

    Carlos Ferrario

    2009-01-01

    Carlos FerrarioHypertension and Vascular Disease Center, Wake Forest University School of Medicine, Winston-Salem, NC, USAAbstract: Endothelial dysfunction is the common link between cardiovascular disease risk factors and the earliest event in the cascade of incidents that results in target organ damage. Angiotensin II, the terminal pressor effector arm of the renin-angiotensin-aldosterone system, increases blood pressure (BP) by vasoconstriction and sodium and fluid retention, and has a pro...

  14. Combined effects of ramipril and angiotensinreceptor blocker TCV116 on rat congestive heart failure after myocardial infarction

    Institute of Scientific and Technical Information of China (English)

    TAO Ze-wei; HUANG Yuan-wei; XIA Qiang; XU Qi-wen

    2005-01-01

    Background Congestive heart failure (CHF) is a major cause of morbidity and mortality worldwide and angiotensin converting-enzyme inhibitor (ACEI) is the cornerstone in its treatment. However, CHF continues to progress despite this therapy, perhaps because of production of angiotensin Ⅱ (Ang Ⅱ) by alternative pathways. The present study was conducted to examine the combined effects of a chronic ACEI, ramipril, and a chronic Ang Ⅱ type 1 receptor blocker, TCV116, on rat CHF after myocardial infarction (MI). Methods Congestive heart failure was caused by MI in rats, which was induced by ligating the left anterior descending coronary artery. The experiment protocol included sham-operated rats (Sham), MI-control rats (MI-control), MI rats treated with ramipril 3 mg/kg (MI-ramipril) or TCV116 2 mg/kg (MI-TCV116) per day, half dosage (MI-1/2R&T) or full dosage (MI-R&T) combination of the two. At 22 weeks, cardiac hemodynamic parameters such as mean arterial pressure (MAP), left ventricular systolic pressure (LVSP), maximal rate of left ventricule pressure development and decline (LV dP/dtmax) and left ventricular end diastolic pressure (LVEDP), and cardiac morphometric parameters such as heart weight (HW), left ventricular weight (LVW) and left ventricular cavity area (LVCA) were measured, mRNA expressions of cardiac molecule genes such as β myosin heavy chain (βMHC), B-type natriuretic peptide (BNP), transforming growth factor-β1 (TGF-β1), collagen I and Ⅲ were quantified with reverse transcription polymerase chain reaction (RT-PCR) in the surviving septum myocardium, and survival rates were calculated. Results There were no significant differences in MI sizes (%) among each MI related experimental groups (33±13, 34±14, 33±13, 35±13 and 33±14 for MI-control, MI-ramipril, MI-TCV116, MI-1/2R&T and MI-R&T, respectively, no statistical significance for all). Compared with sham-operated rats, MI rats without therapy showed significant increases in

  15. Angiotensin-receptor blockers as therapy for mildto- moderate hypertension-associated non-alcoholic steatohepatitis

    Institute of Scientific and Technical Information of China (English)

    Eugen Florin Georgescu; Reanina Ionescu; Mihaela Niculescu; Laurentiu Mogoanta; Liliana Vancica

    2009-01-01

    AIM: To evaluate insulin resistance, cytolysis and nonalcoholic steatohepatitis (NASH) score (NAS) using the Kleiner and Brunt criteria in 54 patients with NASH and mild-to-moderate hypertension, treated with telmisartan vs valsartan for 20 mo. METHODS: All patients met the NCEP-ATP Ⅲ criteria for metabolic syndrome. Histology confirmed steatohepatitis, defined as a NAS greater than five up to 3 wk prior inclusion, using the current criteria. Patients with viral hepatitis, chronic alcohol intake, drug abuse or other significant immune or metabolic hepatic pathology were excluded. Subjects were randomly as -signed either to the valsartan (V) group (standard dose 80 mg o.d., n = 26), or to the telmisartan (T) group (standard dose 20 mg o.d., n = 28). Treatment had to be taken daily at the same hour with no concomitant medication or alcohol consumption allowed. Neither the patient nor the medical staff was aware of treatment group allocation. Paired liver biopsies obtained at inclusion (visit 1) and end of treatment (EOT) were assessed by a single blinded pathologist, not aware of patient or treatment group. Blood pressure, BMI, ALT, AST, HOMA-IR, plasma triglycerides (TG) and total cholesterol (TC) were evaluated at inclusion and every 4 mo until EOT (visit 6). RESULTS: At EOT we noticed a significant decrease in ALT levels vs inclusion in all patients and this decrease did not differ significantly in group T vs group V. HOMA-IR significantly decreased at EOT vs inclusion in all patients but in group T, the mean HOMA-IR decrease per month was higher than in group V. NAS significantly diminished at EOT in all patients with a higher decrease in group T vs group V. CONCLUSION: Angiotensin receptor blockers seem to be efficient in hypertension-associated NASH. Telmisartan showed a higher efficacy regarding insulin resistance and histology, perhaps because of its specific PPAR-gamma ligand effect.

  16. Angiotensin II type-2 receptor stimulation induces neuronal VEGF synthesis after cerebral ischemia.

    Science.gov (United States)

    Mateos, Laura; Perez-Alvarez, Maria Jose; Wandosell, Francisco

    2016-07-01

    Intense efforts are being undertaken to understand the pathobiology of ischemia and to develop novel and effective treatments. Angiotensin II type 2 receptor (AT2R) is related with a beneficial role in neurodegenerative disorders, including ischemia. However, the underlying molecular mechanism remains elusive. In this study, we have established that AT2R stimulation by C21 compound, a specific AT2R agonist, caused a VEGF upregulation. Using mouse primary cortical neurons exposed to oxygen-glucose deprivation (OGD), we established that this effect was mediated by a mechanism dependent of mTORC1 signaling since mTOR inhibition abolished the C21-induced VEGF upregulation. Also, we have temporally characterized the changes on VEGF levels after ischemia induction in rats using two different approaches: transient and permanent middle cerebral artery occlusion (tMCAO and pMCAO). VEGF levels were permanently augmented after reperfusion (tMCAO) whereas lower levels of VEGF were found after pMCAO, remarkably at 21days. Therefore, C21 compound accelerated the recovery of the neurological status of pMCAO rats, reduced the ischemic damage area and abolished pMCAO-induced VEGF downregulation at 21days. This effect of C21 compound was mainly observed in neurons of the peri-infarct area. Our results suggest that a C21-induced VEGF upregulation may be crucial after an ischemic neuronal insult in both of our experimental approaches. This upregulation was mediated by a mechanism dependent of Akt/mTOR signaling pathway, since mTOR inhibition abolished the VEGF upregulation induced by C21. Considering that VEGF is involved in regenerative processes, we propose that AT2R activation could be used as a potential pharmacological strategy after ischemic stroke. PMID:27045356

  17. Evidence to Consider Angiotensin II Receptor Blockers for the Treatment of Early Alzheimer's Disease.

    Science.gov (United States)

    Saavedra, Juan M

    2016-03-01

    Alzheimer's disease is the most frequent type of dementia and diagnosed late in the progression of the illness when irreversible brain tissue loss has already occurred. For this reason, treatments have been ineffective. It is imperative to find novel therapies ameliorating modifiable risk factors (hypertension, stroke, diabetes, chronic kidney disease, and traumatic brain injury) and effective against early pathogenic mechanisms including alterations in cerebral blood flow leading to poor oxygenation and decreased access to nutrients, impaired glucose metabolism, chronic inflammation, and glutamate excitotoxicity. Angiotensin II receptor blockers (ARBs) fulfill these requirements. ARBs are directly neuroprotective against early injury factors in neuronal, astrocyte, microglia, and cerebrovascular endothelial cell cultures. ARBs protect cerebral blood flow and reduce injury to the blood brain barrier and neurological and cognitive loss in animal models of brain ischemia, traumatic brain injury, and Alzheimer's disease. These compounds are clinically effective against major risk factors for Alzheimer's disease: hypertension, stroke, chronic kidney disease, diabetes and metabolic syndrome, and ameliorate age-dependent cognitive loss. Controlled studies on hypertensive patients, open trials, case reports, and database meta-analysis indicate significant therapeutic effects of ARBs in Alzheimer's disease. ARBs are safe compounds, widely used to treat cardiovascular and metabolic disorders in humans, and although they reduce hypertension, they do not affect blood pressure in normotensive individuals. Overall, there is sufficient evidence to consider long-term controlled clinical studies with ARBs in patients suffering from established risk factors, in patients with early cognitive loss, or in normal individuals when reliable biomarkers of Alzheimer's disease risk are identified. PMID:26993513

  18. Angiotensin AT(2 receptor contributes towards gender bias in weight gain.

    Directory of Open Access Journals (Sweden)

    Preethi Samuel

    Full Text Available Obesity is a major disease condition, in turn leading to pathological changes collectively recognized as metabolic syndrome. Recently angiotensin receptor AT(2R has been associated negatively with body weight (BW gain in male mice. However, the gender differences in AT(2R and BW changes have not been studied. To understand the gender based role of AT(2R involving BW changes, we fed male and female wild type (WT and AT(2R knock out (AT(2KO mice with C57BL6 background with high fat diet (HFD for 16 weeks. The male AT(2KO had higher HFD calorie intake (WT: 1280±80; AT(2KO:1680±80 kcal but gained less BW compared with the WT (WT: 13; AT(2KO: 6 g. Contrary to the male animals, the female AT(2KO mice with equivalent caloric intake (WT: 1424±48; AT(2KO:1456±80 kcal gained significantly more BW than the WT mice (WT: 9 g; AT(2KO: 15 g. The male AT(2KO on HFD displayed lower plasma insulin level, less impaired glucose tolerance (GT, and higher plasma T3 compared with WT males on HFD; whereas the female AT(2KO mice on HFD showed elevated levels of plasma insulin, more impaired GT, lower plasma T3 and higher free fatty acid and hepatic triglycerides compared with WT females on HFD. Interestingly, compared with WT, AT(2KO female mice had significantly lower estrogen, which was further reduced by HFD. These results suggest that AT(2R in female mice via potentially regulating estrogen may have protective role against BW gain and impaired glucose tolerance and lipid metabolism.

  19. Angiotensin II receptor expression and relation to Helicobacter pylori-infection in the stomach of the Mongolian gerbil

    Directory of Open Access Journals (Sweden)

    Fändriks Lars

    2010-01-01

    Full Text Available Abstract Background The role of the renin-angiotensin system in gastric physiology and disease has as yet been sparsely explored. The first aim of the study was to investigate the baseline presence and location of angiotensin II receptors (AT1R and AT2R in the stomach of the Mongolian gerbil. A second aim was to elucidate whether the presence of H. pylori infection is associated with changes in the expression of these receptors. Methods H. pylori-negative and H. pylori-infected (strain SS1 or TN2GF4 male Mongolian gerbils were investigated. The stomachs were examined at six or 12 months after inoculation by the use of immunohistochemistry, western blot and microscopic morphometry. Results AT1R and AT2R were located in a variety of cells in the gerbil gastric wall, including a subpopulation of endocrine cells in the antral mucosa and inflammatory cells infiltrating H. pylori-infected stomachs. Gerbils infected with the SS1 strain showed a significantly increased antral AT1R protein expression and an increased number of infiltrating polymorphonuclear leucocytes (PMNs at 12 months. The AT1R protein expression correlated with the number of PMNs and the antral expression of myeloperoxidase. Conclusions Angiotensin II receptors are present in a variety of cells in the gastric wall of the Mongolian gerbil. The results indicate an influence dependent on the H. pylori strain on the gastric AT1R expression and a relationship between gastric AT1R expression and mucosal PMNs infiltration.

  20. Angiotensin Ⅱ type 2 receptor gene mediated by the tetracycline-regulatable system inhibits neointimal hyperplasia in rat carotid arteries after balloon angioplasty%血管紧张素Ⅱ2型受体在体可调控表达对大鼠颈动脉新生内膜增生的影响

    Institute of Scientific and Technical Information of China (English)

    苗莉; 罗先润; 景涛; 张辉; 刘安丰; 娄云霄; 何国祥

    2011-01-01

    Objective Transducing the angiotensin Ⅱ type 2 receptor (AT2R) gene into rat balloon injury carotid arteries can attenuate neointimal hyperplasia, but how to regulate the expression of the AT2.R gene according to our need is very important in utilizing transgenie technology. The purpose of the current study is to investigate the effects of the AT2R gene medicated by the tetracy-cline regulatable system on neointimal hyperplasia in rat carotid arteries after balloon angioplasty. Methods After establishment of the rat model of carotid balloon injury restenosis, we locally perfused into the rat carotid arteries PBS (the control group), mesenchy-mal stem cells (the MSC group) or MSC/AT2R (the MSC/AT2R group) with AT2R medicated by the tetracycline regulatable system, the latter again subdivided into a doxycycline administration (Dox) and non-doxycycline Dox administration (non-Dox) group. At 14 and 28 days after the operation, we evaluated the expression of AT2R by immunohistochemistry and RT-PCR and measured the neointi-ma/media (I/M) area ratio was by morphometric analysis. Results In the MSC/AT2R + Dox group, the expressions of AT2R mRNA and protein in the neointima were significantly up-regulated from day 14 to 28 after injury (P <0.01), and the I/M ratio significantly reduced (P<0.01). The transplanted MSC showed no obvious effect on the neointimal hyperplasia. Conclusion The expression of the AT2R gene can be regulated efficiently in vivo by local delivery of MSC with dual-stable expression of the AT2R gene, and thus inhibit neointimal hyperplasia.%目的 血管紧张素Ⅱ2型受体(angiotensinⅡtype 2 receptor,AT2R)基因转染可减轻血管损伤后新生内膜的过度增生,但如何主动调控转入体内基因的表达有着重要的临床意义.文中以四环素可调控系统下的AT2R基因转染的骨髓间充质干细胞(mesenchymal stem cell,MSC)为载体,探讨AT2R在体可调控表达及对大鼠颈动脉新生内膜的影响.方法 大鼠

  1. Angiotensin II receptor subtypes are coupled with distinct signal-transduction mechanisms in neurons and astrocytes from rat brain

    Energy Technology Data Exchange (ETDEWEB)

    Sumners, C.; Wei Tang; Zelezna, B.; Raizada, M.K. (Univ. of Florida, Gainesville (United States))

    1991-09-01

    Both neurons and astrocytes contain specific receptors for angiotensin II (AII). The authors used selective ligands for the AT{sub 1} and AT{sub 2} types of AII receptors to investigate the expression of functional receptor subtypes in astrocyte cultures and neuron cultures from 1-day-old (neonatal) rat brain. In astrocyte cultures, competition of {sup 125}I-labeled AII ({sup 125}I-AII) specific binding with AT{sub 1} (DuP753) or AT{sub 2} {l brace}PD123177, CGP42112A, (Phe(p-NH{sub 2}){sup 6})AII{r brace} selective receptor ligands revealed a potency series of AII > DuP753 > > > CGP42112A > (Phe(p-NH{sub 2}){sup 6})AII > PD123177. These results suggest a predominance of the AT{sub 1} receptor subtype in neonatal astrocytes. {sup 125}I-AII specific binding to neonate neuronal cultures was reduced 73-84% by 1 {mu} MPD123177, and the residual {sup 125}I-AII specific binding was eliminated by DuP753. The results suggest that astrocyte cultures from neonatal rat brains contain predominantly AT{sub 1} receptors that are coupled to a stimulation of inositophospholipid hydrolysis. In contrast, neuron cultures from neonatal rat brain contain mostly AT{sub 2} receptors that are coupled to a reduction in basal cGMP levels, but a smaller population of AT{sub 1} receptors is also present in these neurons.

  2. IMPACT OF ANGIOTENSIN-CONVERTING ENZYME GENE POLYMORPHISM ON THE DEVELOPMENT OF INSULIN RESISTANCE SYNDROME

    Directory of Open Access Journals (Sweden)

    G. E. Roitberg

    2013-01-01

    Full Text Available Objective: to analyze the distribution of components of insulin resistance (IR syndrome and to study the frequency of their combinations in relation to the genotypes and allelic variants of the angiotensin-converting enzyme (ACE gene.Subjects and methods. A group of clinically healthy patients (50 women and 42 men with different genotypes of the ACE gene was examined.The distribution of IR syndrome components and the frequency of their combinations were analyzed in relation to the genotypes and allelicvariants of the ACE gene.Results. A group of D allele carriers compared to A allele ones showed a pronounced tendency for the frequency of IR to reduce due to thehigher proportion of patients with complete IR syndrome. This observation becomes statistically significant in the assessment of homozygous variants of the ACE gene. At the same time dyslipidemia and hypertension in the presence of IR significantly more frequently occurred in patients with the DD genotype than in those with genotype II.Conclusion. There was a marked predominance of the manifestations of IR syndrome with a complete set of components in the DD genotypicgroup, which confirms the significant strong association between ACE gene polymorphism and IR syndrome.

  3. Dosage of angiotensin-II receptor blockers in heart failure patients following changes in Danish drug reimbursement policies

    DEFF Research Database (Denmark)

    Selmer, Christian; Lamberts, Morten; Kristensen, Søren Lund;

    2014-01-01

    PURPOSE: National reimbursement policies in Denmark were changed in November 2010 favouring a shift in angiotensin-II receptor blocker (ARB) treatment to generic losartan for heart failure (HF) patients. We examined how changes in reimbursement policies affected the fraction of HF patients up......, respectively. Individual-level linkage of nationwide registries of hospitalization and drug dispensing in Denmark was used to describe patterns of ARB prescriptions and estimate dosage before and after November 2010. Logistic regression models were used to assess the probability for being up-titrated in the...

  4. Vitamin D receptor activation and downregulation of renin-angiotensin system attenuate morphine-induced T cell apoptosis

    OpenAIRE

    Chandel, Nirupama; Sharma, Bipin; Salhan, Divya; Husain, Mohammad; Malhotra, Ashwani; Buch, Shilpa; Singhal, Pravin C.

    2012-01-01

    Opiates have been reported to induce T cell loss. We evaluated the role of vitamin D receptor (VDR) and the activation of the renin-angiotensin system (RAS) in morphine-induced T cell loss. Morphine-treated human T cells displayed downregulation of VDR and the activation of the RAS. On the other hand, a VDR agonist (EB1089) enhanced T cell VDR expression both under basal and morphine-stimulated states. Since T cells with silenced VDR displayed the activation of the RAS, whereas activation of ...

  5. Angiotensin II receptor blocker ameliorates stress-induced adipose tissue inflammation and insulin resistance.

    Directory of Open Access Journals (Sweden)

    Motoharu Hayashi

    Full Text Available A strong causal link exists between psychological stress and insulin resistance as well with hypertension. Meanwhile, stress-related responses play critical roles in glucose metabolism in hypertensive patients. As clinical trials suggest that angiotensin-receptor blocker delays the onset of diabetes in hypertensive patients, we investigated the effects of irbesartan on stress-induced adipose tissue inflammation and insulin resistance. C57BL/6J mice were subjected to 2-week intermittent restraint stress and orally treated with vehicle, 3 and 10 mg/kg/day irbesartan. The plasma concentrations of lipid and proinflammatory cytokines [Monocyte Chemoattractant Protein-1 (MCP-1, tumor necrosis factor-α, and interleukin-6] were assessed with enzyme-linked immunosorbent assay. Monocyte/macrophage accumulation in inguinal white adipose tissue (WAT was observed with CD11b-positive cell counts and mRNA expressions of CD68 and F4/80 using immunohistochemistry and RT-PCR methods respectively. The mRNA levels of angiotensinogen, proinflammatory cytokines shown above, and adiponectin in WAT were also assessed with RT-PCR method. Glucose metabolism was assessed by glucose tolerance tests (GTTs and insulin tolerance tests, and mRNA expression of insulin receptor substrate-1 (IRS-1 and glucose transporter 4 (GLUT4 in WAT. Restraint stress increased monocyte accumulation, plasma free fatty acids, expression of angiotensinogen and proinflammatory cytokines including MCP-1, and reduced adiponectin. Irbesartan reduced stress-induced monocyte accumulation in WAT in a dose dependent manner. Irbesartan treatment also suppressed induction of adipose angiotensinogen and proinflammatory cytokines in WAT and blood, and reversed changes in adiponectin expression. Notably, irbesartan suppressed stress-induced reduction in adipose tissue weight and free fatty acid release, and improved insulin tolerance with restoration of IRS-1 and GLUT4 mRNA expressions in WAT. The results

  6. The angiotensin-converting enzyme (ACE gene family of Anopheles gambiae

    Directory of Open Access Journals (Sweden)

    Isaac R Elwyn

    2005-12-01

    Full Text Available Abstract Background Members of the M2 family of peptidases, related to mammalian angiotensin converting enzyme (ACE, play important roles in regulating a number of physiological processes. As more invertebrate genomes are sequenced, there is increasing evidence of a variety of M2 peptidase genes, even within a single species. The function of these ACE-like proteins is largely unknown. Sequencing of the A. gambiae genome has revealed a number of ACE-like genes but probable errors in the Ensembl annotation have left the number of ACE-like genes, and their structure, unclear. Results TBLASTN and sequence analysis of cDNAs revealed that the A. gambiae genome contains nine genes (AnoACE genes which code for proteins with similarity to mammalian ACE. Eight of these genes code for putative single domain enzymes similar to other insect ACEs described so far. AnoACE9, however, has several features in common with mammalian somatic ACE such as a two domain structure and a hydrophobic C terminus. Four of the AnoACE genes (2, 3, 7 and 9 were shown to be expressed at a variety of developmental stages. Expression of AnoACE3, AnoACE7 and AnoACE9 is induced by a blood meal, with AnoACE7 showing the largest (approximately 10-fold induction. Conclusion Genes coding for two-domain ACEs have arisen several times during the course of evolution suggesting a common selective advantage to having an ACE with two active-sites in tandem in a single protein. AnoACE7 belongs to a sub-group of insect ACEs which are likely to be membrane-bound and which have an unusual, conserved gene structure.

  7. Angiotensin Type-2 Receptors Influence the Activity of Vasopressin Neurons in the Paraventricular Nucleus of the Hypothalamus in Male Mice.

    Science.gov (United States)

    de Kloet, Annette D; Pitra, Soledad; Wang, Lei; Hiller, Helmut; Pioquinto, David J; Smith, Justin A; Sumners, Colin; Stern, Javier E; Krause, Eric G

    2016-08-01

    It is known that angiotensin-II acts at its type-1 receptor to stimulate vasopressin (AVP) secretion, which may contribute to angiotensin-II-induced hypertension. Less well known is the impact of angiotensin type-2 receptor (AT2R) activation on these processes. Studies conducted in a transgenic AT2R enhanced green fluorescent protein reporter mouse revealed that although AT2R are not themselves localized to AVP neurons within the paraventricular nucleus of the hypothalamus (PVN), they are localized to neurons that extend processes into the PVN. In the present set of studies, we set out to characterize the origin, phenotype, and function of nerve terminals within the PVN that arise from AT2R-enhanced green fluorescent protein-positive neurons and synapse onto AVP neurons. Initial experiments combined genetic and neuroanatomical techniques to determine that γ-aminobutyric acid (GABA)ergic neurons derived from the peri-PVN area containing AT2R make appositions onto AVP neurons within the PVN, thereby positioning AT2R to negatively regulate neuroendocrine secretion. Subsequent patch-clamp electrophysiological experiments revealed that selective activation of AT2R in the peri-PVN area using compound 21 facilitates inhibitory (ie, GABAergic) neurotransmission and leads to reduced activity of AVP neurons within the PVN. Final experiments determined the functional impact of AT2R activation by testing the effects of compound 21 on plasma AVP levels. Collectively, these experiments revealed that AT2R expressing neurons make GABAergic synapses onto AVP neurons that inhibit AVP neuronal activity and suppress baseline systemic AVP levels. These findings have direct implications in the targeting of AT2R for disorders of AVP secretion and also for the alleviation of high blood pressure. PMID:27267713

  8. Disposition and metabolism of [(14)C] Sacubitril/Valsartan (formerly LCZ696) an angiotensin receptor neprilysin inhibitor, in healthy subjects.

    Science.gov (United States)

    Flarakos, Jimmy; Du, Yancy; Bedman, Timothy; Al-Share, Qusai; Jordaan, Pierre; Chandra, Priya; Albrecht, Diego; Wang, Lai; Gu, Helen; Einolf, Heidi J; Huskey, Su-Er; Mangold, James B

    2016-11-01

    1. Sacubitril/valsartan (LCZ696) is an angiotensin receptor neprilysin inhibitor (ARNI) providing simultaneous inhibition of neprilysin (neutral endopeptidase 24.11; NEP) and blockade of the angiotensin II type-1 (AT1) receptor. 2. Following oral administration, [(14)C]LCZ696 delivers systemic exposure to valsartan and AHU377 (sacubitril), which is rapidly metabolized to LBQ657 (M1), the biologically active neprilysin inhibitor. Peak sacubitril plasma concentrations were reached within 0.5-1 h. The mean terminal half-lives of sacubitril, LBQ657 and valsartan were ∼1.3, ∼12 and ∼21 h, respectively. 3. Renal excretion was the dominant route of elimination of radioactivity in human. Urine accounted for 51.7-67.8% and feces for 36.9 to 48.3 % of the total radioactivity. The majority of the drug was excreted as the active metabolite LBQ657 in urine and feces, total accounting for ∼85.5% of the total dose. 4. Based upon in vitro studies, the potential for LCZ696 to inhibit or induce cytochrome P450 (CYP) enzymes and cause CYP-mediated drug interactions clinically was found to be low. PMID:26931777

  9. RU28318, an Aldosterone Antagonist, in Combination with an ACE Inhibitor and Angiotensin Receptor Blocker Attenuates Cardiac Dysfunction in Diabetes

    Science.gov (United States)

    Benter, Ibrahim F.; Babiker, Fawzi; Al-Rashdan, Ibrahim; Yousif, Mariam; Akhtar, Saghir

    2013-01-01

    Aims. We evaluated the effects of RU28318 (RU), a selective mineralocorticoid receptor (MR) antagonist, Captopril (Capt), an angiotensin converting enzyme inhibitor, and Losartan (Los), an angiotensin receptor blocker, alone or in combination with ischemia/reperfusion- (I/R-) induced cardiac dysfunction in hearts obtained from normal and diabetic rats. Methods. Isolated hearts were perfused for 30 min and then subjected to 30 min of global ischemia (I) followed by a period of 30 min of reperfusion (R). Drugs were administered for 30 min either before or after ischemia. Drug regimens tested were RU, Capt, Los, RU + Capt, RU + Los, Capt + Los, and RU + Capt + Los (Triple). Recovery of cardiac hemodynamics was evaluated. Results. Recovery of cardiac function was up to 5-fold worse in hearts obtained from diabetic animals compared to controls. Treatment with RU was generally better in preventing or reversing ischemia-induced cardiac dysfunction in normal hearts compared to treatment with Capt or Los alone. In diabetic hearts, RU was generally similarly effective as Capt or Los treatment. Conclusions. RU treatment locally might be considered as an effective therapy or preventative measure in cardiac I/R injury. Importantly, RU was the most effective at improving −dP/dt (a measure of diastolic function) when administered to diabetic hearts after ischemia. PMID:24066305

  10. RU28318, an Aldosterone Antagonist, in Combination with an ACE Inhibitor and Angiotensin Receptor Blocker Attenuates Cardiac Dysfunction in Diabetes

    Directory of Open Access Journals (Sweden)

    Ibrahim F. Benter

    2013-01-01

    Full Text Available Aims. We evaluated the effects of RU28318 (RU, a selective mineralocorticoid receptor (MR antagonist, Captopril (Capt, an angiotensin converting enzyme inhibitor, and Losartan (Los, an angiotensin receptor blocker, alone or in combination with ischemia/reperfusion- (I/R- induced cardiac dysfunction in hearts obtained from normal and diabetic rats. Methods. Isolated hearts were perfused for 30 min and then subjected to 30 min of global ischemia (I followed by a period of 30 min of reperfusion (R. Drugs were administered for 30 min either before or after ischemia. Drug regimens tested were RU, Capt, Los, RU + Capt, RU + Los, Capt + Los, and RU + Capt + Los (Triple. Recovery of cardiac hemodynamics was evaluated. Results. Recovery of cardiac function was up to 5-fold worse in hearts obtained from diabetic animals compared to controls. Treatment with RU was generally better in preventing or reversing ischemia-induced cardiac dysfunction in normal hearts compared to treatment with Capt or Los alone. In diabetic hearts, RU was generally similarly effective as Capt or Los treatment. Conclusions. RU treatment locally might be considered as an effective therapy or preventative measure in cardiac I/R injury. Importantly, RU was the most effective at improving -dP/dt (a measure of diastolic function when administered to diabetic hearts after ischemia.

  11. Insertion/deletion polymorphism of the angiotensin-converting enzyme gene and the risk of hypertension among residents of two cities, South-South Nigeria

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    Mary Esien Kooffreh

    2014-01-01

    Conclusion: The I/D polymorphism of the angiotensin-converting enzyme gene was a risk factor for hypertension in the sample population of Calabar and Uyo. This research will form baseline information for subsequent molecular studies in this population.

  12. In vitro inhibition of [3H]-angiotensin II binding on the human AT1 receptor by proanthocyanidins from Guazuma ulmifolia bark.

    Science.gov (United States)

    Caballero-George, Catherina; Vanderheyden, Patrick M L; De Bruyne, Tess; Shahat, Abdel-Atty; Van den Heuvel, Hilde; Solis, Pablo N; Gupta, Mahabir P; Claeys, Magda; Pieters, Luc; Vauquelin, Georges; Vlietinck, Arnold J

    2002-12-01

    A bioassay-guided fractionation of the 70% acetone extract of the bark of Guazuma ulmifolia Lam. on the inhibition of angiotensin II binding to the AT 1 receptor led to the isolation and identification of bioactive oligomeric and polymeric proanthocyanidins consisting mainly of (-)-epicatechin units. The displacement of [3H]-angiotensin II binding was dose-dependent and correlated with the degree of polymerization of the different fractions containing proanthocyanidins. A strong displacement was seen for the residual fraction suggesting that the most active substances corresponding to the highly polymerized proanthocyanidins. Angiotensin II AT 1 receptor binding might be considered as a potentially interesting biological activity of proanthocyanidins contributing to the very broad spectrum of biological activities of the condensed tannins. PMID:12494331

  13. New Aspects of Ace Inhibition: Importance of ACE co-localization with angiotensin and bradykinin receptors

    NARCIS (Netherlands)

    B. Tom (Beril)

    2003-01-01

    textabstractThe beneficial effect of angiotensin-converting enzyme (ACE) inhibitors in hypertension and heart failure may relate, at least in part, to their capacity to interfere with bradykinin metabolism. In addition, recent studies have provided evidence for bradykinin-potentiating effects of ACE

  14. Carotid remodeling of hypertensive subjects and polymorphism of the angiotensin-converting enzyme gene

    Institute of Scientific and Technical Information of China (English)

    李世军; 孙宁玲; 周素敏

    2004-01-01

    Background This study was designed to investigate the relationships between changes in the structure and function of carotid arteries and angiotensin converting enzyme (ACE) gene polymorphism in Chinese hypertensive subjects. Methods Multiplex polymerase chain reaction amplification was used to evaluate the ACE gene insertion/deletion (I/D) polymorphism. High-resolution B-mode ultrasound examinations were performed to detect parameters of carotid artery remodeling. Results Intima-media thickness (IMT) was significantly different among the DD, ID and II genotypes of ACE (DD>ID>II, P0.05) in hypertensive subjects. The frequency of the DD gene and D allele of ACE were higher in patients with thickening carotid than in patients with normal carotid (70.4% vs 24.1%, and 79.5% vs 40.5%, respectively, P<0.001). In multiple stepwise regression analysis, independent risk factors for increased carotid IMT in hypertensive subjects were ACE genotypes (P<0.001), age (P<0.001) and carotid internal diameter (P=0.032). Moreover, triglycerides and total cholesterol were higher in patients with the DD genotype than in those with the II genotype (P<0.05). Conclusions The I/D polymorphism of the ACE gene was related to IMT, but not to internal diameter, distensibility and stiffness of the carotid in Chinese hypertensive subjects. ACE gene polymorphism was a main risk factor for increased carotid IMT. These results may imply that there is a link between lipid metabolism and ACE genotype polymorphism in Chinese hypertensive subjects.

  15. Polymorphisms of renin-angiotensin-aldosterone system gene in chinese han patients with nonfamilial atrial fibrillation.

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    Li-Qun Zhao

    Full Text Available Atrial fibrillation(AF is the most common arrhythmia in the adult population. The activated renin-angiotensin-aldosterone system (RAS has been reported to play an important role in the pathogenesis of atrial fibrillation. The aim of this study was to investigate the association between nonfamilial AF and polymorphisms in RAS gene.A total of 931 patients with nonfamilial AF, 663 non-AF heart disease patients and 727 healthy subjects were selected. 10 tagSNPs (tSNPs (ACE gene rs8066114, AGT gene rs7539020, rs3789678, rs2478544, rs11568023, rs2478523, rs4762, rs699 and CYP11B2 rs3802230, rs3097 were chosen and genotyped in our study. Single-locus analysis and haplotype analysis were used in this study.In single-locus analysis, we found rs11568023 and rs3789678 in AGT gene were associated with nonfamilial AF in Chinese Han population. AF risk was associated with rs3789678 between the AF group and control groups. Under dominant model, the significant AF risk was observed in rs3789678 between the AF group and non AF heart control group; And the protective effect was found in rs11568023, compared with the non-AF heart disease control group. In multilocus haplotype analysis, the association between frequencies of the haplotypes and AF risk was showed in AGT gene (rs7539020-rs3789678, compared 'TT' haplotype with the common 'TC' haplotype, adjusted for age, gender, LVEF, LVEDD, LAD and frequency of hypertension and diabetes. The diplotype with 'TC', carrying rs3789678-C-allele, was associated with reduced risk of AF between the AF group and the healthy control group. The diplotype with 'TT' haplotype in the same block, carrying rs3789678-T-allele, was associated with increased risk of AF.Via a large-scale case-control study, we found that rs3789678 site was potential susceptible locus of AF whereas rs11568023 was protective factor.

  16. Common angiotensin receptor blockers may directly modulate the immune system via VDR, PPAR and CCR2b

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    Lee Robert E

    2006-01-01

    Full Text Available Abstract Background There have been indications that common Angiotensin Receptor Blockers (ARBs may be exerting anti-inflammatory actions by directly modulating the immune system. We decided to use molecular modelling to rapidly assess which of the potential targets might justify the expense of detailed laboratory validation. We first studied the VDR nuclear receptor, which is activated by the secosteroid hormone 1,25-dihydroxyvitamin-D. This receptor mediates the expression of regulators as ubiquitous as GnRH (Gonadatrophin hormone releasing hormone and the Parathyroid Hormone (PTH. Additionally we examined Peroxisome Proliferator-Activated Receptor Gamma (PPARgamma, which affects the function of phagocytic cells, and the C-CChemokine Receptor, type 2b, (CCR2b, which recruits monocytes to the site of inflammatory immune challenge. Results Telmisartan was predicted to strongly antagonize (Ki≈0.04nmol the VDR. The ARBs Olmesartan, Irbesartan and Valsartan (Ki≈10 nmol are likely to be useful VDR antagonists at typical in-vivo concentrations. Candesartan (Ki≈30 nmol and Losartan (Ki≈70 nmol may also usefully inhibit the VDR. Telmisartan is a strong modulator of PPARgamma (Ki≈0.3 nmol, while Losartan (Ki≈3 nmol, Irbesartan (Ki≈6 nmol, Olmesartan and Valsartan (Ki≈12 nmol also seem likely to have significant PPAR modulatory activity. Olmesartan andIrbesartan (Ki≈9 nmol additionally act as antagonists of a theoretical modelof CCR2b. Initial validation of this CCR2b model was performed, and a proposed model for the AngiotensinII Type1 receptor (AT2R1 has been presented. Conclusion Molecular modeling has proven valuable to generate testable hypotheses concerning receptor/ligand binding and is an important tool in drug design. ARBs were designed to act as antagonists for AT2R1, and it was not surprising to discover their affinity for the structurally similar CCR2b. However, this study also found evidence that ARBs modulate the

  17. Renin-Angiotensin System Genes Polymorphisms and Essential Hypertension in Burkina Faso, West Africa

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    Daméhan Tchelougou

    2015-01-01

    Full Text Available Objective. This study aimed to investigate the association between three polymorphisms of renin-angiotensin system and the essential hypertension in the population of Burkina Faso. Methodology. This was a case-control study including 202 cases and 204 matched controls subjects. The polymorphisms were identified by a classical and a real-time PCR. Results. The AGT 235M/T and AT1R 1166A/C polymorphisms were not associated with the hypertension while the genotype frequencies of the ACE I/D polymorphism between patients and controls (DD: 66.83% and 35.78%, ID: 28.22% and 50.98%, II: 4.95% and 13.24%, resp. were significantly different (p < 10−4. The genotype DD of ACE gene (OR = 3.40, p < 0.0001, the increasing age (OR = 3.83, p < 0.0001, obesity (OR = 4.84, p < 0.0001, dyslipidemia (OR = 3.43, p = 0.021, and alcohol intake (OR = 2.76, p < 0.0001 were identified as the independent risk factors for hypertension by multinomial logistic regression. Conclusion. The DD genotype of the ACE gene is involved in susceptibility to hypertension. Further investigations are needed to better monitor and provide individualized care for hypertensive patients.

  18. Angiotensin Converting Enzyme Gene Polymorphism in Egyptian Patients with Systemic Lupus Erythematosus

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    El-Shafeey M.M., El-Shayeb M., Othman E. and Elfawy N

    2005-12-01

    Full Text Available Systemic lupus erythematosus (SLE shows various clinical manifestations with various immunological abnormalities. The development of lupus nephritis and vasculitis is common in patients with SLE. As angiotensin I-converting enzyme (ACE has been reported to be associated with various immunological phenomena, we investigated the correlation between insertion(I / deletion(D polymorphism of the ACE gene and SLE. Fifty Egyptian patients with SLE and thirty healthy control persons were involved in this study. ACE gene was detected by the polymerase chain reaction (PCR. In SLE patients, there is a significant difference when comparing DD and II genotypes (P<0.05,being higher in the DD genotype. And a highly significant difference when comparing ID and II genotypes (P=0.001, being much higher in ID genotype than II genotype. According to vasculitis, there is a significant relationship between vasculitis and patients genotypes when comparing ID genotype with both II and DD genotypes (P<0.05, being highest in ID genotype. There is a significant relationship found when comparing ID genotype with both II and DD genotypes, being highest in ID genotype in patients with score 21. These results suggest that the ACE genotype could be associated with SLE.

  19. The importance of short-term off-target effects in estimating the long-term renal and cardiovascular protection of angiotensin receptor blockers

    DEFF Research Database (Denmark)

    Smink, P A; Miao, Y; Eijkemans, M J C;

    2014-01-01

    Angiotensin receptor blockers (ARBs) have multiple effects that may contribute to their efficacy on renal/cardiovascular outcomes. We developed and validated a risk score that incorporated short-term changes in multiple risk markers to predict the ARB effect on renal/cardiovascular outcomes. The ...

  20. Angiotensin II type 1 receptor blocker telmisartan induces apoptosis and autophagy in adult T-cell leukemia cells.

    Science.gov (United States)

    Kozako, Tomohiro; Soeda, Shuhei; Yoshimitsu, Makoto; Arima, Naomichi; Kuroki, Ayako; Hirata, Shinya; Tanaka, Hiroaki; Imakyure, Osamu; Tone, Nanako; Honda, Shin-Ichiro; Soeda, Shinji

    2016-05-01

    Adult T-cell leukemia/lymphoma (ATL), an aggressive T-cell malignancy that develops after long-term infection with human T-cell leukemia virus (HTLV-1), requires new treatments. Drug repositioning, reuse of a drug previously approved for the treatment of another condition to treat ATL, offers the possibility of reduced time and risk. Among clinically available angiotensin II receptor blockers, telmisartan is well known for its unique ability to activate peroxisome proliferator-activated receptor-γ, which plays various roles in lipid metabolism, cellular differentiation, and apoptosis. Here, telmisartan reduced cell viability and enhanced apoptotic cells via caspase activation in ex vivo peripheral blood monocytes from asymptomatic HTLV-1 carriers (ACs) or via caspase-independent cell death in acute-type ATL, which has a poor prognosis. Telmisartan also induced significant growth inhibition and apoptosis in leukemia cell lines via caspase activation, whereas other angiotensin II receptor blockers did not induce cell death. Interestingly, telmisartan increased the LC3-II-enriched protein fraction, indicating autophagosome accumulation and autophagy. Thus, telmisartan simultaneously caused caspase activation and autophagy. A hypertension medication with antiproliferation effects on primary and leukemia cells is intriguing. Patients with an early diagnosis of ATL are generally monitored until the disease progresses; thus, suppression of progression from AC and indolent ATL to acute ATL is important. Our results suggest that telmisartan is highly effective against primary cells and leukemia cell lines in caspase-dependent and -independent manners, and its clinical use may suppress acute transformation and improve prognosis of patients with this mortal disease. This is the first report demonstrating a cell growth-inhibitory effect of telmisartan in fresh peripheral blood mononuclear cells from leukemia patients. PMID:27419050

  1. Role of Mas receptor in renal blood flow response to angiotensin-(1-7 in ovariectomized estradiol treated rats

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    Shadan Saberi

    2016-01-01

    Full Text Available The angiotensin 1-7 (Ang 1-7, is abundantly produced in kidneys and antagonizes the function of angiotensin II through Mas receptor (MasR or other unknown mechanisms. In the current study, the role of MasR and steroid hormone estrogen on renal blood flow response to Ang 1-7 administration was investigated in ovariectomized (OV female rats. OV female Wistar-rats received estradiol (500 μg/kg/week or vehicle for two weeks. In the day of the experiment, the animals were anesthetized, cannulated, and the responses including mean arterial pressure, renal blood flow (RBF, and renal vascular resistance at the constant level of renal perfusion pressure to graded infusion of Ang 1-7 at 0, 100 and 300 ng/kg/min were determined in OV and OV estradiol-treated (OVE rats, treated with vehicle or MasR antagonist; A779. RBF response to Ang 1-7 infusion increased dose-dependently in vehicle (P dose <0.001 and A779-treated (P dose<0.01 animals. However, when MasR was blocked, the RBF response to Ang 1-7 significantly increased in OV animals compared with OVE rats (P<0.05. When estradiol was limited by ovariectomy, A779 increased RBF response to Ang 1-7 administration, while this response was attenuated in OVE animals.

  2. Angiotensin II receptor blockers in the prevention of complications from atrial fibrillation

    OpenAIRE

    Eide, Stephanie

    2009-01-01

    Gerald V Naccarelli,1 Frank Peacock21Penn State Heart and Vascular institute, Hershey, Pennsylvania, USA; 2Cleveland Clinic, Cleveland, Ohio, USAAbstract: Atrial fibrillation (AF) is the most common form of cardiac arrhythmia and is associated with an increased risk of cardiovascular morbidity and mortality, especially due to ischemic stroke. The occurrence of AF leads to atrial electrical and structural remodeling. The renin-angiotensin system appears to play a role in the development of atr...

  3. Angiotensin II receptor blockers in the prevention of complications from atrial fibrillation

    OpenAIRE

    Gerald V. Naccarelli; Peacock, Frank

    2009-01-01

    Atrial fibrillation (AF) is the most common form of cardiac arrhythmia and is associated with an increased risk of cardiovascular morbidity and mortality, especially due to ischemic stroke. The occurrence of AF leads to atrial electrical and structural remodeling. The renin-angiotensin system appears to play a role in the development of atrial arrhythmias by its involvement in both of these processes. Large-scale hypertension trials and heart failure trials have indicated the potential value ...

  4. Increasing brain angiotensin converting enzyme 2 activity decreases anxiety-like behavior in male mice by activating central Mas receptors.

    Science.gov (United States)

    Wang, Lei; de Kloet, Annette D; Pati, Dipanwita; Hiller, Helmut; Smith, Justin A; Pioquinto, David J; Ludin, Jacob A; Oh, S Paul; Katovich, Michael J; Frazier, Charles J; Raizada, Mohan K; Krause, Eric G

    2016-06-01

    Over-activation of the brain renin-angiotensin system (RAS) has been implicated in the etiology of anxiety disorders. Angiotensin converting enzyme 2 (ACE2) inhibits RAS activity by converting angiotensin-II, the effector peptide of RAS, to angiotensin-(1-7), which activates the Mas receptor (MasR). Whether increasing brain ACE2 activity reduces anxiety by stimulating central MasR is unknown. To test the hypothesis that increasing brain ACE2 activity reduces anxiety-like behavior via central MasR stimulation, we generated male mice overexpressing ACE2 (ACE2 KI mice) and wild type littermate controls (WT). ACE2 KI mice explored the open arms of the elevated plus maze (EPM) significantly more than WT, suggesting increasing ACE2 activity is anxiolytic. Central delivery of diminazene aceturate, an ACE2 activator, to C57BL/6 mice also reduced anxiety-like behavior in the EPM, but centrally administering ACE2 KI mice A-779, a MasR antagonist, abolished their anxiolytic phenotype, suggesting that ACE2 reduces anxiety-like behavior by activating central MasR. To identify the brain circuits mediating these effects, we measured Fos, a marker of neuronal activation, subsequent to EPM exposure and found that ACE2 KI mice had decreased Fos in the bed nucleus of stria terminalis but had increased Fos in the basolateral amygdala (BLA). Within the BLA, we determined that ∼62% of GABAergic neurons contained MasR mRNA and expression of MasR mRNA was upregulated by ACE2 overexpression, suggesting that ACE2 may influence GABA neurotransmission within the BLA via MasR activation. Indeed, ACE2 overexpression was associated with increased frequency of spontaneous inhibitory postsynaptic currents (indicative of presynaptic release of GABA) onto BLA pyramidal neurons and central infusion of A-779 eliminated this effect. Collectively, these results suggest that ACE2 may reduce anxiety-like behavior by activating central MasR that facilitate GABA release onto pyramidal neurons within the

  5. ANGIOTENSIN I CONVERTING ENZYME GENE POLYMORPHISM AND EXERCISE TRAINABILITY IN ELDERLY WOMEN: AN ELECTROCARDIOLOGICAL APPROACH

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    Takuro Tobina

    2007-06-01

    Full Text Available Angiotensin I converting enzyme (ACE gene Insertion / Deletion (I/D polymorphism is associated with exercise trainability and exercise induced left ventricular hypertrophy. However, it is unclear whether this polymorphism influences exercise trainability in the elderly, and the electrocardiological alterations by exercise training is unknown among the genotypes. We herein investigated the association between ACE gene insertion/deletion (I/D polymorphism, exercise trainability and the electrocardiological alternations by exercise in elderly women. Eighty four elderly women participated in this study. In all subjects the leg extension power (LEP and lactate threshold (LT were determined in order to evaluate the muscle strength, aerobic capacity and to also select the appropriate training intensity for each individual. They performed bench step exercise training for 12 weeks. A resting electrocardiogram was recorded for the obtained QTc interval in before and after the program. The baseline of aerobic capacity was higher in I/I than that in I/D, and the QTc interval was shorter in I/I than that in I/D. All other characteristics were similar among the genotypes. The QTc interval tended to be shorten only in the D/D. Furthermore, the value of the QTc interval change showed a significant difference between the I/I and D/D genotype after the program. The LT and LEP demonstrated a similar response among the genotypes. The D allele of ACE gene I/D polymorphism may therefore play a role in the electrocardiological aspect during exercise training, however, it was not found to influence the aerobic capacity

  6. Association of polymorphisms in angiotensin-converting enzyme gene with gestational diabetes mellitus in Indian women

    Science.gov (United States)

    Aggarwal, Parul; Agarwal, Nutan; Das, Nibhriti; Dalal, Krishna

    2016-01-01

    Background: Numerous genes have been reported in relation with gestational diabetes mellitus (GDM), but the findings were not consistently replicated across populations, or there have been no detailed studies on them. Previous literatures suggested that, out of all angiotensin converting enzyme (ACE) gene polymorphisms, only ACE insertion/deletion (I/D) gene polymorphism has a strong association with GDM in Asian Indian women. Aim: This study was devoted to evaluate the association of four single nucleotide polymorphisms (SNPs) ACE A240T, C1237T, G2350A and I/D with GDM and Type 2 diabetes mellitus. Materials and Methods: This study recruited 105 GDM cases, 119 Type 2 diabetes mellitus subjects and 120 controls. PCR-RFLP was used for identifying genotypes of ACE A240T, C1237T and G2350A and PCR was performed in the case of ACE I/D. Results: Significant associations of ACE SNP's, C1237T, and G2350A with GDM were observed. Haplotype analysis revealed the remarkably significant evidence of association with SNP combination ACE A240T, C1237T, G2350A, and I/D with GDM patients (P = 0.024). Individuals possessing haplotype “TTAI” (frequency 30% in GDM and 0 in controls) derived from these SNPs had 185 fold increased risk of developing GDM (95% of confidence interval: 11.13–3102.15), which was highest when compared with other 15 haplotypes. Conclusion: Shorter-range haplotypes were also significant, but the only consistently associated alleles were found to be in ACE C1237T, G2350A, and I/D. These results suggested that the variant in close proximity to ACE C1237T, G2350A and/or I/D modulates susceptibility to GDM and noninsulin dependent diabetes mellitus in Indian women. PMID:26958520

  7. DNA methylation analysis of the angiotensin converting enzyme (ACE gene in major depression.

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    Peter Zill

    Full Text Available BACKGROUND: The angiotensin converting enzyme (ACE has been repeatedly discussed as susceptibility factor for major depression (MD and the bi-directional relation between MD and cardiovascular disorders (CVD. In this context, functional polymorphisms of the ACE gene have been linked to depression, to antidepressant treatment response, to ACE serum concentrations, as well as to hypertension, myocardial infarction and CVD risk markers. The mostly investigated ACE Ins/Del polymorphism accounts for ~40%-50% of the ACE serum concentration variance, the remaining half is probably determined by other genetic, environmental or epigenetic factors, but these are poorly understood. MATERIALS AND METHODS: The main aim of the present study was the analysis of the DNA methylation pattern in the regulatory region of the ACE gene in peripheral leukocytes of 81 MD patients and 81 healthy controls. RESULTS: We detected intensive DNA methylation within a recently described, functional important region of the ACE gene promoter including hypermethylation in depressed patients (p = 0.008 and a significant inverse correlation between the ACE serum concentration and ACE promoter methylation frequency in the total sample (p = 0.02. Furthermore, a significant inverse correlation between the concentrations of the inflammatory CVD risk markers ICAM-1, E-selectin and P-selectin and the degree of ACE promoter methylation in MD patients could be demonstrated (p = 0.01 - 0.04. CONCLUSION: The results of the present study suggest that aberrations in ACE promoter DNA methylation may be an underlying cause of MD and probably a common pathogenic factor for the bi-directional relationship between MD and cardiovascular disorders.

  8. Angiotensin-converting enzyme gene (ACE) insertion/deletion polymorphism in Mexican populations.

    Science.gov (United States)

    Vargas-Alarcón, Gilberto; Hernández-Pacheco, Guadalupe; Rodríguez-Pérez, José Manuel; Pérez-Hernández, Nonanzit; Pavón, Zinnia; Fragoso, José Manuel; Juarez-Cedillo, Teresa; Villarreal-Garza, Cynthia; Granados, Julio

    2003-12-01

    The angiotensin-converting enzyme gene (ACE) insertion/deletion polymorphism was determined in 211 Mexican healthy individuals belonging to different Mexican ethnic groups (98 Mestizos, 64 Teenek, and 49 Nahuas). ACE polymorphism differed among Mexicans with a high frequency of the D allele and the D/D genotype in Mexican Mestizos. The D/D genotype was absent in Teenek and present in only one Nahua individual (2.0%). When comparisons were made, we observed that Caucasian, African, and Asian populations presented the highest frequencies of the D allele, whereas Amerindian (Teenek and Pima) and Australian Aboriginals showed the highest frequencies of the I allele. The distribution of I/D genotype was heterogeneous in all populations: Australian Aboriginals presented the lowest frequency (4.9%), whereas Nahuas presented the highest (73.4%). The present study shows the frequencies of a polymorphism not analyzed previously in Mexican populations and establishes that this polymorphism distinguishes the Amerindian populations of other groups. On the other hand, since ACE alleles have been associated with genetic susceptibility to developing cardiovascular diseases and hypertension, knowledge of the distribution of these alleles could help to define the true significance of ACE polymorphism as a genetic susceptibility marker in the Amerindian populations. PMID:15018037

  9. Simultaneous determination of multiple angiotensin type 1 receptor antagonists and its application to high-throughput pharmacokinetic study

    Science.gov (United States)

    Zhu, Xiaoyan; Sun, Jianguo; Hao, Haiping; Wang, Guangji; Hu, Xiaoling; Lv, Hua; Gu, Shenghua; Wu, Xiaoming; Xu, Jinyi

    2008-05-01

    A rapid and sensitive high performance liquid chromatography-electrospray tandem mass spectrometry (HPLC-ESI-MS/MS) detection was developed for the simultaneous determination of multiple angiotensin type 1 receptor antagonists (AT1RAs) WX472, WX581, 1b and telmisartan in rat plasma for the purpose of high-throughout pharmacokinetic screening. The method was operated under selected reaction monitoring (SRM) mode in the positive ion mode. The analytes and the internal standard (pitavastatin) were extracted from 100 [mu]L rat plasma under acidic conditions by liquid-liquid extraction with ethyl acetate. The analytes and internal standard were baseline separated on a Gemini analytical column (3 [mu]m, 150 mm × 2.0 mm) with the adoption of a gradient elution using acetonitrile and 0.05% aqueous formic acid. The standard curves were linear in the concentration ranges of 4.5-900 ng/mL for WX472, 5-1000 ng/mL for WX581 and 0.5-100 ng/mL for 1b and telmisartan. Intra- and inter-batch precisions (R.S.D.%) were all within 15% and the method assessed a quite good accuracy (R.E.%). Recoveries were found to be >65% for all the compounds and no obvious matrix effects were found. This method has been successfully applied to the high-throughput pharmacokinetic screening study for both cassette dosing and cassette analysis of four compounds to rats. Significant drug-drug interactions were observed after cassette dosing. The study suggested that cassette analysis of pooled samples would be a better choice for the high-throughput pharmacokinetic screening of angiotensin type 1 receptor antagonists.

  10. G16R single nucleotide polymorphism but not haplotypes of the ß2-adrenergic receptor gene alters cardiac output in humans

    DEFF Research Database (Denmark)

    Rokamp, Kim Z; Staalsø, Jonatan M; Gartmann, Martin;

    2013-01-01

    Variation in genes encoding the ß2-adrenergic receptor (ADRB2) and angiotensin-converting enzyme (ACE) may influence Q¿ (cardiac output). The 46G>A (G16R) SNP (single nucleotide polymorphism) has been associated with ß2-mediated vasodilation, but the effect of ADRB2 haplotypes on Q¿ has not been ...

  11. A RETROSPECTIVE STUDY ON THE POTENTIAL DRUG INTERACTION BETWEEN ANGIOTENSIN CONVERTING ENZYME INHIBITOR OR ANGIOTENSIN RECEPTOR ANTAGONIST AND OTHER DRUGS IN END-STAGE CHRONIC RENAL FAILURE PATIENTS

    Directory of Open Access Journals (Sweden)

    Honey Iskandar

    2012-10-01

    Full Text Available Increasing number of chronic renal failure (CRF patients had reflected an increase in the number of patients with diabetes and hypertension. Therefore, health practitioners would be faced with management of complicated medical problems for the patients of chronic renal disease. In this way, various complications of chronic renal failure would lead to polypharmacy, where the patients receive three to five drugs in a dose. Development of polypharmacy had made the potential of drug interaction greater. The objective was to determine whether CRF patients admitted to hospital with specific adverse drug reactions were likely to have been prescribed with interacting drugs. Retrospective study was designed. The study was conducted at the General Practice Rooms Floor 1 – Floor VI of Central Army Hospital Gatot Soebroto Jakarta. The study was conducted from December 2011 – February 2012. The data were collected in a retrospective way for a year (January – December 2011. End-stage CRF patients who were having hemodialysis therapy and receiving ACE Inhibitor drugs or Angiotensin II Receptor Antagonist (AIIRA and receiving treatment at the General Practice Rooms at Central Army Hospital Gatot Soebroto Jakarta. During the period of January – December 2011, 84 patients were treated with end-stage CRF at the Central Army Hospital and having routine hemodialysis and 44 patients were receiving therapy with ACE Inhibitor and AIIRA. Other drugs simultaneously given with ACE Inhibitor and AIIRA were captopril-spironolactone, captopril-aspirin, captopril-allopurinol, captopril-KSR, captopril-furosemide, lisinopril-furosemide and valsartan-mefenemic acid. An increase in adverse effects of the drugs was found based on the clinical evaluation and laboratory examination. The adverse effects included hyperkalemia (9,09%, decrease in anti-hypertension effect (6,8%, acute hypotension (40%, and declining renal function (11,36%. The study identifies drug interaction

  12. Relationship between angiotensin-converting enzyme gene polymorphism and cardio-brain complications in patients with NIDDM (type 2 diabetes mellitus)

    International Nuclear Information System (INIS)

    Objective: To investigate the relationship between angiotensin-converting enzyme gene polymorphism and cardio-brain complications in patients with NIDDM. Methods: The angiotensin-converting enzyme (ACE) gene insertion/deletion polymorphism in 174 patients with NIDDM and 62 controls were examined with PCR. Results: ACE gene I/D polymorphism was closely related to coronary heart disease (angina, cardiac infarction) and cerebral infarction in diabetic patients but not with hypertension. Plasma renin activity and plasma angiotensin II levels in complicated diabetic patients with ACE D/D gene were significantly higher than those in the controls (p < 0.01). Their aldosterone and endothelin contents were not significantly different. Conclusion: Examination of ACE gene I/D polymorphism was useful for the primary prevention of cardio-brain complications in diabetic patients and helpful in the early diagnosis and therapy of coronary heart disease and cerebral infarction

  13. Functional interaction between angiotensin II receptor type 1 and chemokine (C-C motif receptor 2 with implications for chronic kidney disease.

    Directory of Open Access Journals (Sweden)

    Mohammed Akli Ayoub

    Full Text Available Understanding functional interactions between G protein-coupled receptors is of great physiological and pathophysiological importance. Heteromerization provides one important potential mechanism for such interaction between different signalling pathways via macromolecular complex formation. Previous studies suggested a functional interplay between angiotensin II receptor type 1 (AT1 and Chemokine (C-C motif Receptor 2 (CCR2. However the molecular mechanisms are not understood. We investigated AT1-CCR2 functional interaction in vitro using bioluminescence resonance energy transfer in HEK293 cells and in vivo using subtotal-nephrectomized rats as a well-established model for chronic kidney disease. Our data revealed functional heteromers of these receptors resulting in CCR2-Gαi1 coupling being sensitive to AT1 activation, as well as apparent enhanced β-arrestin2 recruitment with agonist co-stimulation that is synergistically reversed by combined antagonist treatment. Moreover, we present in vivo findings where combined treatment with AT1- and CCR2-selective inhibitors was synergistically beneficial in terms of decreasing proteinuria, reducing podocyte loss and preventing renal injury independent of blood pressure in the subtotal-nephrectomized rat model. Our findings further support a role for G protein-coupled receptor functional heteromerization in pathophysiology and provide insights into previous observations indicating the importance of AT1-CCR2 functional interaction in inflammation, renal and hypertensive disorders.

  14. Angiotensin-converting enzyme and angiotensin II receptor subtype 2 genotypes in type 1 diabetes and severe hypoglycaemia requiring emergency treatment: a case cohort study

    DEFF Research Database (Denmark)

    Pedersen-Bjergaard, Ulrik; Nielsen, Søren L; Akram, Kamran;

    2009-01-01

    AIMS: In type 1 diabetes, individual susceptibility to severe hypoglycaemia is likely to be influenced by genetic factors. We have previously reported an association of the deletion (D-) allele of the angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism and the A-allele of th...

  15. 6β-Hydroxytestosterone, a Cytochrome P450 1B1-Testosterone-Metabolite, Mediates Angiotensin II-Induced Renal Dysfunction in Male Mice.

    Science.gov (United States)

    Pingili, Ajeeth K; Thirunavukkarasu, Shyamala; Kara, Mehmet; Brand, David D; Katsurada, Akemi; Majid, Dewan S A; Navar, L Gabriel; Gonzalez, Frank J; Malik, Kafait U

    2016-05-01

    6β-Hydroxytestosterone, a cytochrome P450 1B1-derived metabolite of testosterone, contributes to the development of angiotensin II-induced hypertension and associated cardiovascular pathophysiology. In view of the critical role of angiotensin II in the maintenance of renal homeostasis, development of hypertension, and end-organ damage, this study was conducted to determine the contribution of 6β-hydroxytestosterone to angiotensin II actions on water consumption and renal function in maleCyp1b1(+/+)andCyp1b1(-/-)mice. Castration ofCyp1b1(+/+)mice orCyp1b1(-/-)gene disruption minimized the angiotensin II-induced increase in water consumption, urine output, proteinuria, and sodium excretion and decreases in urine osmolality. 6β-Hydroxytestosterone did not alter angiotensin II-induced increases in water intake, urine output, proteinuria, and sodium excretion or decreases in osmolality inCyp1b1(+/+)mice, but restored these effects of angiotensin II inCyp1b1(-/-)or castratedCyp1b1(+/+)mice.Cyp1b1gene disruption or castration prevented angiotensin II-induced renal fibrosis, oxidative stress, inflammation, urinary excretion of angiotensinogen, expression of angiotensin II type 1 receptor, and angiotensin-converting enzyme. 6β-Hydroxytestosterone did not alter angiotensin II-induced renal fibrosis, inflammation, oxidative stress, urinary excretion of angiotensinogen, expression of angiotensin II type 1 receptor, or angiotensin-converting enzyme inCyp1b1(+/+)mice. However, inCyp1b1(-/-)or castratedCyp1b1(+/+)mice, it restored these effects of angiotensin II. These data indicate that 6β-hydroxytestosterone contributes to increased thirst, impairment of renal function, and end-organ injury associated with angiotensin II-induced hypertension in male mice and that cytochrome P450 1B1 could serve as a novel target for treating renal disease and hypertension in male mice. PMID:26928804

  16. The role of AT1 and AT2 angiotensin receptors in the mechanism of apoptosis in renal tubular cells after physical exercise.

    Science.gov (United States)

    Podhorska-Okołów, M; Dziegiel, P; Gomułkiewicz, A; Dolińska-Krajewska, B; Murawska-Ciałowicz, E; Jethon, Z; Zabel, M

    2004-01-01

    Intensive physical exercise disturbs the entire homeostasis in the body and leads to changes in haemodynamic and metabolic alterations not only in skeletal muscles but also in many distant organs. In response to acute physical exercise, a decrease of the glomerular filtration may occur, followed by stimulation of the renin-angiotensin system (RAS). Recent studies have shown that both AT1 and AT2 angiotensin receptors may play a role in mediating the apoptotic process in the kidney. Our previous studies have demonstrated an occurrence of apoptosis in rat renal tubular cells after an excessive exercise. The aim of the present study was to determine the possible mechanism of exercise-induced apoptosis in rat kidney. The analysis was performed on kidneys of rats, subjected to treadmill running until exhaustion. Apoptosis was detected in paraffin sections by the TUNEL technique. The expression of AT1 and AT2 receptors in renal tubular cells was examined by immunohistochemistry and Western blot. Our results confirmed that apoptosis after physical exercise is present in renal distal tubular cells. Moreover, there was an increased expression of AT1 and AT2 receptors in distal tubular cells. These studies suggest that physical exercise may induce apoptosis by a mechanism, involving the activation of angiotensin AT1 and AT2 receptors. PMID:15638358

  17. Reporter mouse strain provides a novel look at angiotensin type-2 receptor distribution in the central nervous system.

    Science.gov (United States)

    de Kloet, Annette D; Wang, Lei; Ludin, Jacob A; Smith, Justin A; Pioquinto, David J; Hiller, Helmut; Steckelings, U Muscha; Scheuer, Deborah A; Sumners, Colin; Krause, Eric G

    2016-03-01

    Angiotensin-II acts at its type-1 receptor (AT1R) in the brain to regulate body fluid homeostasis, sympathetic outflow and blood pressure. However, the role of the angiotensin type-2 receptor (AT2R) in the neural control of these processes has received far less attention, largely because of limited ability to effectively localize these receptors at a cellular level in the brain. The present studies combine the use of a bacterial artificial chromosome transgenic AT2R-enhanced green fluorescent protein (eGFP) reporter mouse with recent advances in in situ hybridization (ISH) to circumvent this obstacle. Dual immunohistochemistry (IHC)/ISH studies conducted in AT2R-eGFP reporter mice found that eGFP and AT2R mRNA were highly co-localized within the brain. Qualitative analysis of eGFP immunoreactivity in the brain then revealed localization to neurons within nuclei that regulate blood pressure, metabolism, and fluid balance (e.g., NTS and median preoptic nucleus [MnPO]), as well as limbic and cortical areas known to impact stress responding and mood. Subsequently, dual IHC/ISH studies uncovered the phenotype of specific populations of AT2R-eGFP cells. For example, within the NTS, AT2R-eGFP neurons primarily express glutamic acid decarboxylase-1 (80.3 ± 2.8 %), while a smaller subset express vesicular glutamate transporter-2 (18.2 ± 2.9 %) or AT1R (8.7 ± 1.0 %). No co-localization was observed with tyrosine hydroxylase in the NTS. Although AT2R-eGFP neurons were not observed within the paraventricular nucleus (PVN) of the hypothalamus, eGFP immunoreactivity is localized to efferents terminating in the PVN and within GABAergic neurons surrounding this nucleus. These studies demonstrate that central AT2R are positioned to regulate blood pressure, metabolism, and stress responses. PMID:25427952

  18. The rat androgen receptor gene promoter

    NARCIS (Netherlands)

    W.M. Baarends (Willy); A.P.N. Themmen (Axel); L.J. Blok (Leen); P. Mackenbach (Petra); A.O. Brinkmann (Albert); D.N. Meijer (Dies); P.W. Faber; J. Trapman (Jan); J.A. Grootegoed (Anton)

    1990-01-01

    markdownabstractAbstract The androgen receptor (AR) is activated upon binding of testosterone or dihydrotestosterone and exerts regulatory effects on gene expression in androgen target cells. To study transcriptional regulation of the rat AR gene itself, the 5' genomic region of this gene was clon

  19. Immunohistochemical Localization of AT1a, AT1b, and AT2 Angiotensin II Receptor Subtypes in the Rat Adrenal, Pituitary, and Brain with a Perspective Commentary

    Directory of Open Access Journals (Sweden)

    Courtney Premer

    2013-01-01

    Full Text Available Angiotensin II increases blood pressure and stimulates thirst and sodium appetite in the brain. It also stimulates secretion of aldosterone from the adrenal zona glomerulosa and epinephrine from the adrenal medulla. The rat has 3 subtypes of angiotensin II receptors: AT1a, AT1b, and AT2. mRNAs for all three subtypes occur in the adrenal and brain. To immunohistochemically differentiate these receptor subtypes, rabbits were immunized with C-terminal fragments of these subtypes to generate receptor subtype-specific antibodies. Immunofluorescence revealed AT1a and AT2 receptors in adrenal zona glomerulosa and medulla. AT1b immunofluorescence was present in the zona glomerulosa, but not the medulla. Ultrastructural immunogold labeling for the AT1a receptor in glomerulosa and medullary cells localized it to plasma membrane, endocytic vesicles, multivesicular bodies, and the nucleus. AT1b and AT2, but not AT1a, immunofluorescence was observed in the anterior pituitary. Stellate cells were AT1b positive while ovoid cells were AT2 positive. In the brain, neurons were AT1a, AT1b, and AT2 positive, but glia was only AT1b positive. Highest levels of AT1a, AT1b, and AT2 receptor immunofluorescence were in the subfornical organ, median eminence, area postrema, paraventricular nucleus, and solitary tract nucleus. These studies complement those employing different techniques to characterize Ang II receptors.

  20. Inhibitory Effect of the Punica granatum Fruit Extract on Angiotensin-II Type I Receptor and Thromboxane B2 in Endothelial Cells Induced by Plasma from Preeclamptic Patients

    OpenAIRE

    Widya Kusumawati; Kusnarman Keman; Setyawati Soeharto

    2016-01-01

    This study aims to evaluate whether the Punica granatum fruit extract modulates the Angiotensin-II Type I receptor (AT1-R) and thromboxane B2 level in endothelial cells induced by plasma from preeclamptic patients. Endothelial cells were obtained from human umbilical vascular endothelial cells. At confluence, endothelial cells were divided into five groups, which included endothelial cells exposed to 2% plasma from normal pregnancy (NP), endothelial cells exposed to 2% plasma from preeclampti...

  1. Effects of the angiotensin type I receptor antagonist, losartan, on systemic and regional vascular responses to lower body negative pressure in healthy volunteers.

    OpenAIRE

    Duranteau, J; Pussard, E; Berdeaux, A; Giudicelli, J. F.

    1995-01-01

    1. The effects of a single oral dose (50 mg) of the angiotensin II AT1-receptor antagonist, losartan, on the systemic and regional vascular responses to simulated orthostatic stress by the lower body negative pressure (LBNP) technique were investigated in nine healthy volunteers, in a double-blind, placebo-controlled crossover study. 2. Arterial blood pressure remained unchanged throughout the study. Three hours after its administration and before LBNP, losartan selectively increased renal bl...

  2. Beneficial effects of an angiotensin-II receptor blocker on structural atrial reverse-remodeling in a rat model of ischemic heart failure

    OpenAIRE

    Yoon, Namsik; Cho, Jeong Gwan; Kim, Kye Hun; Park, Keun Ho; Sim, Doo Sun; Yoon, Hyun Ju; Hong, Young Joon; Park, Hyung Wook; Kim, Ju Han; Ahn, Youngkeun; Jeong, Myung Ho; Park, Jong Chun

    2013-01-01

    The remodeling of gap junctions may affect their conduction properties and contribute to the maintenance of atrial fibrillation. The significance of the role of angiotensin-II receptor blockers (ARBs) in upstream therapy is not clear. This study was performed to investigate the effects of ARBs on atrial remodeling in a heart failure model. A model of heart failure was established or sham surgery performed in 24 Sprague-Dawley male rats. The rats were divided into sham, heart failure and heart...

  3. Diabetic Retinal Neurodegeneration Is Associated With Mitochondrial Oxidative Stress and Is Improved by an Angiotensin Receptor Blocker in a Model Combining Hypertension and Diabetes

    OpenAIRE

    Silva, Kamila C.; Rosales, Mariana A.B.; Biswas, Subrata K.; Lopes de Faria, Jose B.; Lopes de Faria, Jacqueline M.

    2009-01-01

    OBJECTIVE Diabetic retinopathy displays the features of a neurodegenerative disease. Oxidative stress is involved in the pathogenesis of diabetic retinopathy. This investigation sought to determine whether hypertension exacerbates the oxidative stress, neurodegeneration, and mitochondrial dysfunction that exists in diabetic retinopathy and whether these changes could be minimized by the angiotensin II type 1 (AT1) receptor blocker (ARB) losartan. RESEARCH DESIGN AND METHODS Diabetes was induc...

  4. 受体成分蛋白在降钙素基因相关肽和血管紧张素Ⅱ对血管平滑肌细胞血管过氧化物酶1表达调控中的作用%Involvement of the receptor component protein in the regulation of vascular peroxidase-1 expression induced by calcitonin gene-related peptide and angiotensin Ⅱ in vascular smooth muscle cell

    Institute of Scientific and Technical Information of China (English)

    刘彦梅; 彭虹艳; 郭锋; 全海燕; 骆镜妃; 秦旭平

    2015-01-01

    血管紧张素Ⅱ (angiotensin Ⅱ,Ang Ⅱ)和降钙素基因相关肽(calcitonin gene-related peptide,CGRP)在血管的损伤和保护中起重要作用.为了探讨CGRP受体成分蛋白(receptor component protein,RCP)在CGRP和Ang Ⅱ对血管平滑肌细胞(vascularsmooth muscle cell,VSMC)血管过氧化物酶1(vascular peroxidase-1,VPO1)表达调控中的作用及机制,本研究采用体外培养鼠源性Al0血管平滑肌细胞株(A10VSMC),给予CGRP或/和Ang Ⅱ刺激,并用小干扰RNA (siRNA)干扰细胞RCP基因的表达,Western Blot检测RCP以及VPO1蛋白表达水平;RT-PCR检测RCP及VPO1 mRNA的表达水平.结果显示,在静止期野生型A10VSMC,CGRP和Ang Ⅱ能分别上调RCP和VPO1蛋白和mRNA表达(均P<0.05),但CGRP预孵育细胞后,Ang Ⅱ诱导的RCP和VPO1蛋白表达降低(均P<0.05);与野生型组比较,VPO1在所有RCP基因干扰组的表达均显著降低(均P<0.01).同时,在RCP基因干扰条件下,和对照组相比,CGRP处理组VPO1蛋白的表达显著增加,而Ang Ⅱ组没有明显变化;和Ang Ⅱ1组相比,CGRP与Ang Ⅱ联合作用显著增加VPOl蛋白表达,但这种作用能被抗氧化酶Catalase所抑制(P<0.05).以上结果提示,RCP可能参与CGRP或Ang Ⅱ诱导的VPO1蛋白表达;RCP可能在介导CGRP和Ang Ⅱ受体共同调控VPO1表达的信号转导整合中起一定作用.

  5. Expression of a naturally occurring angiotensin AT(1) receptor cleavage fragment elicits caspase-activation and apoptosis.

    Science.gov (United States)

    Cook, Julia L; Singh, Akannsha; DeHaro, Dawn; Alam, Jawed; Re, Richard N

    2011-11-01

    Several transmembrane receptors are documented to accumulate in nuclei, some as holoreceptors and others as cleaved receptor products. Our prior studies indicate that a population of the 7-transmembrane angiotensin type-1 receptor (AT(1)R) is cleaved in a ligand-augmented manner after which the cytoplasmic, carboxy-terminal cleavage fragment (CF) traffics to the nucleus. In the present report, we determine the precise cleavage site within the AT(1)R by mass spectrometry and Edman sequencing. Cleavage occurs between Leu(305) and Gly(306) at the junction of the seventh transmembrane domain and the intracellular cytoplasmic carboxy-terminal domain. To evaluate the function of the CF distinct from the holoreceptor, we generated a construct encoding the CF as an in-frame yellow fluorescent protein fusion. The CF accumulates in nuclei and induces apoptosis in CHO-K1 cells, rat aortic smooth muscle cells (RASMCs), MCF-7 human breast adenocarcinoma cells, and H9c2 rat cardiomyoblasts. All cell types show nuclear fragmentation and disintegration, as well as evidence for phosphotidylserine displacement in the plasma membrane and activated caspases. RASMCs specifically showed a 5.2-fold increase (P < 0.001) in CF-induced active caspases compared with control and a 7.2-fold increase (P < 0.001) in cleaved caspase-3 (Asp174). Poly(ADP-ribose)polymerase was upregulated 4.8-fold (P < 0.001) in CF expressing cardiomyoblasts and colocalized with terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL). CF expression also induces DNA laddering, the gold-standard for apoptosis in all cell types studied. CF-induced apoptosis, therefore, appears to be a general phenomenon as it is observed in multiple cell types including smooth muscle cells and cardiomyoblasts. PMID:21813711

  6. The Role of Apelin on the Alleviative Effect of Angiotensin Receptor Blocker in Unilateral Ureteral Obstruction-Induced Renal Fibrosis

    Directory of Open Access Journals (Sweden)

    Masashi Nishida

    2012-03-01

    Full Text Available Background: Apelin is a selective endogenous ligand of the APJ receptor, which genetically has closest identity to the angiotensin II type 1 receptor (AT-1. The effects of the apelin/APJ system on renal fibrosis still remain unclear. Methods: We examined the effects of the apelin/APJ system on renal fibrosis during AT-1 blockade in a mouse unilateral ureteral obstruction (UUO model. Results: We obtained the following results: (1 At UUO day 7, mRNA expressions of apelin/APJ and phosphorylations of Akt/endothelial nitric oxide synthase (eNOS in the UUO kidney were increased compared to those in the nonobstructed kidney. (2 AT-1 blockade by the treatment with losartan resulted in a further increase of apelin mRNA as well as phosphorylations of Akt/eNOS proteins, and this was accompanied by alleviated renal interstitial fibrosis, decreased myofibroblast accumulation, and a decreased number of interstitial macrophages. (3 Blockade of the APJ receptor by the treatment with F13A during losartan administration completely abrogated the effects of losartan in the activation of the Akt/eNOS pathway and the amelioration of renal fibrosis. (4 Inhibition of NOS by the treatment with L-NAME also resulted in a further increase in renal fibrosis compared to the control group. Conclusion: These results suggest that increased nitric oxide production through the apelin/APJ/Akt/eNOS pathway may, at least in part, contribute to the alleviative effect of losartan in UUO-induced renal fibrosis.

  7. Interaction of signal transduction between angiotensin AT1 and AT2 receptor subtypes in rat senescent heart

    Institute of Scientific and Technical Information of China (English)

    SHI Shu-tian; LI Yan-fang

    2007-01-01

    Background Angiotensin Ⅱ (Ang Ⅱ) acting at angiotensin AT1 receptor (AT1R) has well documented effects on cardiovascular structure such as the promotion of cardiovascular hypertrophy and fibrosis, which are believed to be opposed by angiotensin AT2 receptor (AT2R) stimulation. The expressions of AT1R and AT2R are up-regulated in senescent hearts. The purpose of this study was to investigate the interaction of signal transduction between AT1R and AT2R, and to detect whether there is any difference in the interaction in rat hearts of different age.Methods In 3.5-, 12-, 18- and 24-month-old rats, the heart cell membrane activities of protein kinase C (PKC) andtyrosine kinase were measured when AT1R and AT2R were both activated by Ang Ⅱ or just the AT1R was activated by Ang Ⅱ and PD123319. The activities of cytosolic phospholipase A2 (cPLA2) and the levels of cGMP were investigated when AT1R and AT2R were both activated by Ang Ⅱ or just the AT2R was activated by Ang Ⅱ and Iosartan.Results When AT1R and AT2R were both activated compared to when the AT1R was activated, the activities of PKC were not different in hearts from 3.5- and 12-month-old rats, but decreased significantly in 18- and 24-month-old rats; the activities of tyrosine kinase were not different in 3.5-month-old rats but decreased significantly in 12-, 18- and 24-month-old rats. The activities of cPLA2 were all decreased significantly in rats of different age when AT1R and AT2R were both activated compared to when the AT2R was activated. Treatment with Ang Ⅱ alone compared to Ang Ⅱ and losartan decreased the levels of cGMP (fmol/mg) in rats of different age (102.7±12.7 versus 86.0±8.0 in 3.5-month-old rats, P<0.05; 81.0±9.4 versus 70.0±6.3 in 12-month-old rats, P<0.05; 69.8±5.6 versus 54.2±5.3 in 18-month-old rats,P<0.01; 57.7±8.0 versus 39.0±3.0 in 24-month-old rats, P<0.01).Conclusions The activation of AT1R inhibited the signal transduction of AT2R during the aging

  8. Comparison of the antagonistic effects of different angiotensin II receptor blockers in human coronary arteries

    DEFF Research Database (Denmark)

    Pantev, Emil; Stenman, Emelie; Wackenfors, Angelica;

    2002-01-01

    undertaken to evaluate the inhibitory effects of ARBs on vasoconstriction in humans. METHODS: Vasomotor tone was analyzed in endothelium denuded, human coronary artery (HCA) segments. Ang II type 1 (AT(1)) and type 2 (AT(2)) receptor mRNA expression was examined by reverse transcriptase-polymerase chain...... presence of 100 nM losartan elicited a depression of the Ang II response to 32%. Its active metabolite, EXP 3174 (1 nM),abolished the Ang II contraction. The AT(1) receptor antagonists had the following order of blocking effect; EXP 3174 > candesartan = valsartan > losartan. The AT(2) receptor antagonist...

  9. Genetic polymorphisms of angiotensin-2 type 1 receptor and angiotensinogen and risk of renal dysfunction and coronary heart disease in type 2 diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Hu Frank B

    2009-03-01

    Full Text Available Abstract Background Increased activation of the renin-angiotensin system (RAS may be important in promoting coronary heart disease (CHD and renal dysfunction, but limited data are available on associations between angiotensin type 1 receptor (AGT1R and angiotensinogen (AGT genotypes in type 2 diabetes. Methods Study participants were diabetics from the Health Professionals Follow-Up Study (HPFS and the Nurses' Health Study (NHS. We analyzed single nucleotide polymorphisms (SNPs associated with cardiovascular pathophysiology (including AGT1R T573C, AGT1R A1166C, and AGT M235T and presence of renal dysfunction (eGFR2 or history of CHD. Results The AGT1R 1166 C-allele was associated with eGFR2 (multivariable OR 1.63 [1.01, 2.65] in the HPFS men (n = 733 and in the combined dataset (n = 1566 (OR 1.42 [1.02, 1.98]. The AGT1R 1166 C-allele was also associated with CHD in men (OR 1.57 [1.10, 2.24]. In NHS women (n = 833, AGT 235T-allele was associated with CHD (OR 1.72 [1.20, 2.47]. Removal of hypertension from the fully adjusted models did not influence results, suggesting that the associations may not be mediated by hypertension. There were significant interactions between sex and AGT1R 1166 C-allele (p = 0.008 and AGT M235T (p = 0.03 in models for CHD. No significant associations were seen between AGT1R T573 C-allele and renal dysfunction or CHD. Conclusion Polymorphisms in AGT1R and AGT genes are associated with renal dysfunction and CHD in type 2 diabetes and further support the important role of the RAS in these complications. Sex may modify associations between AGT1R 1166 C-allele and AGT 235T and CHD in type 2 diabetes.

  10. Deletion of angiotensin II type 2 receptor accelerates adipogenesis in murine mesenchymal stem cells via Wnt10b/beta-catenin signaling.

    Science.gov (United States)

    Matsushita, Kenichi; Wu, Yaojiong; Pratt, Richard E; Dzau, Victor J

    2016-08-01

    Recent evidence suggests that the renin-angiotensin system (RAS) has a vital role in adipocyte biology and the pathophysiology of metabolic syndrome. Obesity is the main culprit of metabolic syndrome; and mesenchymal stem cells (MSCs) have been forwarded as a major source of adipocyte generation. Previously, we reported that MSCs have a local RAS and that pharmacological blockade of angiotensin II type 2 receptor (AT2R) promotes adipogenesis in human MSCs. However, the definitive roles of AT2R and how AT2R functions in adipogenesis remains unknown. To this end, we employed AT2R-null murine MSCs to characterize how AT2R affects the differentiation of MSCs into adipocytes. Murine MSCs were isolated from AT2R-null mice and wild-type littermates, grown to confluency, and then differentiated into adipocytes. Adipogenesis was quantitated by assessing the lipid droplet accumulation. Using the lipophilic fluorescent dye, the AT2R-null cells showed significantly increased total fluorescence (261.6±49.6% vs littermate) on day 7. Oil red O staining followed by extraction of the absorbed dye and measurement of the absorbance on day 14 also exhibited significantly increased lipid droplet accumulation in the AT2R-null cells (202.7±14.1% vs littermate). We also examined the expression of adipogenic marker genes by quantitative RT-PCR. The AT2R-null group exhibited significantly increased expression of PPAR-gamma, fatty acid synthase, and adiponectin (vs littermate). We further examined the role of Wnt10b/beta-catenin signaling, which reportedly has an important inhibitory role in adipogenesis. The AT2R-null group exhibited significantly decreased Wnt10b expression accompanied by decreased beta-catenin (vs littermate). Our results thus revealed that the AT2R inhibits adipogenic differentiation in murine MSCs. Moreover, this inhibitory effect is associated with Wnt10b/beta-catenin signaling. These results provide important insights into the pathophysiology of obesity and obesity

  11. Angiotensin II modulates interleukin-1{beta}-induced inflammatory gene expression in vascular smooth muscle cells via interfering with ERK-NF-{kappa}B crosstalk

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Shanqin [Vascular Biology Unit, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA (United States); Zhi, Hui [Cardiovascular Division, Department of Medicine, Brigham and Women' s Hospital, Harvard Medical School, Boston, MA (United States); Hou, Xiuyun [Vascular Biology Unit, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA (United States); Jiang, Bingbing, E-mail: bjiang1@rics.bwh.harvard.edu [Vascular Biology Unit, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA (United States); Cardiovascular Division, Department of Medicine, Brigham and Women' s Hospital, Harvard Medical School, Boston, MA (United States)

    2011-07-08

    Highlights: {yields} We examine how angiotensin II modulates ERK-NF-{kappa}B crosstalk and gene expression. {yields} Angiotensin II suppresses IL-1{beta}-induced prolonged ERK and NF-{kappa}B activation. {yields} ERK-RSK1 signaling is required for IL-1{beta}-induced prolonged NF-{kappa}B activation. {yields} Angiotensin II modulates NF-{kappa}B responsive genes via regulating ERK-NF-{kappa}B crosstalk. {yields} ERK-NF-{kappa}B crosstalk is a novel mechanism regulating inflammatory gene expression. -- Abstract: Angiotensin II is implicated in cardiovascular diseases, which is associated with a role in increasing vascular inflammation. The present study investigated how angiotensin II modulates vascular inflammatory signaling and expression of inducible nitric oxide synthase (iNOS) and vascular cell adhesion molecule (VCAM)-1. In cultured rat aortic vascular smooth muscle cells (VSMCs), angiotensin II suppressed interleukin-1{beta}-induced prolonged phosphorylation of extracellular signal-regulated kinase (ERK) and ribosomal S6 kinase (RSK)-1, and nuclear translocation of nuclear factor (NF)-{kappa}B, leading to decreased iNOS but enhanced VCAM-1 expression, associated with an up-regulation of mitogen-activated protein kinase phosphatase-1 expression. Knock-down of RSK1 selectively down regulated interleukin-1{beta}-induced iNOS expression without influencing VCAM-1 expression. In vivo experiments showed that interleukin-1{beta}, iNOS, and VCAM-1 expression were detectable in the aortic arches of both wild-type and apolipoprotein E-deficient (ApoE{sup -/-}) mice. VCAM-1 and iNOS expression were higher in ApoE{sup -/-} than in wild type mouse aortic arches. Angiotensin II infusion (3.2 mg/kg/day, for 6 days, via subcutaneous osmotic pump) in ApoE{sup -/-} mice enhanced endothelial and adventitial VCAM-1 and iNOS expression, but reduced medial smooth muscle iNOS expression associated with reduced phosphorylation of ERK and RSK-1. These results indicate that angiotensin

  12. Differential extracellular signal-regulated kinases 1 and 2 activation by the angiotensin type 1 receptor supports distinct phenotypes of cardiac myocytes

    DEFF Research Database (Denmark)

    Aplin, Mark; Christensen, Gitte Lund; Schneider, Mikael;

    2007-01-01

    The angiotensin II (AngII) type 1 receptor (AT(1)R) is a seven-transmembrane receptor well established to activate extracellular signal-regulated kinases 1 and 2 (ERK1/2) by discrete G protein-dependent and beta-arrestin2-dependent pathways. The biological importance of this, however, remains obs...... obscure. Application of the modified analogue [Sar(1), Ile(4), Ile(8)]-AngII ([SII] AngII) allowed us to dissect the two pathways of ERK1/2 activation in native cardiac myocytes. Although cytosol-retained, the beta-arrestin2-bound pool of ERK1/2 represents an active signalling component...

  13. Pharmacogenetic risk stratification in angiotensin-converting enzyme inhibitor-treated patients with congestive heart failure

    DEFF Research Database (Denmark)

    Nelveg-Kristensen, Karl Emil; Busk Madsen, Majbritt; Torp-Pedersen, Christian;

    2015-01-01

    SNPs of the angiotensin-converting enzyme gene (rs4343) and ABO blood group genes (rs495828 and rs8176746). METHODS: Danish patients with CHF enrolled in the previously reported Echocardiography and Heart Outcome Study were included. Subjects were genotyped and categorized according to pharmacogenetic......BACKGROUND: Evidence for pharmacogenetic risk stratification of angiotensin-converting enzyme inhibitor (ACEI) treatment is limited. Therefore, in a cohort of ACEI-treated patients with congestive heart failure (CHF), we investigated the predictive value of two pharmacogenetic scores that...... previously were found to predict ACEI efficacy in patients with ischemic heart disease and hypertension, respectively. Score A combined single nucleotide polymorphisms (SNPs) of the angiotensin II receptor type 1 gene (rs275651 and rs5182) and the bradykinin receptor B1 gene (rs12050217). Score B combined...

  14. Pharmacokinetic drug-drug interaction assessment between LCZ696, an angiotensin receptor neprilysin inhibitor, and hydrochlorothiazide, amlodipine, or carvedilol.

    Science.gov (United States)

    Hsiao, Hsiu-Ling; Langenickel, Thomas Heiko; Greeley, Michael; Roberts, John; Zhou, Wei; Pal, Parasar; Rebello, Sam; Rajman, Iris; Sunkara, Gangadhar

    2015-11-01

    LCZ696 is a first-in-class angiotensin receptor neprilysin inhibitor in development for treatments of hypertension and heart failure indications. In 3 separate studies, pharmacokinetic drug-drug interactions (DDIs) potential was assessed when LCZ696 was coadministered with hydrochlorothiazide (HCTZ), amlodipine, or carvedilol. The studies used a open-label, single-sequence, 3-period, crossover design in healthy subjects. Blood samples were collected to determine the pharmacokinetic parameters of LCZ696 analytes (AHU377, LBQ657, and valsartan), HCTZ, amlodipine, or carvedilol (R[+]- and S[-]-carvedilol) for statistical analysis. When coadministered LCZ696 with HCTZ, the 90% CIs of the geometric mean ratios of AUCtau,ss of HCTZ and that of LBQ657 were within a 0.80-1.25 interval, whereas HCTZ Cmax,ss decreased by 26%, LBQ657 Cmax,ss increased by 19%, and the AUCtau,ss and Cmax,ss of valsartan increased by 14% and 16%, respectively. Pharmacokinetics of amlodipine, R(+)- and S(-)-carvedilol, or LBQ657 were not altered after coadministration of LCZ696 with amlodipine or carvedilol. Coadministration of LCZ696 400 mg once daily (qd) with HCTZ 25 mg qd, amlodipine 10 mg qd, or carvedilol 25 mg twice a day (bid) had no clinically relevant pharmacokinetic drug-drug interactions. LCZ696, HCTZ, amlodipine, and carvedilol were safe and well tolerated when given alone or concomitantly in the investigated studies. PMID:27137712

  15. The Effect of an Angiotensin Receptor Blocker on Arterial Stiffness in Type 2 Diabetes Mellitus Patients with Hypertension

    Directory of Open Access Journals (Sweden)

    Ji Hyun Kim

    2011-06-01

    Full Text Available BackgroundHypertension and type 2 diabetes mellitus are major risk factors for cardiovascular disease. This study analyzed the changes in central aortic waveforms and pulse wave velocity as well as related parameters after treatment with valsartan, an angiotensin II type 1 receptor blocker, in patients with type 2 diabetes and hypertension.MethodsWe used pulse wave analysis to measure central aortic waveform in a total of 98 subjects. In 47 of these patients, pulse wave velocity measurements were obtained before and after 12 weeks of treatment with valsartan.ResultsIn the central aortic waveform analysis, the aortic pulse pressure and augmentation index were significantly decreased after valsartan treatment, as was the aortic pulse wave velocity. Factors contributing to the improvement in pulse wave velocity were the fasting blood glucose and haemoglobin A1c levels.ConclusionShort-term treatment with valsartan improves arterial stiffness in patients with type 2 diabetes and hypertension, and the glucose status at baseline was associated with this effect.

  16. A PROSPECTIVE STUDY OF EFFECT OF TELMISARTAN (ANGIOTENSIN II RECEPTOR BLOCKER ON METABOLIC PARAMETERS IN HYPERTENSIVE PATIENTS WITH METABOLIC SYNDROME

    Directory of Open Access Journals (Sweden)

    Somesekhar

    2016-04-01

    Full Text Available BACKGROUND The metabolic syndrome is currently a major worldwide epidemic. It strongly associates with obesity, insulin resistance, type 2 diabetes, and cardiovascular diseases, which are major pathologies contributing to mortality and morbidity worldwide. The effect of PPAR-y on metabolic syndrome is significant it is critical regulator of adipogenesis the gain in PPAR-y is resulted in obesity but loss of PPAR–y by mutation is associated with loss of weight and insulin resistance. Telmisartan is an orally active, long-acting, non-peptide angiotensin type 1 (ATI receptor blocker. In addition to this, it has been identified as partial agonist/selective modulator of the nuclear hormone receptor PPAR-y. MATERIAL AND METHOD This is a prospective, randomised and open labelled 16 weeks study conducted in the Dept. of General Medicine, Konaseema Institute of Medical Science, Amalapuram. Present study is designed to study the effect of telmisartan on various metabolic parameters in hypertensive patients who fulfilled the criteria of metabolic syndrome. RESULT There was statistically significant change in all parameters most important was lipid profile; LDL concentration was decreased from 139.2 mg/dL to 120.2 mg/dL. Baseline triglyceride concentration was 161.0 mg/dL which was changed 152.8 mg/dL Total cholesterol was decreased from 203.2 to 193.8 mg/dL. CONCLUSION In our study, we have also found that use of telmisartan is associated with decrease in lipid concentration in addition to its effect on blood pressure regulation. But a long term study with high dose required of this drug is required because safety profile of this drug is better than thiazolidinedione. Financial part of this study is our limitation.

  17. Prostaglandin E-prostanoid4 receptor mediates angiotensin II-induced (pro)renin receptor expression in the rat renal medulla.

    Science.gov (United States)

    Wang, Fei; Lu, Xiaohan; Peng, Kexin; Du, Yaomin; Zhou, Shu-Feng; Zhang, Aihua; Yang, Tianxin

    2014-08-01

    Angiotensin II (Ang II) stimulates (pro)renin receptor (PRR) expression in the renal collecting duct, triggering the local renin response in the distal nephron. Our recent study provided evidence for involvement of cyclooxygenase-2-prostaglandin E2 pathway in Ang II-dependent stimulation of PRR expression in the collecting duct. Here, we tested the role of E-prostanoid (EP) subtypes acting downstream of cyclooxygenase-2 in this phenomenon. In primary rat inner medullary collecting duct cells, Ang II treatment for 12 hours induced a 1.8-fold increase in the full-length PRR protein expression. To assess the contribution of EP receptor, the cell was pretreated with specific EP receptor antagonists: SC-51382 (for EP1), L-798106 (for EP3), L-161982 (for EP4), and ONO-AE3-208 (ONO, a structurally distinct EP4 antagonist). The upregulation of PRR expression by Ang II was consistently abolished by L-161982 and ONO and partially suppressed by SC-51382 but was unaffected by L-798106. The PRR expression was also significantly elevated by the EP4 agonist CAY10598 in the absence of Ang II. Sprague-Dawley rats were subsequently infused for 1 or 2 weeks with vehicle, Ang II alone, or in combination with ONO. Ang II infusion induced parallel increases in renal medullary PRR protein and renal medullary and urinary renin activity and total renin content, all of which were blunted by ONO. Both tail cuff plethysmography and telemetry demonstrated attenuation of Ang II hypertension by ONO. Overall, these results have established a crucial role of the EP4 receptor in mediating the upregulation of renal medullary PRR expression and renin activity during Ang II hypertension. PMID:24866147

  18. Acute ethanol intake induces superoxide anion generation and mitogen-activated protein kinase phosphorylation in rat aorta: A role for angiotensin type 1 receptor

    International Nuclear Information System (INIS)

    Ethanol intake is associated with increase in blood pressure, through unknown mechanisms. We hypothesized that acute ethanol intake enhances vascular oxidative stress and induces vascular dysfunction through renin–angiotensin system (RAS) activation. Ethanol (1 g/kg; p.o. gavage) effects were assessed within 30 min in male Wistar rats. The transient decrease in blood pressure induced by ethanol was not affected by the previous administration of losartan (10 mg/kg; p.o. gavage), a selective AT1 receptor antagonist. Acute ethanol intake increased plasma renin activity (PRA), angiotensin converting enzyme (ACE) activity, plasma angiotensin I (ANG I) and angiotensin II (ANG II) levels. Ethanol induced systemic and vascular oxidative stress, evidenced by increased plasma thiobarbituric acid-reacting substances (TBARS) levels, NAD(P)H oxidase‐mediated vascular generation of superoxide anion and p47phox translocation (cytosol to membrane). These effects were prevented by losartan. Isolated aortas from ethanol-treated rats displayed increased p38MAPK and SAPK/JNK phosphorylation. Losartan inhibited ethanol-induced increase in the phosphorylation of these kinases. Ethanol intake decreased acetylcholine-induced relaxation and increased phenylephrine-induced contraction in endothelium-intact aortas. Ethanol significantly decreased plasma and aortic nitrate levels. These changes in vascular reactivity and in the end product of endogenous nitric oxide metabolism were not affected by losartan. Our study provides novel evidence that acute ethanol intake stimulates RAS activity and induces vascular oxidative stress and redox-signaling activation through AT1-dependent mechanisms. These findings highlight the importance of RAS in acute ethanol-induced oxidative damage. -- Highlights: ► Acute ethanol intake stimulates RAS activity and vascular oxidative stress. ► RAS plays a role in acute ethanol-induced oxidative damage via AT1 receptor activation. ► Translocation of p47

  19. Acute ethanol intake induces superoxide anion generation and mitogen-activated protein kinase phosphorylation in rat aorta: A role for angiotensin type 1 receptor

    Energy Technology Data Exchange (ETDEWEB)

    Yogi, Alvaro; Callera, Glaucia E. [Kidney Research Centre, Ottawa Hospital Research Institute, University of Ottawa, Ontario (Canada); Mecawi, André S. [Department of Physiology, Faculty of Medicine of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, SP (Brazil); Batalhão, Marcelo E.; Carnio, Evelin C. [Department of General and Specialized Nursing, College of Nursing of Ribeirão Preto, USP, São Paulo (Brazil); Antunes-Rodrigues, José [Department of Physiology, Faculty of Medicine of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, SP (Brazil); Queiroz, Regina H. [Department of Clinical, Toxicological and Food Science Analysis, Faculty of Pharmaceutical Sciences, USP, São Paulo (Brazil); Touyz, Rhian M. [Kidney Research Centre, Ottawa Hospital Research Institute, University of Ottawa, Ontario (Canada); Tirapelli, Carlos R., E-mail: crtirapelli@eerp.usp.br [Department of Psychiatric Nursing and Human Sciences, Laboratory of Pharmacology, College of Nursing of Ribeirão Preto, USP, Ribeirão Preto, SP (Brazil)

    2012-11-01

    Ethanol intake is associated with increase in blood pressure, through unknown mechanisms. We hypothesized that acute ethanol intake enhances vascular oxidative stress and induces vascular dysfunction through renin–angiotensin system (RAS) activation. Ethanol (1 g/kg; p.o. gavage) effects were assessed within 30 min in male Wistar rats. The transient decrease in blood pressure induced by ethanol was not affected by the previous administration of losartan (10 mg/kg; p.o. gavage), a selective AT{sub 1} receptor antagonist. Acute ethanol intake increased plasma renin activity (PRA), angiotensin converting enzyme (ACE) activity, plasma angiotensin I (ANG I) and angiotensin II (ANG II) levels. Ethanol induced systemic and vascular oxidative stress, evidenced by increased plasma thiobarbituric acid-reacting substances (TBARS) levels, NAD(P)H oxidase‐mediated vascular generation of superoxide anion and p47phox translocation (cytosol to membrane). These effects were prevented by losartan. Isolated aortas from ethanol-treated rats displayed increased p38MAPK and SAPK/JNK phosphorylation. Losartan inhibited ethanol-induced increase in the phosphorylation of these kinases. Ethanol intake decreased acetylcholine-induced relaxation and increased phenylephrine-induced contraction in endothelium-intact aortas. Ethanol significantly decreased plasma and aortic nitrate levels. These changes in vascular reactivity and in the end product of endogenous nitric oxide metabolism were not affected by losartan. Our study provides novel evidence that acute ethanol intake stimulates RAS activity and induces vascular oxidative stress and redox-signaling activation through AT{sub 1}-dependent mechanisms. These findings highlight the importance of RAS in acute ethanol-induced oxidative damage. -- Highlights: ► Acute ethanol intake stimulates RAS activity and vascular oxidative stress. ► RAS plays a role in acute ethanol-induced oxidative damage via AT{sub 1} receptor activation.

  20. The bradykinin BK2 receptor mediates angiotensin II receptor type 2 stimulated rat duodenal mucosal alkaline secretion

    Directory of Open Access Journals (Sweden)

    Helander Herbert F

    2003-02-01

    Full Text Available Abstract Background This study investigates bradykinin and nitric oxide as potential mediators of AT2-receptor-stimulated duodenal mucosal alkaline secretion. Duodenal mucosal alkaline secretion was measured in methohexital- and α-chloralose-anaesthetised rats by means of in situ pH-stat titration. Immunohistochemistry and Western blot were used to identify the BK2 receptors. Results The AT2 receptor agonist CGP42112A (0.1 μg kg-1 min-1 administered intravenously increased the duodenal mucosal alkaline secretion by ~50 %. This increase was sensitive to the selective BK2 receptor blocker HOE140 (100 ng/kg iv, but not to luminal administration of the NOS blocker L-NAME (0.3 mM. Mean arterial pressure did not differ between groups during the procedures. Immunohistochemistry showed a distinct staining of the crypt epithelium and a moderate staining of basal cytoplasm in villus enterocytes. Conclusion The results suggest that the AT2-receptor-stimulated alkaline secretion is mediated via BK2 receptors located in the duodenal cryptal mucosal epithelium.

  1. Biased signaling of the angiotensin II type 1 receptor can be mediated through distinct mechanisms

    DEFF Research Database (Denmark)

    Bonde, Marie Mi; Hansen, Jonas Tind; Sanni, Samra Joke; Gammeltoft, Steen; Haunsø, Stig; Lyngsø, Christina; Hansen, Jakob Lerche

    2010-01-01

    Seven transmembrane receptors (7TMRs) can adopt different active conformations facilitating a selective activation of either G protein or β-arrestin-dependent signaling pathways. This represents an opportunity for development of novel therapeutics targeting selective biological effects of a given...

  2. Biased signaling of the angiotensin II type 1 receptor can be mediated through distinct mechanisms

    DEFF Research Database (Denmark)

    Bonde, Marie Mi; Hansen, Jonas Tind; Sanni, Samra Joke; Gammeltoft, Steen; Haunsø, Stig; Lyngsø, Christina; Hansen, Jakob Lerche

    2010-01-01

    Seven transmembrane receptors (7TMRs) can adopt different active conformations facilitating a selective activation of either G protein or ß-arrestin-dependent signaling pathways. This represents an opportunity for development of novel therapeutics targeting selective biological effects of a given...

  3. Angiotensin II Type 2-Receptor Agonist C21 Reduces Proteinuria and Oxidative Stress in Kidney of High-Salt-Fed Obese Zucker Rats.

    Science.gov (United States)

    Patel, Sanket N; Ali, Quaisar; Hussain, Tahir

    2016-05-01

    Oxidative and nitrosative stress have been implicated in high-sodium diet (HSD)-related hypertensive renal injury. In this study, we investigated angiotensin II type 2-receptor-mediated renoprotection in obese Zucker rats fed HSD. Obese Zucker rats were fed normal sodium diet or HSD 4%, for 14 days, with/without angiotensin II type 2-receptor agonist C21, delivered subcutaneously via osmotic pump, 1 mg/kg per day. Compared with normal sodium diet controls, HSD rats exhibited increase in cortical nicotinamide adenine dinucleotide phosphate oxidase activity, urinary H2O2, and 8-isoprostanes, which were associated with severe glomerulosclerosis, interstitial fibrosis, decline in estimated glomerular filtration rate, and an increase in urinary leak and activity ofN-acetyl-β-d-glucosaminidase, a lysosomal enzyme and a marker of tubular damage. These changes were improved by C21 treatment. Cortical expression of endothelial nitric oxide synthase, phospho-endothelial nitric oxide synthase (Ser(1177)), and plasma nitrites were reduced after HSD intake, whereas nitrosative stress (3-nitrotyrosine) and enzymatic defense (superoxide dismutase-to-catalase activity) remained unaltered. However, C21 preserved plasma nitrites in HSD-fed obese Zucker rat. C21 treatment reduced protein-to-creatinine, albumin-to-creatinine, as well as fractional excretion of protein and albumin in HSD-fed obese Zucker rat, which is independent of changes in protein recycling receptors, megalin, and cubilin. HSD intake also altered renal excretory and reabsorptive capacity as evident by elevated plasma urea nitrogen-to-creatinine and fractional excretion of urea nitrogen, and reduced urine-to-plasma creatinine, which were modestly, but insignificantly, improved by C21 treatment. Together results demonstrate that angiotensin II type 2-receptor activation protects against HSD-induced kidney damage in obesity plausibly by reducing nicotinamide adenine dinucleotide phosphate oxidase activity and

  4. Nuclear Receptor Genes - Regulation and Evolution

    OpenAIRE

    Sharma, Yogita

    2016-01-01

    Nuclear receptors are transcription factors that typically bind ligands in order to regulate the expression level of their target genes. Members of this family work with their co-regulators and repressors to maintain a variety of biological and physiological processes such as metabolism, development and reproduction. Nuclear receptors are promising drug targets and have therefore attracted immense attention in recent decades in the field of pharmacology. Irregular expression of nuclear recept...

  5. Chromosomal organization of adrenergic receptor genes

    International Nuclear Information System (INIS)

    The adrenergic receptors (ARs) (subtypes α1, α2, β1, and β2) are a prototypic family of guanine nucleotide binding regulatory protein-coupled receptors that mediate the physiological effects of the hormone epinephrine and the neurotransmitter norepinephrine. The authors have previously assigned the genes for β2-and α2-AR to human chromosomes 5 and 10, respectively. By Southern analysis of somatic cell hybrids and in situ chromosomal hybridization, they have now mapped the α1-AR gene to chromosome 5q32→q34, the same position as β2-AR, and the β1-AR gene to chromosome 10q24→q26, the region where α2-AR, is located. In mouse, both α2-and β1-AR genes were assigned to chromosome 19, and the α1-AR locus was localized to chromosome 11. Pulsed field gel electrophoresis has shown that the α1-and β2-AR genes in humans are within 300 kilobases (kb) and the distance between the α2- and β1-AR genes is <225 kb. The proximity of these two pairs of AR genes and the sequence similarity that exists among all the ARs strongly suggest that they are evolutionarily related. Moreover, they likely arose from a common ancestral receptor gene and subsequently diverged through gene duplication and chromosomal duplication to perform their distinctive roles in mediation the physiological effects of catecholamines. The AR genes thus provide a paradigm for understanding the evolution of such structurally conserved yet functionally divergent families off receptor molecules

  6. Beta-blocker, angiotensin-converting enzyme inhibitor/angiotensin receptor blocker, nitrate-hydralazine, diuretics, aldosterone antagonist, ivabradine, devices and digoxin (BANDAID(2) ): an evidence-based mnemonic for the treatment of systolic heart failure.

    Science.gov (United States)

    Chia, N; Fulcher, J; Keech, A

    2016-06-01

    Heart failure causes significant morbidity and mortality, with recognised underutilisation rates of guideline-based therapies. Our aim was to review current evidence for heart failure treatments and derive a mnemonic summarising best practice, which might assist physicians in patient care. Treatments were identified for review from multinational society guidelines and recent randomised trials, with a primary aim of examining their effects in systolic heart failure patients on mortality, hospitalisation rates and symptoms. Secondary aims were to consider other clinical benefits. MEDLINE and EMBASE were searched using a structured keyword strategy and the retrieved articles were evaluated methodically to produce an optimised reference list for each treatment. We devised the mnemonic BANDAID (2) , standing for beta-blocker, angiotensin-converting enzyme inhibitor/angiotensin receptor blocker, nitrate-hydralazine (or potentially neprilysin inhibitor), diuretics, aldosterone antagonist, ivabradine, devices (automatic implantable cardioverter defibrillator, cardiac resynchronisation therapy or both) and digoxin as a representation of treatments with strong evidence for their use in systolic heart failure. Treatment with omega-3 fatty acids, statins or anti-thrombotic therapies has limited benefits in a general heart failure population. Adoption of this mnemonic for current evidence-based treatments for heart failure may help improve prescribing rates and patient outcomes in this debilitating, high mortality condition. PMID:26109136

  7. Activation of intracellular angiotensin AT2 receptors induces rapid cell death in human uterine leiomyosarcoma cells

    DEFF Research Database (Denmark)

    Zhao, Yi; Lützen, Ulf; Fritsch, Jürgen; Zuhayra, Maaz; Schütze, Stefan; Steckelings, Ulrike Muscha; Recarti, Chiara; Namsolleck, Pawel; Unger, Thomas; Culman, Juraj

    2015-01-01

    -peptide AT2 receptor agonist, Compound 21 (C21) penetrates the cell membrane of quiescent SK-UT-1 cells, activates intracellular AT2 receptors and induces rapid cell death; approximately 70% of cells died within 24 h. The cells, which escaped from the cell death, displayed activation of the mitochondrial...... apoptotic pathway, i. e. down-regulation of the Bcl-2 protein, induction of the Bax protein and activation of caspase-3. All quiescent SK-UT-1 cells died within 5 days after treatment with a single dose of C21. C21 was devoid of cytotoxic effects in proliferating SK-UT-1 cells and in quiescent HutSMC. Our...

  8. Vitamin D Receptor Attenuates Renal Fibrosis by Suppressing the Renin-Angiotensin System

    OpenAIRE

    Zhang, Yan; Kong, Juan; Dilip K. Deb; Chang, Anthony; Li, Yan Chun

    2010-01-01

    Analogs of vitamin D attenuate renal injury in several models of kidney disease, but the mechanism underlying this renoprotective effect is unknown. To address the role of the vitamin D receptor (VDR) in renal fibrogenesis, we subjected VDR-null mice to unilateral ureteral obstruction for 7 days. Compared with wild-type mice, VDR-null mice developed more severe renal damage in the obstructed kidney, with marked tubular atrophy and interstitial fibrosis. Significant induction of extracellular ...

  9. Angiotensin II type 1 receptors and systemic hemodynamic and renal responses to stress and altered blood volume in conscious rabbits

    Directory of Open Access Journals (Sweden)

    RogerGeorgeEvans

    2011-07-01

    Full Text Available We examined how systemic blockade of type 1 angiotensin (AT1- receptors affects reflex control of the circulation and the kidney. In conscious rabbits, the effects of candesartan on responses of systemic and renal hemodynamics and renal excretory function to acute hypoxia, mild hemorrhage and plasma volume expansion were tested. Candesartan reduced resting mean arterial pressure (MAP, -8 ± 2% without significantly altering cardiac output (CO, increased renal blood flow (RBF, +38 ± 9% and reduced renal vascular resistance (RVR, -32 ± 6%. Glomerular filtration rate (GFR was not significantly altered but sodium excretion (UNa+V increased four-fold. After vehicle treatment, hypoxia (10% inspired O2 for 30 min did not significantly alter MAP or CO, but reduced HR (-17 ± 6%, increased RVR (+33 ± 16% and reduced GFR (-46 ± 16% and UNa+V (-41 ± 17%. Candesartan did not significantly alter these responses. After vehicle treatment, plasma volume expansion increased CO (+35 ± 7%, reduced total peripheral resistance (TPR, -26 ± 5%, increased RBF (+62 ± 23% and reduced RVR (-32 ± 9%, but did not significantly alter MAP or HR. It also increased UNa+V (803 ± 184% yet reduced GFR (-47 ± 9%. Candesartan did not significantly alter these responses. After vehicle treatment, mild hemorrhage did not significantly alter MAP but increased HR (+16 ± 3%, reduced CO (-16 ± 4% and RBF (-18 ± 6%, increased TPR (+18 ± 4% and tended to increase RVR (+18 ± 9%, P = 0.1, but had little effect on GFR or UNa+V. But after candesartan treatment MAP fell during hemorrhage (-19 ± 1%, while neither TPR nor RVR increased, and GFR (-64 ± 18% and UNa+V (-83 ± 10% fell. AT1-receptor activation supports MAP and GFR during hypovolemia. But AT1-receptors appear to play little role in the renal vasoconstriction, hypofiltration and antinatriuresis accompanying hypoxia, or the systemic and renal vasodilatation and natriuresis accompanying plasma volume expansion.

  10. Orphan nuclear receptor small heterodimer partner inhibits angiotensin II-stimulated PAI-1 expression in vascular smooth muscle cells

    OpenAIRE

    Lee, Kyeong-Min; Seo, Hye-Young; Kim, Mi-Kyung; Min, Ae-Kyung; Ryu, Seong-Yeol; Kim, Yoon-Nyun; Park, Young Joo; Choi, Hueng-Sik; Lee, Ki-Up; Park, Wan-Ju; Park, Keun-Gyu; Lee, In-Kyu

    2009-01-01

    Angiotensin II is a major effector molecule in the development of cardiovascular disease. In vascular smooth muscle cells (VSMCs), angiotensin II promotes cellular proliferation and extracellular matrix accumulation through the upregulation of plasminogen activator inhibitor-1 (PAI-1) expression. Previously, we demonstrated that small heterodimer partner (SHP) represses PAI-1 expression in the liver through the inhibition of TGF-β signaling pathways. Here, we investigated whether SHP inhibite...

  11. Interaction and Relationship Between Angiotensin Converting Enzyme Gene and Environmental Factors Predisposing to Essential Hypertension in Mongolian Population of China

    Institute of Scientific and Technical Information of China (English)

    QUN XU; HUA FENG; SHUANG-LIAN BAI; HAI-HUA PANG; GUI-RONG HUANG; MING-WU FANG; YONG-HONG ZHANG; ZHENG-LAI WU; CHANG-CHUN QIU; YAN-HUA WANG; WEI-JUN TONG; MING-LIANG GU; GANG WU; BATU BUREN; YONG-YUE LIU; JIAN WANG; YONG-SHAN LI

    2004-01-01

    Objective To investigate the association of specific functional gene ACE (I/D) variants of the renin-angiotensin system with essential hypertension (EH) and interaction between ACE (I/D) gene and risk factors for EH in a genetically homogenous Mongolia rural population of China. Methods Individuals (n=1099) were recruited from general population of Kezuohouqi Banner in Inner Mongolian Autonomous Region. Results The association was found between ACE genotype DD plus ID and EH, with an interaction between ACE genotype DD plus ID and cigarette smoking in an additive model. Cigarette smoking index and ACE gene showed a low exposure-gene (LEG) effect on EH, with interaction indices from 7.10 to 1.16. Interaction between ACE genotype DD plus ID and alcohol drinking on EH appeared an additive model. Alcohol drinking index and ACE gene showed a low exposure-gene (LEG) effect on EH, with interaction indices from 1.66 to 1.09. BMI and ACE gene showed a low exposure-gene (LEG) effect on EH, with interaction indices from 6.15 to 2.49. Interactions between ACE genotype and WHR on EH showed a multiplicative model. In a short, there was an interaction between ACE gene and cigarette smoking, alcohol drinking and BMI on EH, especially in a low dose-exposure effect. Conclusion It is important for individuals who carry ACE D allele gene to prevent EH, and furthermore, to prevent and control coronary heart disease, in a view of population-based prevention.

  12. Lipid rafts are required for signal transduction by angiotensin II receptor type 1 in neonatal glomerular mesangial cells

    International Nuclear Information System (INIS)

    Angiotensin II (ANG-II) receptors (AGTRs) contribute to renal physiology and pathophysiology, but the underlying mechanisms that regulate AGTR function in glomerular mesangium are poorly understood. Here, we show that AGTR1 is the functional AGTR subtype expressed in neonatal pig glomerular mesangial cells (GMCs). Cyclodextrin (CDX)-mediated cholesterol depletion attenuated cell surface AGTR1 protein expression and ANG-II-induced intracellular Ca2+ ([Ca2+]i) elevation in the cells. The COOH-terminus of porcine AGTR1 contains a caveolin (CAV)-binding motif. However, neonatal GMCs express CAV-1, but not CAV-2 and CAV-3. Colocalization and in situ proximity ligation assay detected an association between endogenous AGTR1 and CAV-1 in the cells. A synthetic peptide corresponding to the CAV-1 scaffolding domain (CSD) sequence also reduced ANG-II-induced [Ca2+]i elevation in the cells. Real-time imaging of cell growth revealed that ANG-II stimulates neonatal GMC proliferation. ANG-II-induced GMC growth was attenuated by EMD 66684, an AGTR1 antagonist; BAPTA, a [Ca2+]i chelator; KN-93, a Ca2+/calmodulin-dependent protein kinase II inhibitor; CDX; and a CSD peptide, but not PD 123319, a selective AGTR2 antagonist. Collectively, our data demonstrate [Ca2+]i-dependent proliferative effect of ANG-II and highlight a critical role for lipid raft microdomains in AGTR1-mediated signal transduction in neonatal GMCs. - Highlights: • AGTR1 is the functional AGTR subtype expressed in neonatal mesangial cells. • Endogenous AGTR1 associates with CAV-1 in neonatal mesangial cells. • Lipid raft disruption attenuates cell surface AGTR1 protein expression. • Lipid raft disruption reduces ANG-II-induced [Ca2+]i elevation in neonatal mesangial cells. • Lipid raft disruption inhibits ANG-II-induced neonatal mesangial cell growth

  13. Lipid rafts are required for signal transduction by angiotensin II receptor type 1 in neonatal glomerular mesangial cells

    Energy Technology Data Exchange (ETDEWEB)

    Adebiyi, Adebowale, E-mail: aadebiyi@uthsc.edu; Soni, Hitesh; John, Theresa A.; Yang, Fen

    2014-05-15

    Angiotensin II (ANG-II) receptors (AGTRs) contribute to renal physiology and pathophysiology, but the underlying mechanisms that regulate AGTR function in glomerular mesangium are poorly understood. Here, we show that AGTR1 is the functional AGTR subtype expressed in neonatal pig glomerular mesangial cells (GMCs). Cyclodextrin (CDX)-mediated cholesterol depletion attenuated cell surface AGTR1 protein expression and ANG-II-induced intracellular Ca{sup 2+} ([Ca{sup 2+}]{sub i}) elevation in the cells. The COOH-terminus of porcine AGTR1 contains a caveolin (CAV)-binding motif. However, neonatal GMCs express CAV-1, but not CAV-2 and CAV-3. Colocalization and in situ proximity ligation assay detected an association between endogenous AGTR1 and CAV-1 in the cells. A synthetic peptide corresponding to the CAV-1 scaffolding domain (CSD) sequence also reduced ANG-II-induced [Ca{sup 2+}]{sub i} elevation in the cells. Real-time imaging of cell growth revealed that ANG-II stimulates neonatal GMC proliferation. ANG-II-induced GMC growth was attenuated by EMD 66684, an AGTR1 antagonist; BAPTA, a [Ca{sup 2+}]{sub i} chelator; KN-93, a Ca{sup 2+}/calmodulin-dependent protein kinase II inhibitor; CDX; and a CSD peptide, but not PD 123319, a selective AGTR2 antagonist. Collectively, our data demonstrate [Ca{sup 2+}]{sub i}-dependent proliferative effect of ANG-II and highlight a critical role for lipid raft microdomains in AGTR1-mediated signal transduction in neonatal GMCs. - Highlights: • AGTR1 is the functional AGTR subtype expressed in neonatal mesangial cells. • Endogenous AGTR1 associates with CAV-1 in neonatal mesangial cells. • Lipid raft disruption attenuates cell surface AGTR1 protein expression. • Lipid raft disruption reduces ANG-II-induced [Ca{sup 2+}]{sub i} elevation in neonatal mesangial cells. • Lipid raft disruption inhibits ANG-II-induced neonatal mesangial cell growth.

  14. Identification of telmisartan as a unique angiotensin II receptor antagonist with selective PPARgamma-modulating activity

    Czech Academy of Sciences Publication Activity Database

    Benson, S. C.; Pershadsingh, H. A.; Ho, C. I.; Chittiboyina, A.; Desai, P.; Pravenec, Michal; Qi, N.; Wang, J.; Avery, M. A.; Kurtz, T. W.

    2004-01-01

    Roč. 43, č. 5 (2004), s. 993-1002. ISSN 0194-911X R&D Projects: GA ČR GA301/01/0278; GA MŠk LN00A079 Grant ostatní: NIH(US) 2R42AR44767-02A2; NIH(US) HL63709; NIH(US) TW01236 Institutional research plan: CEZ:AV0Z5011922 Keywords : receptors * insulin resistance * losartan Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.342, year: 2004

  15. The angiotensin-converting enzyme gene insertion–deletion polymorphism in a white British patient cohort with obstetric cholestasis

    Science.gov (United States)

    Müllenbach, Roman; Tetlow, Natasha; Bennett, Amanda; Pipkin, Fiona Broughton; Morgan, Linda; Williamson, Catherine

    2009-01-01

    The DD genotype of the angiotensin-converting enzyme (ACE) gene is over-represented in Finnish patients with obstetric cholestasis (OC). The purpose of this study was to establish whether this genotype is associated with cholestasis in UK cases. In a retrospective case-control study, we determined the ACE insertion/deletion frequencies in 166 British cases and 100 control women by polymerase chain reaction analysis. No significant difference in allele frequencies was found between these groups, but allele frequencies differed significantly between Finnish and UK OC cases (P = 0.0005). The prevalence of the DD genotype is lower in UK cases than in controls (χ2 [1 d.f.] = 4.32, P = 0.05) and the odds ratio for OC associated with the DD genotypeis 0.54, 95% confidence interval 0.30–0.97. In contrast to Finnish OC cases, the DD genotype of the ACE is not increased in UK cases.

  16. Unique Expression of Angiotensin Type-2 Receptor in Sex-Specific Distribution of Myelinated Ah-Type Baroreceptor Neuron Contributing to Sex-Dimorphic Neurocontrol of Circulation.

    Science.gov (United States)

    Liu, Yang; Zhou, Jia-Ying; Zhou, Yu-Hong; Wu, Di; He, Jian-Li; Han, Li-Min; Liang, Xiao-Bo; Wang, Lu-Qi; Lu, Xiao-Long; Chen, Hanying; Qiao, Guo-Fen; Shou, Weinian; Li, Bai-Yan

    2016-04-01

    This study aims to understand the special expression patterns of angiotensin-II receptor (AT1R and AT2R) in nodose ganglia and nucleus of tractus solitary of baroreflex afferent pathway and their contribution in sex difference of neurocontrol of blood pressure regulation. In this regard, action potentials were recorded in baroreceptor neurons (BRNs) using whole-cell patch techniques; mRNA and protein expression of AT1R and AT2R in nodose ganglia and nucleus of tractus solitary were evaluated using real time-polymerase chain reaction, Western blot, and immunohistochemistry at both tissue and single-cell levels. The in vivo effects of 17β-estradiol on blood pressure and AT2R expression were also tested. The data showed that AT2R, rather than AT1R, expression was higher in female than age-matched male rats. Moreover, AT2R was downregulated in ovariectomized rats, which was restored by the administration of 17β-estradiol. Single-cell real time-polymerase chain reaction data indicated that AT2R was uniquely expressed in Ah-type BRNs. Functional study showed that long-term administration of 17β-estradiol significantly alleviated the blood pressure increase in ovariectomized rats. Electrophysiological recordings showed that angiotensin-II treatment increased the neuroexcitability more in Ah- than C-type BRNs, whereas no such effect was observed in A-types. In addition, angiotensin-II treatment prolonged action potential duration, which was not further changed by iberiotoxin. The density of angiotensin-II-sensitive K(+) currents recorded in Ah-types was equivalent with iberiotoxin-sensitive component. In summary, the unique, sex- and afferent-specific expression of AT2R was identified in Ah-type BRNs, and AT2R-mediated KCa1.1 inhibition in Ah-type BRNs may exert great impacts on baroreflex afferent function and blood pressure regulation in females. PMID:26883269

  17. Angiotensin II type 2 receptor promotes adipocyte differentiation and restores adipocyte size in high-fat/high-fructose diet-induced insulin resistance in rats

    OpenAIRE

    Shum, Michaël; Pinard, Sandra; Guimond, Marie-Odile; Labbé, Sébastien M.; Roberge, Claude; Baillargeon, Jean-Patrice; Langlois, Marie-France; Alterman, Mathias; Wallinder, Charlotta; Hallberg, Anders; Carpentier, André C; Gallo-Payet, Nicole

    2012-01-01

    This study was aimed at establishing whether specific activation of angiotensin II (ANG II) type 2 receptor (AT2R) modulates adipocyte differentiation and function. In primary cultures of subcutaneous (SC) and retroperitoneal (RET) preadipocytes, both AT2R and AT1R were expressed at the mRNA and protein level. Cells were stimulated with ANG II or the AT2R agonist C21/M24, alone or in the presence of the AT1R antagonist losartan or the AT2R antagonist PD123,319. During differentiation, C21/M24...

  18. Distinct properties of telmisartan on agonistic activities for peroxisome proliferator-activated receptor γ among clinically used angiotensin II receptor blockers: drug-target interaction analyses.

    Science.gov (United States)

    Kakuta, Hirotoshi; Kurosaki, Eiji; Niimi, Tatsuya; Gato, Katsuhiko; Kawasaki, Yuko; Suwa, Akira; Honbou, Kazuya; Yamaguchi, Tomohiko; Okumura, Hiroyuki; Sanagi, Masanao; Tomura, Yuichi; Orita, Masaya; Yonemoto, Takako; Masuzaki, Hiroaki

    2014-04-01

    A proportion of angiotensin II type 1 receptor blockers (ARBs) improves glucose dyshomeostasis and insulin resistance in a clinical setting. Of these ARBs, telmisartan has the unique property of being a partial agonist for peroxisome proliferator-activated receptor γ (PPARγ). However, the detailed mechanism of how telmisartan acts on PPARγ and exerts its insulin-sensitizing effect is poorly understood. In this context, we investigated the agonistic activity of a variety of clinically available ARBs on PPARγ using isothermal titration calorimetry (ITC) and surface plasmon resonance (SPR) system. Based on physicochemical data, we then reevaluated the metabolically beneficial effects of telmisartan in cultured murine adipocytes. ITC and SPR assays demonstrated that telmisartan exhibited the highest affinity of the ARBs tested. Distribution coefficient and parallel artificial membrane permeability assays were used to assess lipophilicity and cell permeability, for which telmisartan exhibited the highest levels of both. We next examined the effect of each ARB on insulin-mediated glucose metabolism in 3T3-L1 preadipocytes. To investigate the impact on adipogenesis, 3T3-L1 preadipocytes were differentiated with each ARB in addition to standard inducers of differentiation for adipogenesis. Telmisartan dose-dependently facilitated adipogenesis and markedly augmented the mRNA expression of adipocyte fatty acid-binding protein (aP2), accompanied by an increase in the uptake of 2-deoxyglucose and protein expression of glucose transporter 4 (GLUT4). In contrast, other ARBs showed only marginal effects in these experiments. In accordance with its highest affinity of binding for PPARγ as well as the highest cell permeability, telmisartan superbly activates PPARγ among the ARBs tested, thereby providing a fresh avenue for treating hypertensive patients with metabolic derangement. PMID:24424487

  19. Leptin_receptor - Wikipedia, the free encyclopedia [Gene Wiki

    Lifescience Database Archive (English)

    Full Text Available Leptin receptor - Wikipedia, the free encyclopediaLeptin receptorFrom Wikipedia, the free encycl ... nce variation at the human leptin receptor gene in lean ... and obese Pima Indians". Hum. Mol. Genet. 6 (5): 6 ...

  20. Pharmacological interventions into the renin-angiotensin system with ACE inhibitors and angiotensin II receptor antagonists: effects beyond blood pressure lowering.

    Science.gov (United States)

    Düsing, Rainer

    2016-06-01

    Hypertension is recognized as an important risk factor for cardiovascular morbidity and mortality. Lowering of blood pressure has been shown to minimize the risk of cardiovascular events, with the majority of antihypertensives demonstrating a similar ability to reduce coronary events and stroke for a given reduction in blood pressure. Agents that modify the activity of the renin-angiotensin system (RAS) have been proposed to exhibit additional effects that might go beyond simple blood pressure lowering. The RAS is a crucial system that regulates extracellular fluid volume and blood pressure. Proposed potential benefits of RAS blockade that go beyond blood pressure lowering include a reduction in platelet aggregation and thrombosis, blunting of cardiac and vascular remodeling, favorable metabolic effects and reno- and cerebro-protection. However, factors such as treatment adherence, duration of action of antihypertensive agents and differences in effects on central versus brachial blood pressure may also result in apparent differences in efficacy of different antihypertensives. The aim of this review article is to examine the available data from clinical studies of antihypertensive drugs for evidence of effects that might legitimately be claimed to go beyond simple blood pressure lowering. PMID:27122491

  1. The angiotensin II-AT1 receptor stimulates reactive oxygen species within the cell nucleus

    Energy Technology Data Exchange (ETDEWEB)

    Pendergrass, Karl D.; Gwathmey, TanYa M. [The Hypertension and Vascular Research Center, Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157 (United States); Michalek, Ryan D.; Grayson, Jason M. [Department of Microbiology and Immunology, Wake Forest University School of Medicine, Winston-Salem, NC 27157 (United States); Chappell, Mark C., E-mail: mchappel@wfubmc.edu [The Hypertension and Vascular Research Center, Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157 (United States)

    2009-06-26

    We and others have reported significant expression of the Ang II Type 1 receptor (AT1R) on renal nuclei; thus, the present study assessed the functional pathways and distribution of the intracellular AT1R on isolated nuclei. Ang II (1 nM) stimulated DCF fluorescence, an intranuclear indicator of reactive oxygen species (ROS), while the AT1R antagonist losartan or the NADPH oxidase (NOX) inhibitor DPI abolished the increase in ROS. Dual labeling of nuclei with antibodies against nucleoporin 62 (Nup62) and AT1R or the NADPH oxidase isoform NOX4 revealed complete overlap of the Nup62 and AT1R (99%) by flow cytometry, while NOX4 was present on 65% of nuclei. Treatment of nuclei with a PKC agonist increased ROS while the PKC inhibitor GF109203X or PI3 kinase inhibitor LY294002 abolished Ang II stimulation of ROS. We conclude that the Ang II-AT1R-PKC axis may directly influence nuclear function within the kidney through a redox sensitive pathway.

  2. Transcriptional up-regulation in expression of 5-hydroxytryptamine2A and transcriptional down-regulation of angiotensin II type 1 receptors during organ culture of rat mesenteric artery

    DEFF Research Database (Denmark)

    Luo, Guogang; Xu, Cang-Bao; Cao, Yong-Xiao;

    2004-01-01

    receptors (5-HT(2A)) and angiotensin II type 1 receptors (AT(1)) demonstrated that the contractions occurred via 5-HT(2A) and AT(1) receptors, respectively. Real-time PCR revealed that the 5-HT(2A) receptor mRNA was up-regulated in parallel with the contractile response while there was a down-regulation of...... AT(1) receptor mRNA. Transcriptional inhibitor actinomycin D and specific protein kinase C inhibitor Ro31-8220 demonstrated that it was a transcriptional mechanism with involvement of protein kinase C that regulated the enhanced expression of 5-HT(2A) receptors in the mesenteric artery....

  3. Insertion/Insertion Genotype of Angiotensin I-Converting-Enzyme Gene Predicts Risk of Myocardial Infarction in North East India.

    Science.gov (United States)

    Baruah, Sukanya; Chaliha, Mriganka S; Borah, Prasanta K; Rajkakati, Rashmi; Borua, Prodeep K; Mahanta, Jagadish

    2016-04-01

    Myocardial infarction (MI) is common in India and the disease occurs at a relatively younger age. We wanted to look for association of Angiotensin I-converting enzyme (ACE) gene with MI in North East India. We also wanted to examine possible environmental interaction of ACE gene with established cardiovascular risk factors in causation of MI. In the study carried out in Assam Medical College, 200 consecutive confirmed cases of MI were recruited. Equal numbers of age- and sex-matched control subjects from hospital workers and patients attending the hospital for diseases unrelated to cardiovascular disease were enrolled. Structured questionnaires were used to note demographic and clinical factors. Cardiovascular risk factors were determined from history, physical examination and biochemical investigations. ACE insertion/deletion (I/D) polymorphism was determined by PCR method. Interaction of ACE gene with other risk factors was noted. The study identified ACE II genotype (odds ratio = 3.02; 95% CI 1.40-6.51), smoking, hypertension, diabetes and serum triglyceride > 150 mg/dl as independent risk factors for MI. ACE II genotype showed greater risk in non-smokers, non-hypertensives, non-diabetics and in subjects with LDL-C < 130 mg/dl. Low HDL cholesterol enhanced the genetic risk. Subjects with ACE II genotype have an independent risk of developing MI, specially in low cardiovascular risk subjects. PMID:26687160

  4. Discovery of a series of imidazo[4,5-b]pyridines with dual activity at angiotensin II type 1 receptor and peroxisome proliferator-activated receptor-γ.

    Science.gov (United States)

    Casimiro-Garcia, Agustin; Filzen, Gary F; Flynn, Declan; Bigge, Christopher F; Chen, Jing; Davis, Jo Ann; Dudley, Danette A; Edmunds, Jeremy J; Esmaeil, Nadia; Geyer, Andrew; Heemstra, Ronald J; Jalaie, Mehran; Ohren, Jeffrey F; Ostroski, Robert; Ellis, Teresa; Schaum, Robert P; Stoner, Chad

    2011-06-23

    Mining of an in-house collection of angiotensin II type 1 receptor antagonists to identify compounds with activity at the peroxisome proliferator-activated receptor-γ (PPARγ) revealed a new series of imidazo[4,5-b]pyridines 2 possessing activity at these two receptors. Early availability of the crystal structure of the lead compound 2a bound to the ligand binding domain of human PPARγ confirmed the mode of interaction of this scaffold to the nuclear receptor and assisted in the optimization of PPARγ activity. Among the new compounds, (S)-3-(5-(2-(1H-tetrazol-5-yl)phenyl)-2,3-dihydro-1H-inden-1-yl)-2-ethyl-5-isobutyl-7-methyl-3H-imidazo[4,5-b]pyridine (2l) was identified as a potent angiotensin II type I receptor blocker (IC(50) = 1.6 nM) with partial PPARγ agonism (EC(50) = 212 nM, 31% max) and oral bioavailability in rat. The dual pharmacology of 2l was demonstrated in animal models of hypertension (SHR) and insulin resistance (ZDF rat). In the SHR, 2l was highly efficacious in lowering blood pressure, while robust lowering of glucose and triglycerides was observed in the male ZDF rat. PMID:21557540

  5. Discovery of a Series of Imidazo[4,5-b]pyridines with Dual Activity at Angiotensin II Type 1 Receptor and Peroxisome Proliferator-Activated Receptor-[gamma

    Energy Technology Data Exchange (ETDEWEB)

    Casimiro-Garcia, Agustin; Filzen, Gary F.; Flynn, Declan; Bigge, Christopher F.; Chen, Jing; Davis, Jo Ann; Dudley, Danette A.; Edmunds, Jeremy J.; Esmaeil, Nadia; Geyer, Andrew; Heemstra, Ronald J.; Jalaie, Mehran; Ohren, Jeffrey F.; Ostroski, Robert; Ellis, Teresa; Schaum, Robert P.; Stoner, Chad (Pfizer)

    2013-03-07

    Mining of an in-house collection of angiotensin II type 1 receptor antagonists to identify compounds with activity at the peroxisome proliferator-activated receptor-{gamma} (PPAR{gamma}) revealed a new series of imidazo[4,5-b]pyridines 2 possessing activity at these two receptors. Early availability of the crystal structure of the lead compound 2a bound to the ligand binding domain of human PPAR{gamma} confirmed the mode of interaction of this scaffold to the nuclear receptor and assisted in the optimization of PPAR{gamma} activity. Among the new compounds, (S)-3-(5-(2-(1H-tetrazol-5-yl)phenyl)-2,3-dihydro-1H-inden-1-yl)-2-ethyl-5-isobutyl-7-methyl-3H-imidazo[4,5-b]pyridine (2l) was identified as a potent angiotensin II type I receptor blocker (IC{sub 50} = 1.6 nM) with partial PPAR{gamma} agonism (EC{sub 50} = 212 nM, 31% max) and oral bioavailability in rat. The dual pharmacology of 2l was demonstrated in animal models of hypertension (SHR) and insulin resistance (ZDF rat). In the SHR, 2l was highly efficacious in lowering blood pressure, while robust lowering of glucose and triglycerides was observed in the male ZDF rat.

  6. Effect of angiotensin converting enzyme gene I/D polymorphism in patients with metabolic syndrome in North Indian population

    Institute of Scientific and Technical Information of China (English)

    Gaurav Mittal; Vibhanshu Gupta; Shahzad F Haque; Anwer S Khan

    2011-01-01

    Background Numerous studies have investigated the effect of angiotensin converting enzyme (ACE) gene I/D polymorphism and various cardiovascular risk factors in different populations with varied results. Currently, the association of ACE gene polymorphism with metabolic syndrome has not been studied in North Indians. While studies assessing the effect with polymorphism on each of the components of metabolic syndrome separately are present, data regarding the metabolic syndrome per se are sparse. The present study evaluated the effect of ACE gene I/D polymorphism in patients with metabolic syndrome in North Indian population at a tertiary care centre.Methods Fifty subjects, with thirty cases of metabolic syndrome (NCEP/ATP Ⅲ guidelines, 2004) and twenty age and gender matched healthy controls were chosen. Detailed history was reviewed and clinical examination of the subjects was carried out. Relevant investigations including blood glucose (fasting and post prandial), blood urea, serum creatinine and serum lipids were done. DNA of cases and controls was analysed for I/D polymorphism using polymerase chain reaction.Results D/D genotype was more frequent in patients with metabolic syndrome as compared with healthy controls (P<0.05). Systolic blood pressure (SBP) and diastolic blood pressure (DBP) was significantly higher in the D/D genotype than I/D and I/I genotypes (P <0.05). Our study also showed positive association between obesity, fasting blood glucose and ACE gene polymorphism while no association was found with triglycerides and high density lipoprotein cholesterol.The I/I group was significantly associated with waist circumference and fasting blood glucose (P <0.05).Conclusion Our study clearly showed that metabolic syndrome was associated with ACE gene polymorphism.However due to less number of subjects in the study further studies are needed to corroborate our results.

  7. Variations in angiotensin-converting enzyme gene insertion/deletion polymorphism in Indian populations of different ethnic origins

    Indian Academy of Sciences (India)

    M A Qadar Pasha; Amjad P Khan; Ratan Kumar; Rekh B Ram; Surinder K Grover; Kaushal K Srivastava; William Selvamurthy; Samir K Brahmachari

    2002-02-01

    The pattern of angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism in the Indian population is poorly known. In order to determine the status of the polymorphism, young unrelated male army recruits were screened. The population had cultural and linguistic differences and lived in an environment that varied significantly from one region to another. Analysis of the genotype, showed higher frequency of the insertion allele in four of the five groups i.e. I allele frequency was significantly higher ( < 0.05) in Dogras, Assamese and Kumaonese. The deletion allele frequency was comparatively higher in the fifth group that belonged to Punjab. A correlation was observed between the genotype and enzyme activity. Involvement of a single D allele in the genotype enhanced the activity up to 37.56 ± 3.13%. The results suggested ethnic heterogeneity with a significant gene cline with higher insertion allele frequency. Such population-based data on various polymorphisms can ultimately be exploited in pharmacogenomics.

  8. [The role of angiotensin-converting enzyme gene I/D polymorphism in development of metabolic disorders in patients with cardiovascular pathology].

    Science.gov (United States)

    Vynohradova, S V

    2005-01-01

    The role of angiotensin-converting enzyme (ACE) gene I/D polymorphism in development of cardiovascular pathology (CVP), metabolic syndrom and insulin-independent diabet associated with such metabolic disorders as glucose intolerance and hyperglicemia, intolerance to insulin and hyperinsulinemia, dyslipiproteinemia (DLP) and obesity is discussed. Most of authors consider D-allel and DD genotype to be assosiated with development of DLP and such CVP as ishemic heart disease and myocardial infarction. PMID:16018179

  9. Association of Angiotensin-Converting Enzyme (ACE Gene Polymorphism with Inflammation and Cellular Cytotoxicity in Vitiligo Patients.

    Directory of Open Access Journals (Sweden)

    Laila Rashed

    Full Text Available Vitiligo is a disorder with profound heterogeneity in its aetio-pathophysiology. Angiotensin converting enzyme (ACE plays an important role in the physiology of the vasculature, blood pressure and inflammation. An insertion/deletion (I/D polymorphism of the ACE gene was reported be associated with the development of vitiligo.Our aim was to evaluate the ACE I/D polymorphism in vitiligo patients and controls. Our second aim was to find a possible association between ACE gene polymorphism and inflammatory mediators (as interleukin (IL-6 and/or cellular cytotoxicity induced by serum nitrite (as a breakdown product of the cytotoxic nitric oxide in vitiligo patients.This case-control study included 74 vitiligo patients and 75 apparently healthy controls. The distribution of ACE gene I/D genotype was investigated using PCR. Serum ACE, IL-6 and nitrite were measured by colorimetric method, ELISA and Griess assay respectively.The ACE allele frequency was significantly different between vitiligo patients and healthy controls (P = 0.026. However there was no significant difference between the ACE genotyping frequency in both groups (P = 0.115. There were statistically significant higher VIDA score (P = 0.007, and serum IL-6 (P < 0.001 in patients with the DD genotype when compared to other genotypes. Serum nitrite in patients with the DD genotype was significantly higher (P = 0.007 when compared to patients with II genotype. Serum levels of ACE, IL-6 and nitrite in vitiligo patients were statistically significantly higher than those in controls.As a conclusion, ACE gene polymorphism might grant susceptibility to develop vitiligo. Serum IL-6 and nitrite levels might have an important role in the pathogenesis of vitiligo. Targeting these two factors might have an implication in the treatment of some resistant cases.

  10. The discovery of new potent non-peptide Angiotensin II AT1 receptor blockers: A concise synthesis, molecular docking studies and biological evaluation of N-substituted 5-butylimidazole derivatives

    Czech Academy of Sciences Publication Activity Database

    Agelis, G.; Resvani, A.; Durdagi, S.; Spyridaki, K.; Tůmová, Tereza; Slaninová, Jiřina; Giannopoulos, P.; Vlahakos, D.; Liapakis, G.; Mavromoustakos, T.; Matsoukas, J.

    2012-01-01

    Roč. 55, Sep (2012), s. 358-374. ISSN 0223-5234 Institutional research plan: CEZ:AV0Z40550506 Keywords : synthesis * angiotensin II receptor blockers * N-substituted 5-butylimidazole derivatives * antihypertensive activity * molecular docking Subject RIV: CC - Organic Chemistry Impact factor: 3.499, year: 2012

  11. Survival and Predictive Factors of Lethality in Hemodyalisis: D/I Polymorphism of The Angiotensin I-Converting Enzyme and of the Angiotensinogen M235T Genes

    International Nuclear Information System (INIS)

    End-stage kidney disease patients continue to have markedly increased cardiovascular disease morbidity and mortality. Analysis of genetic factors connected with the renin-angiotensin system that influences the survival of the patients with end-stage kidney disease supports the ongoing search for improved outcomes. To assess survival and its association with the polymorphism of renin-angiotensin system genes: angiotensin I-converting enzyme insertion/deletion and angiotensinogen M235T in patients undergoing hemodialysis. Our study was designed to examine the role of renin-angiotensin system genes. It was an observational study. We analyzed 473 chronic hemodialysis patients in four dialysis units in the state of Rio de Janeiro. Survival rates were calculated by the Kaplan-Meier method and the differences between the curves were evaluated by Tarone-Ware, Peto-Prentice, and log rank tests. We also used logistic regression analysis and the multinomial model. A p value ≤ 0.05 was considered to be statistically significant. The local medical ethics committee gave their approval to this study. The mean age of patients was 45.8 years old. The overall survival rate was 48% at 11 years. The major causes of death were cardiovascular diseases (34%) and infections (15%). Logistic regression analysis found statistical significance for the following variables: age (p = 0.000038), TT angiotensinogen (p = 0.08261), and family income greater than five times the minimum wage (p = 0.03089), the latter being a protective factor. The survival of hemodialysis patients is likely to be influenced by the TT of the angiotensinogen M235T gene

  12. Survival and Predictive Factors of Lethality in Hemodyalisis: D/I Polymorphism of The Angiotensin I-Converting Enzyme and of the Angiotensinogen M235T Genes

    Directory of Open Access Journals (Sweden)

    Mauro Alves

    2014-09-01

    Full Text Available Background: End-stage kidney disease patients continue to have markedly increased cardiovascular disease morbidity and mortality. Analysis of genetic factors connected with the renin-angiotensin system that influences the survival of the patients with end-stage kidney disease supports the ongoing search for improved outcomes. Objective: To assess survival and its association with the polymorphism of renin-angiotensin system genes: angiotensin I-converting enzyme insertion/deletion and angiotensinogen M235T in patients undergoing hemodialysis. Methods: Our study was designed to examine the role of renin-angiotensin system genes. It was an observational study. We analyzed 473 chronic hemodialysis patients in four dialysis units in the state of Rio de Janeiro. Survival rates were calculated by the Kaplan-Meier method and the differences between the curves were evaluated by Tarone-Ware, Peto-Prentice, and log rank tests. We also used logistic regression analysis and the multinomial model. A p value ≤ 0.05 was considered to be statistically significant. The local medical ethics committee gave their approval to this study. Results: The mean age of patients was 45.8 years old. The overall survival rate was 48% at 11 years. The major causes of death were cardiovascular diseases (34% and infections (15%. Logistic regression analysis found statistical significance for the following variables: age (p = 0.000038, TT angiotensinogen (p = 0.08261, and family income greater than five times the minimum wage (p = 0.03089, the latter being a protective factor. Conclusions: The survival of hemodialysis patients is likely to be influenced by the TT of the angiotensinogen M235T gene.

  13. Survival and Predictive Factors of Lethality in Hemodyalisis: D/I Polymorphism of The Angiotensin I-Converting Enzyme and of the Angiotensinogen M235T Genes

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Mauro, E-mail: malves@cardiol.br; Silva, Nelson Albuquerque de Souza e; Salis, Lucia Helena Alvares; Pereira, Basilio de Bragança; Godoy, Paulo Henrique; Nascimento, Emília Matos do [Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Oliveira, Jose Mario Franco [Universidade Federal Fluminense, Niterói, RJ (Brazil)

    2014-09-15

    End-stage kidney disease patients continue to have markedly increased cardiovascular disease morbidity and mortality. Analysis of genetic factors connected with the renin-angiotensin system that influences the survival of the patients with end-stage kidney disease supports the ongoing search for improved outcomes. To assess survival and its association with the polymorphism of renin-angiotensin system genes: angiotensin I-converting enzyme insertion/deletion and angiotensinogen M235T in patients undergoing hemodialysis. Our study was designed to examine the role of renin-angiotensin system genes. It was an observational study. We analyzed 473 chronic hemodialysis patients in four dialysis units in the state of Rio de Janeiro. Survival rates were calculated by the Kaplan-Meier method and the differences between the curves were evaluated by Tarone-Ware, Peto-Prentice, and log rank tests. We also used logistic regression analysis and the multinomial model. A p value ≤ 0.05 was considered to be statistically significant. The local medical ethics committee gave their approval to this study. The mean age of patients was 45.8 years old. The overall survival rate was 48% at 11 years. The major causes of death were cardiovascular diseases (34%) and infections (15%). Logistic regression analysis found statistical significance for the following variables: age (p = 0.000038), TT angiotensinogen (p = 0.08261), and family income greater than five times the minimum wage (p = 0.03089), the latter being a protective factor. The survival of hemodialysis patients is likely to be influenced by the TT of the angiotensinogen M235T gene.

  14. Effect of angiotensin I-converting enzyme and α-actinin-3 gene polymorphisms on sport performance.

    Science.gov (United States)

    Gunel, Tuba; Gumusoglu, Ece; Hosseini, Mohammad Kazem; Yilmazyildirim, Eda; Dolekcap, Ismail; Aydinli, Kilic

    2014-04-01

    Genetic polymorphism is considered to be associated with human physical performance. The angiotensin I-converting enzyme insertion/deletion (ACE I/D) and the α-actinin-3 gene (ACTN3) R577X polymorphisms have been widely investigated for such associations, and functional ACE I/D and ACTN3 R577X polymorphisms have been associated with sprinter performance. The aim of this study was to determine the effect of these polymorphisms on sport performance among 37 elite athletes and 37 healthy controls. The ACE II genotype was identified in 32.43% of the control group and 8.11% of elite athletes, the DD genotype in 37.84% of the control group and 51.35% of the elite athletes, and the ID genotype in 29.73% of the control group and 40.54% of the elite athletes. With regard to the ACTN3 gene, the XX genotype, which confers an advantage for endurance activities, was identified in 10.81% of the control group and 35.14% of the elite athletes. The XX genotype was observed more frequently than the RR genotype (advantageous for sprinting), which was identified in 2.70% of the control group and 10.81% of elite athletes. The RX genotype (observed in 86.48% of the control group and in 54.05% of the elite athletes) was the most common genotype of the individuals in the present study. The study showed that ACTN3 and ACE gene polymorphisms have an effect on muscle power; however, larger studies are required. PMID:24566537

  15. Polymorphisms of angiotensin-converting enzyme 2 gene confer a risk to lone atrial fibrillation in Chinese male patients

    Institute of Scientific and Technical Information of China (English)

    WANG Shu-xia; TAO Tao; FU Zhi-qing; XIE Xiang-zhu; WANG Hao; WANG Yu-tang

    2013-01-01

    Background Growing epidemiologic evidence has indicated that genetics can predispose individuals to the occurrence of lone atrial fibrillation (AF).The angiotensin-converting enzyme 2 (ACE2) gene has been established to be associated with hypertension and left ventricular hypertrophy.The objective of our study was to investigate the association of ACE2 gene polymorphisms with lone AF.Methods A total of 265 consecutive lone AF patients and 289 healthy controls were successfully investigated.The polymorphisms rs2106809 and rs2285666 were genotyped by polymerase chain reaction (PCR) and direct sequencing.A Logistic regression model was used to determine the odds ratio (OR) and 95% confidence intervals (CI) of variations of ACE2 for lone AF.Results The T allele of rs2106809 conferred an increased risk for lone AF (OR 1.24,95% CI 1.01-1.52,P=0.03) in males after adjustment for conventional risk factors.SNP at rs2285666 in males was not significantly different between AF patients and controls.No association was found between the two polymorphisms in the female population with lone AF.After (36.3±4.5) months of follow-up,the end point data were obtained:death (cardiac and noncardiac),ischemic stroke,and heart failure.In the male subgroup,the associations between rs2106809 T male carriers and combined end points including ischemic stroke,heart failure,and death in our study were of significance (OR 3.6,95% CI 1.0-13.1,P=0.04).Conclusions The results indicate that polymorphism at ACE2 gene is associated with male lone AF in a Chinese Han population.Lone AF males who carry the rs2106809 T allele are associated with adverse cardiac events.

  16. Gender Difference in Renal Blood Flow Response to Angiotensin II Administration after Ischemia/Reperfusion in Rats: The Role of AT2 Receptor

    Science.gov (United States)

    Maleki, Maryam

    2016-01-01

    Background. Renal ischemia/reperfusion (I/R) is one of the major causes of kidney failure, and it may interact with renin angiotensin system while angiotensin II (Ang II) type 2 receptor (AT2R) expression is gender dependent. We examined the role of AT2R blockade on vascular response to Ang II after I/R in rats. Methods. Male and female rats were subjected to 30 min renal ischemia followed by reperfusion. Two groups of rats received either vehicle or AT2R antagonist, PD123319. Mean arterial pressure (MAP), and renal blood flow (RBF) responses were assessed during graded Ang II (100, 300, and 1000 ng/kg/min, i.v.) infusion at controlled renal perfusion pressure (RPP). Results. Vehicle or antagonist did not alter MAP, RPP, and RBF levels significantly; however, 30 min after reperfusion, RBF decreased insignificantly in female treated with PD123319 (P = 0.07). Ang II reduced RBF and increased renal vascular resistance (RVR) in a dose-related fashion (Pdose < 0.0001), and PD123319 intensified the reduction of RBF response in female (Pgroup < 0.005), but not in male rats. Conclusion. The impact of the AT2R on vascular responses to Ang II in renal I/R injury appears to be sexually dimorphic. PD123319 infusion promotes these hemodynamic responses in female more than in male rats. PMID:27034657

  17. High-Dose Estradiol-Replacement Therapy Enhances the Renal Vascular Response to Angiotensin II via an AT2-Receptor Dependent Mechanism

    Science.gov (United States)

    Safari, Tahereh; Nematbakhsh, Mehdi; Evans, Roger G.; Denton, Kate M.

    2015-01-01

    Physiological levels of estrogen appear to enhance angiotensin type 2 receptor- (AT2R-) mediated vasodilatation. However, the effects of supraphysiological levels of estrogen, analogous to those achieved with high-dose estrogen replacement therapy in postmenopausal women, remain unknown. Therefore, we pretreated ovariectomized rats with a relatively high dose of estrogen (0.5 mg/kg/week) for two weeks. Subsequently, renal hemodynamic responses to intravenous angiotensin II (Ang II, 30–300 ng/kg/min) were tested under anesthesia, while renal perfusion pressure was held constant. The role of AT2R was examined by pretreating groups of rats with PD123319 or its vehicle. Renal blood flow (RBF) decreased in a dose-related manner in response to Ang II. Responses to Ang II were enhanced by pretreatment with estradiol. For example, at 300 ng kg−1 min−1, Ang II reduced RBF by 45.7 ± 1.9% in estradiol-treated rats but only by 27.3 ± 5.1% in vehicle-treated rats. Pretreatment with PD123319 blunted the response of RBF to Ang II in estradiol-treated rats, so that reductions in RBF were similar to those in rats not treated with estradiol. We conclude that supraphysiological levels of estrogen promote AT2R-mediated renal vasoconstriction. This mechanism could potentially contribute to the increased risk of cardiovascular disease associated with hormone replacement therapy using high-dose estrogen. PMID:26681937

  18. The impact of dose of the angiotensin-receptor blocker valsartan on the post-myocardial infarction ventricular remodeling: study protocol for a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Cho Young-Rak

    2011-11-01

    Full Text Available Abstract Background Angiotensin-converting enzyme inhibitors and the angiotensin-receptor blocker valsartan ameliorate ventricular remodeling after myocardial infarction (MI. Based on previous clinical trials, a maximum clinical dose is recommended in practical guidelines. Yet, has not been clearly demonstrated whether the recommended dose is more efficacious compared to the lower dose that is commonly used in clinical practice. Method/Design Valsartan in post-MI remodeling (VALID is a randomized, open-label, single-blinded multicenter study designed to compare the efficacy of different clinical dose of valsartan on the post-MI ventricular remodeling. This study also aims to assess neurohormone change and clinical parameters of patients during the post-infarct period. A total of 1116 patients with left ventricular dysfunction following the first episode of acute ST-elevation MI are to be enrolled and randomized to a maximal tolerable dose (up to 320 mg/day or usual dose (80 mg/day of valsartan for 12 months in 2:1 ratio. Echocardiographic analysis for quantifying post-MI ventricular remodeling is to be conducted in central core laboratory. Clinical assessment and laboratory test are performed at fixed times. Discussion VALID is a multicenter collaborative study to evaluate the impact of dose of valsartan on the post-MI ventricular remodeling. The results of the study provide information about optimal dosing of the drug in the management of patients after MI. The results will be available by 2012. Trial registration NCT01340326

  19. Angiotensin converting enzyme inhibition does not affect the response to exogenous angiotensin II in the human forearm.

    OpenAIRE

    Lyons, D.; D. Stewart; Webster, J; Benjamin, N

    1994-01-01

    Suppression of endogenous levels of angiotensin II by angiotensin converting enzyme inhibition, may result in up-regulation of vascular AT1 receptors. We have evaluated the effects of orally administered enalapril on angiotensin II induced vasoconstriction in the human forearm. Subjects received in random order, enalapril (20 mg) or matched placebo daily for 2 weeks. Forearm blood flow response to increasing doses of angiotensin II was measured using venous occlusion plethysmography at the be...

  20. FGF receptor genes and breast cancer susceptibility

    DEFF Research Database (Denmark)

    Agarwal, D; Pineda, S; Michailidou, K;

    2014-01-01

    Background:Breast cancer is one of the most common malignancies in women. Genome-wide association studies have identified FGFR2 as a breast cancer susceptibility gene. Common variation in other fibroblast growth factor (FGF) receptors might also modify risk. We tested this hypothesis by studying......, 12 893 (6269 cases and 6624 controls) of Asian and 2048 (1116 cases and 932 controls) of African ancestry. Associations with risk of breast cancer, overall and by disease sub-type, were assessed using unconditional logistic regression.Results:Little evidence of association with breast cancer risk...... that common variants in the other FGF receptors are not associated with risk of breast cancer to the degree observed for FGFR2....

  1. A cleavable signal peptide enhances cell surface delivery and heterodimerization of Cerulean-tagged angiotensin II AT1 and bradykinin B2 receptor

    International Nuclear Information System (INIS)

    Highlights: → A new FRET-based method detects AT1/B2 receptor heterodimerization. → First time application of AT1-Cerulean as a FRET donor. → Method relies on signal peptide-enhanced cell surface delivery of AT1-Cerulean. → A high FRET efficiency revealed efficient heterodimerization of AT1/B2R proteins. → AT1/B2R heterodimers were functionally coupled to desensitization mechanisms. -- Abstract: Heterodimerization of the angiotensin II AT1 receptor with the receptor for the vasodepressor bradykinin, B2R, is known to sensitize the AT1-stimulated response of hypertensive individuals in vivo. To analyze features of that prototypic receptor heterodimer in vitro, we established a new method that uses fluorescence resonance energy transfer (FRET) and applies for the first time AT1-Cerulean as a FRET donor. The Cerulean variant of the green fluorescent protein as donor fluorophore was fused to the C-terminus of AT1, and the enhanced yellow fluorescent protein (EYFP) as acceptor fluorophore was fused to B2R. In contrast to AT1-EGFP, the AT1-Cerulean fusion protein was retained intracellularly. To facilitate cell surface delivery of AT1-Cerulean, a cleavable signal sequence was fused to the receptor's amino terminus. The plasma membrane-localized AT1-Cerulean resembled the native AT1 receptor regarding ligand binding and receptor activation. A high FRET efficiency of 24.7% between membrane-localized AT1-Cerulean and B2R-EYFP was observed with intact, non-stimulated cells. Confocal FRET microscopy further revealed that the AT1/B2 receptor heterodimer was functionally coupled to receptor desensitization mechanisms because activation of the AT1-Cerulean/B2R-EYFP heterodimer with a single agonist triggered the co-internalization of AT1/B2R. Receptor co-internalization was sensitive to inhibition of G protein-coupled receptor kinases, GRKs, as evidenced by a GRK-specific peptide inhibitor. In agreement with efficient AT1/B2R heterodimerization, confocal FRET imaging of

  2. A cleavable signal peptide enhances cell surface delivery and heterodimerization of Cerulean-tagged angiotensin II AT1 and bradykinin B2 receptor

    Energy Technology Data Exchange (ETDEWEB)

    Quitterer, Ursula, E-mail: ursula.quitterer@pharma.ethz.ch [Molecular Pharmacology Unit, Swiss Federal Institute of Technology and University of Zurich, Zurich (Switzerland); Pohl, Armin; Langer, Andreas; Koller, Samuel; AbdAlla, Said [Molecular Pharmacology Unit, Swiss Federal Institute of Technology and University of Zurich, Zurich (Switzerland)

    2011-06-10

    Highlights: {yields} A new FRET-based method detects AT1/B2 receptor heterodimerization. {yields} First time application of AT1-Cerulean as a FRET donor. {yields} Method relies on signal peptide-enhanced cell surface delivery of AT1-Cerulean. {yields} A high FRET efficiency revealed efficient heterodimerization of AT1/B2R proteins. {yields} AT1/B2R heterodimers were functionally coupled to desensitization mechanisms. -- Abstract: Heterodimerization of the angiotensin II AT1 receptor with the receptor for the vasodepressor bradykinin, B2R, is known to sensitize the AT1-stimulated response of hypertensive individuals in vivo. To analyze features of that prototypic receptor heterodimer in vitro, we established a new method that uses fluorescence resonance energy transfer (FRET) and applies for the first time AT1-Cerulean as a FRET donor. The Cerulean variant of the green fluorescent protein as donor fluorophore was fused to the C-terminus of AT1, and the enhanced yellow fluorescent protein (EYFP) as acceptor fluorophore was fused to B2R. In contrast to AT1-EGFP, the AT1-Cerulean fusion protein was retained intracellularly. To facilitate cell surface delivery of AT1-Cerulean, a cleavable signal sequence was fused to the receptor's amino terminus. The plasma membrane-localized AT1-Cerulean resembled the native AT1 receptor regarding ligand binding and receptor activation. A high FRET efficiency of 24.7% between membrane-localized AT1-Cerulean and B2R-EYFP was observed with intact, non-stimulated cells. Confocal FRET microscopy further revealed that the AT1/B2 receptor heterodimer was functionally coupled to receptor desensitization mechanisms because activation of the AT1-Cerulean/B2R-EYFP heterodimer with a single agonist triggered the co-internalization of AT1/B2R. Receptor co-internalization was sensitive to inhibition of G protein-coupled receptor kinases, GRKs, as evidenced by a GRK-specific peptide inhibitor. In agreement with efficient AT1/B2R

  3. Common Promoter Elements in Odorant and Vomeronasal Receptor Genes

    OpenAIRE

    Jussara S Michaloski; Galante, Pedro A. F.; Nagai, Maíra H.; Lucia Armelin-Correa; Ming-Shan Chien; Hiroaki Matsunami; Bettina Malnic

    2011-01-01

    In mammals, odorants and pheromones are detected by hundreds of odorant receptors (ORs) and vomeronasal receptors (V1Rs and V2Rs) expressed by sensory neurons that are respectively located in the main olfactory epithelium and in the vomeronasal organ. Even though these two olfactory systems are functionally and anatomically separate, their sensory neurons show a common mechanism of receptor gene regulation: each neuron expresses a single receptor gene from a single allele. The mechanisms unde...

  4. The angiotensin-receptor blocker candesartan for treatment of acute stroke (SCAST): a randomised, placebo-controlled, double-blind trial

    DEFF Research Database (Denmark)

    Sandset, Else Charlotte; Bath, Philip M W; Boysen, Gudrun;

    2011-01-01

    BACKGROUND: Raised blood pressure is common in acute stroke, and is associated with an increased risk of poor outcomes. We aimed to examine whether careful blood-pressure lowering treatment with the angiotensin-receptor blocker candesartan is beneficial in patients with acute stroke and raised...... blood pressure. METHODS: Participants in this randomised, placebo-controlled, double-blind trial were recruited from 146 centres in nine north European countries. Patients older than 18 years with acute stroke (ischaemic or haemorrhagic) and systolic blood pressure of 140 mm Hg or higher were included...... within 30 h of symptom onset. Patients were randomly allocated to candesartan or placebo (1:1) for 7 days, with doses increasing from 4 mg on day 1 to 16 mg on days 3 to 7. Randomisation was stratified by centre, with blocks of six packs of candesartan or placebo. Patients and investigators were masked...

  5. Insight into the structural requirement of substituted quinazolinone biphenyl acylsulfonamides derivatives as Angiotensin II AT1 receptor antagonist: 2D and 3D QSAR approach

    Directory of Open Access Journals (Sweden)

    Mukesh C. Sharma

    2014-01-01

    Full Text Available A series of 19 molecules substituted quinazolinone biphenyl acylsulfonamides derivatives displaying variable inhibition of Angiotensin II receptor AT1 activity were selected to develop models for establishing 2D and 3D QSAR. The compounds in the selected series were characterized by spatial, molecular and electro topological descriptors using QSAR module of Molecular Design Suite (VLife MDS™ 3.5. The best 2D QSAR model was selected, having correlation coefficient r2 (0.8056 and cross validated squared correlation coefficient q2 (0.6742 with external predictive ability of pred_r2 0.7583 coefficient of correlation of predicted data set (pred_r2se 0.2165. The results obtained from QSAR studies could be used in designing better Ang II activity among the congeners in future. The optimum QSAR model showed that the parameters SsssCHE index, SddCE-index, T_2_Cl_4, and SssNHE-index contributed in the model. 3D QSAR analysis by kNN-molecular field analysis approach developed based on principles of the k-nearest neighbor method combined with Genetic algorithms, stepwise forward variable selection approach; a leave-one-out cross-validated correlation coefficient (q2 of 0.6516 and a non-cross-validated correlation coefficient (r2 of 0.8316 and pred_r2 0.6954 were obtained. Contour maps using this approach showed that steric, electrostatic, and hydrophobic field effects dominantly determine binding affinities. The information rendered by 3D QSAR models may lead to a better understanding of structural requirements of Angiotensin II receptor and can help in the design of novel potent antihypertensive molecules.

  6. Brain penetration of telmisartan, a unique centrally acting angiotensin II type 1 receptor blocker, studied by PET in conscious rhesus macaques

    International Nuclear Information System (INIS)

    Introduction: Telmisartan is a widely used, long-acting antihypertensive agent. Known to be a selective angiotensin II type 1 (AT1) receptor (AT1R) blocker (ARB), telmisartan acts as a partial agonist of peroxisome proliferator-activated receptor-gamma (PPAR-γ) and inhibits centrally mediated effects of angiotensin II in rats following peripheral administration, although the brain penetration of telmisartan remains unclear. We investigated the brain concentration and localization of telmisartan using 11 C-labeled telmisartan and positron emission tomography (PET) in conscious rhesus macaques. Methods: Three male rhesus macaques were bolus intravenously administered [11 C]telmisartan either alone or as a mixture with unlabeled telmisartan (1 mg/kg). Dynamic PET images were acquired for 95 min following administration. Blood samples were collected for the analysis of plasma concentration and metabolites, and brain and plasma concentrations were calculated from detected radioactivity using the specific activity of the administered drug preparation, in which whole blood radioactivity was used for the correction of intravascular blood radioactivity in brain. Results: Telmisartan penetrated into the brain little but enough to block AT1R and showed a consistently increasing brain/plasma ratio within the PET scanning period, suggesting slow clearance of the compound from the brain compared to the plasma clearance. Brain/plasma ratios at 30, 60, and 90 min were 0.06, 0.13, and 0.18, respectively. No marked localization according to the AT1R distribution was noted over the entire brain, even on tracer alone dosing. Conclusions: Telmisartan penetrated into the brain enough to block AT1R and showed a slow clearance from the brain in conscious rhesus macaques, supporting the long-acting and central responses of telmisartan as a unique property among ARBs.

  7. O polimorfismo A1166C do receptor tipo 1 da angiotensina II no infarto agudo do miocárdio The A1166C polymorphism of the angiotensin II type-1 receptor in acute myocardial infarction

    Directory of Open Access Journals (Sweden)

    Messias Antônio de Araújo

    2004-11-01

    Full Text Available RESUMO OBJETIVO:Avaliar a associação do polimorfismo A1166C do gene do receptor AT1 da angiotensina II (AT1R com o infarto agudo do miocárdio e a severidade da doença arterial coronariana. MÉTODOS: Estudo prospectivo, transversal de 110 pacientes com infarto agudo do miocárdio submetidos à angiografia coronariana com lesão significante (> 50% avaliada por três critérios de severidade: número de vasos lesados, morfologia da placa aterosclerótica e escore de risco coronariano. Sem lesões coronarianas 104 indivíduos controles. O polimorfismo A1166C do gene do AT1R foi determinado pela reação em cadeia da polimerase no DNA dos leucócitos do sangue periférico. Os fatores de risco coronariano clássicos foram analisados em todos os indivíduos. RESULTADOS: Na estratificação dos genótipos em relação aos fatores de risco apenas o tabagismo teve predominância nos heterozigotos AC (p = 0,02. A freqüência dos genótipos nos pacientes infartados foi de AA = 54,5%; AC = 35,5% e CC = 10%, sendo similar e não significativa em relação aos controles (p = 0,83. Não houve aumento do risco de infarto agudo do miocárdio nas comparações dos genótipos CC vs AA (OR = 1,35; IC-95% = 0,50 - 3,59, AC vs AA (OR = 1,03; IC-95% = 0,58 - 1,84 e AA+AC vs AA (OR = 1,33; IC-95% = 0,51 - 3,45. Nenhum dos critérios de severidade teve associação significativa com os genótipos. CONCLUSÃO: Os nossos resultados indicam não haver associação do polimorfismo A1166C do AT1R com o infarto agudo do miocárdio e nem com a severidade da doença arterial coronariana segundo nossos resultados.OBJECTIVE: To assess the association of the A1166C polymorphism of the angiotensin II type-1 receptor (AT1R gene with acute myocardial infarction and also with the severity of coronary artery disease. METHODS: A prospective, cross-sectional study was carried out with 110 patients with acute myocardial infarction, who, on coronary angiography, had significant

  8. Expression of the Components of the Renin–Angiotensin System in Venous Malformation

    OpenAIRE

    Siljee, Sam; Keane, Emily; Marsh, Reginald; Brasch, Helen D.; Tan, Swee T.; Itinteang, Tinte

    2016-01-01

    Background Venous malformation (VM) is the most common form of vascular malformation, consisting of a network of thin-walled ectatic venous channels with deficient or absent media. This study investigated the expression of the components of the renin–angiotensin system (RAS), namely, (pro)renin receptor (PRR), angiotensin-converting enzyme (ACE), angiotensin II receptor 1 (ATIIR1), and angiotensin II receptor 2 (AIITR2) in subcutaneous (SC) and intramuscular (IM) VM. Materials and methods SC ...

  9. Toll-like receptor 4 upregulation by angiotensin II contributes to hypertension and vascular dysfunction through reactive oxygen species production.

    Directory of Open Access Journals (Sweden)

    Priscila R De Batista

    Full Text Available Hypertension is considered as a low-grade inflammatory disease, with adaptive immunity being an important mediator of this pathology. TLR4 may have a role in the development of several cardiovascular diseases; however, little is known about its participation in hypertension. We aimed to investigate whether TLR4 activation due to increased activity of the renin-angiotensin system (RAS contributes to hypertension and its associated endothelial dysfunction. For this, we used aortic segments from Wistar rats treated with a non-specific IgG (1 µg/day and SHRs treated with losartan (15 mg/kg·day, the non-specific IgG or the neutralizing antibody anti-TLR4 (1 µg/day, as well as cultured vascular smooth muscle cells (VSMC from Wistar and SHRs. TLR4 mRNA levels were greater in the VSMC and aortas from SHRs compared with Wistar rats; losartan treatment reduced those levels in the SHRs. Treatment of the SHRs with the anti-TLR4 antibody: 1 reduced the increased blood pressure, heart rate and phenylephrine-induced contraction while it improved the impaired acetylcholine-induced relaxation; 2 increased the potentiation of phenylephrine contraction after endothelium removal; and 3 abolished the inhibitory effects of tiron, apocynin and catalase on the phenylephrine-induced response as well as its enhancing effect of acetylcholine-induced relaxation. In SHR VSMCs, angiotensin II increased TLR4 mRNA levels, and losartan reduced that increase. CLI-095, a TLR4 inhibitor, mitigated the increases in NAD(PH oxidase activity, superoxide anion production, migration and proliferation that were induced by angiotensin II. In conclusion, TLR4 pathway activation due to increased RAS activity is involved in hypertension, and by inducing oxidative stress, this pathway contributes to the endothelial dysfunction associated with this pathology. These results suggest that TLR4 and innate immunity may play a role in hypertension and its associated end-organ damage.

  10. Identification of Significant Association and Gene-Gene Interaction of GABA Receptor Subunit Genes in Autism

    OpenAIRE

    Ma, D Q; Whitehead, P. L.; Menold, M M; Martin, E. R.; Ashley-Koch, A. E.; Mei, H; Ritchie, M. D.; Delong, G R; Abramson, R.K.; Wright, H. H.; Cuccaro, M. L.; Hussman, J. P.; Gilbert, J.R.; Pericak-Vance, M A

    2005-01-01

    Autism is a common neurodevelopmental disorder with a significant genetic component. Existing research suggests that multiple genes contribute to autism and that epigenetic effects or gene-gene interactions are likely contributors to autism risk. However, these effects have not yet been identified. Gamma-aminobutyric acid (GABA), the primary inhibitory neurotransmitter in the adult brain, has been implicated in autism etiology. Fourteen known autosomal GABA receptor subunit genes were studied...

  11. A Meta-analysis on the correlation between the polymorphism of angiotensin converting enzyme gene and hypertrophic cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Ling CHEN

    2014-01-01

    Full Text Available Objective To systematically investigate the correlation between the polymorphism of angiotensin converting enzyme (ACE gene I/D and hypertrophic cardiomyopathy. Methods The databases, such as PubMed, Embase, OVID, Web of Science, Cochrane library, CNKI, WanFang Data and VIP, were searched to collect the studies on the correlation between ACE I/D polymorphism and hypertrophic cardiomyopathy susceptibility. Studies that met the inclusion criteria were Meta-analyzed using Stata 11.0 software. Results Fifteen articles were collected including 1114 cases and 1648 controls. The Meta-analysis indicated that there was significant correlation between the 4 models of ACE I/D polymorphism and hypertrophic cardiomyopathy susceptibility [D vs I: OR=1.49, 95%CI (1.20, 1.84; DD vs (ID+II: OR=1.56, 95%CI (1.17, 2.08; (DD+ID vs II: OR=1.76, 95%CI (1.30, 2.38; DD vs II: OR=2.20, 95%CI (1.44, 3.37]. In subgroup analysis, the significant difference existed in Asian population, but no significance was found in European population (P<0.05. Conclusions There is a positive correlation between hypertrophic cardiomyopathy and ACE I/D polymorphism in population, and D allele and DD genotype are likely to be the risk factors of hypertrophic cardiomyopathy. But such correlation does not exist in European population. DOI: 10.11855/j.issn.0577-7402.2013.12.07

  12. Gene Expression Profiling Following Maternal Deprivation: Involvement of the Brain Renin-Angiotensin System

    OpenAIRE

    Liebl, Claudia; Panhuysen, Markus; Pütz, Benno; Trümbach, Dietrich; Wurst, Wolfgang; Deussing, Jan M.; Müller, Marianne B.; Schmidt, Mathias V.

    2009-01-01

    The postnatal development of the mouse is characterized by a stress hypo-responsive period (SHRP), where basal corticosterone levels are low and responsiveness to mild stressors is reduced. Maternal separation is able to disrupt the SHRP and is widely used to model early trauma. In this study we aimed at identifying of brain systems involved in acute and possible long-term effects of maternal separation. We conducted a microarray-based gene expression analysis in the hypothalamic paraventricu...

  13. Gene expression profiling following maternal deprivation: Involvement of the brain renin-angiotensin system

    OpenAIRE

    Wolfgang Wurst; Deussing, Jan M.

    2009-01-01

    The postnatal development of the mouse is characterized by a stress hyporesponsive period (SHRP), where basal corticosterone levels are low and responsiveness to mild stressors is reduced. Maternal separation is able to disrupt the SHRP and is widely used to model early trauma. In this study we aimed at identifying of brain systems involved in acute and possible long-term effects of maternal separation. We conducted a microarray-based gene expression analysis in the hypothalamic paraventricul...

  14. Bradykinin potentiation by angiotensin-(1-7) and ACE inhibitors correlates with ACE C- and N-domain blockade

    NARCIS (Netherlands)

    B. Tom (Beril); R. de Vries (René); P.R. Saxena (Pramod Ranjan); A.H.J. Danser (Jan)

    2001-01-01

    textabstractACE inhibitors block B(2) receptor desensitization, thereby potentiating bradykinin beyond blocking its hydrolysis. Angiotensin (Ang)-(1-7) also acts as an ACE inhibitor and, in addition, may stimulate bradykinin release via angiotensin II type 2 receptors.

  15. What is a preferred angiotensin II receptor blocker-based combination therapy for blood pressure control in hypertensive patients with diabetic and non-diabetic renal impairment?

    Directory of Open Access Journals (Sweden)

    Mallat Samir G

    2012-04-01

    Full Text Available Abstract Hypertension has a major associated risk for organ damage and mortality, which is further heightened in patients with prior cardiovascular (CV events, comorbid diabetes mellitus, microalbuminuria and renal impairment. Given that most patients with hypertension require at least two antihypertensives to achieve blood pressure (BP goals, identifying the most appropriate combination regimen based on individual risk factors and comorbidities is important for risk management. Single-pill combinations (SPCs containing two or more antihypertensive agents with complementary mechanisms of action offer potential advantages over free-drug combinations, including simplification of treatment regimens, convenience and reduced costs. The improved adherence and convenience resulting from SPC use is recognised in updated hypertension guidelines. Despite a wide choice of SPCs for hypertension treatment, clinical evidence from direct head-to-head comparisons to guide selection for individual patients is lacking. However, in patients with evidence of renal disease or at greater risk of developing renal disease, such as those with diabetes mellitus, microalbuminura and high-normal BP or overt hypertension, guidelines recommend renin-angiotensin system (RAS blocker-based combination therapy due to superior renoprotective effects compared with other antihypertensive classes. Furthermore, RAS inhibitors attenuate the oedema and renal hyperfiltration associated with calcium channel blocker (CCB monotherapy, making them a good choice for combination therapy. The occurrence of angiotensin-converting enzyme (ACE inhibitor-induced cough supports the use of angiotensin II receptor blockers (ARBs for RAS blockade rather than ACE inhibitors. In this regard, ARB-based SPCs are available in combination with the diuretic, hydrochlorothiazide (HCTZ or the calcium CCB, amlodipine. Telmisartan, a long-acting ARB with preferential pharmacodynamic profile compared with several

  16. Androgen receptor gene polymorphism in zebra species

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    Hideyuki Ito

    2015-09-01

    Full Text Available Androgen receptor genes (AR have been found to have associations with reproductive development, behavioral traits, and disorders in humans. However, the influence of similar genetic effects on the behavior of other animals is scarce. We examined the loci AR glutamine repeat (ARQ in 44 Grevy's zebras, 23 plains zebras, and three mountain zebras, and compared them with those of domesticated horses. We observed polymorphism among zebra species and between zebra and horse. As androgens such as testosterone influence aggressiveness, AR polymorphism among equid species may be associated with differences in levels of aggression and tameness. Our findings indicate that it would be useful to conduct further studies focusing on the potential association between AR and personality traits, and to understand domestication of equid species.

  17. Exercise training attenuates age-dependent elevation of angiotensin II type 1 receptor and Nox2 signaling in the rat heart.

    Science.gov (United States)

    Lee, Yang; Kwak, Hyo-Bum; Hord, Jeff; Kim, Jong-Hee; Lawler, John M

    2015-10-01

    Fibrosis of the aging heart impedes cardiac function and increases the risk of arrhythmias and heart disease. Previously, we demonstrated that exercise-induced reduction of collagen I in the aging heart was linked to a suppression of oxidative stress and transforming growth factor-beta (TGF-ß). The renin-angiotensin II system (RAS) increases oxidative stress via NADPH oxidase-2 (Nox2) and thus elevates TGF-ß and collagen accumulation. Therefore, we tested the hypothesis that exercise training would alleviate age-related upregulation of the angiotensin II receptor I (AT1R) and NADPH oxidase-2 (Nox2), concomitant with suppression of TGF-β and fibrosis. Young (3 months, n=20) and old (31 months, n=20) Fischer 344 ×B rown Norway F1 (FBNF1) hybrid rats were assigned into sedentary and exercise groups, with exercise training rats training on a treadmill 45 min/day, 5 days/week for the next 12 weeks. Exercise training mitigated age-related upregulation of AT1R, Nox2 activity, and Nox2 subunits gp91phox and p47phox. Exercise training also attenuated TGF-ß positive staining and downstream effectors of fibrosis in the aging heart: connective tissue growth factor, phosphorylation of Smad2 at Ser423, myofibroblast proliferation, and collagen I-positive staining. Our results are consistent with the hypothesis that exercise training protects against age-dependent cardiac fibrosis by suppressing AT1R and Nox2 as part of a RAS-Nox2-TGF-β pathway. PMID:26239262

  18. Angiotensinreceptor blocker provides pancreatic β-cell protection independent of blood pressure lowering in diabetic db/db mice

    Institute of Scientific and Technical Information of China (English)

    Jia-qing SHAO; Noseki IWASHITA; Hong DU; Yang-tian WANG; Yan-yan WANG; Ming ZHAO; Jian WANG; Hirotaka WATADA; Ryuzo KAWAMORI

    2007-01-01

    Aim: Several epidemiological studies have suggested that treatment with angiotensin Ⅱ type 1 receptor blocker provided a risk reduction of developing type 2 diabetes. The aim of this study was to investigate whether and how chronic candesartan treatment can attenuate the deleterious influence of the hyperactive local intra-islet renin-angiotensin system in the diabetes state. Methods: Eight-week-old db/db mice were randomized to candesartan 1 mg/kg, candesartan 10mg/kg, manidipine 10 mg/kg, or placebo via gavage for 6 weeks. Their age-matched nondiabetic littermates db/m mice were treated with placebo and acted as nondia-betic controls. After 6 weeks' treatment, an intraperitoneal glucose tolerance test, immunohistochemical staining of oxidative stress markers, insulin, CD31, azan staining and an electron microscopy observation were performed. Results: Chronic candesartan treatment provided an improvement of glucose tolerance, and greatly rescued islet β-cell mass. Candesartan treatment also notably decreased staining intensity of oxidative stress markers, as well as attenuating intra-islet fibrosis and improving blood supply in the islet. In the electron microscopy observation, candesartan-treated animals exhibited improved granulation and less remarkable endoplasmic reticulum and Golgi bodies; furthermore, candesartan treatment greatly relieved the swelling of mitochondria to nearly normal. Both the benefits of reducing oxidative stress and ultra structure protection were in a dose-dependent and blood pressure-independent manner. Conclusion: After diabetes was initiated, candesartan treatment could not reverse the state of diabetes, but it effectively improved glucose tolerance and protected β-cell function by attenuating oxidative stress, islet fibrosis, sparsity of blood supply and ultrastructure disruption in a dose-dependent and blood pressure-independent manner.

  19. Risk conferred by FokI polymorphism of vitamin D receptor (VDR gene for essential hypertension

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    N Swapna

    2011-01-01

    Full Text Available Background : The vitamin D receptor (VDR gene serves as a good candidate gene for susceptibility to several diseases. The gene has a critical role in regulating the renin-angiotensin system (RAS influencing the regulation of blood pressure. Hence determining the association of VDR polymorphisms with essential hypertension is expected to help in the evaluation of risk for the condition. Aim : The aim of this study was to evaluate association between VDR Fok I polymorphism and genetic susceptibility to essential hypertension. Materials and Methods : Two hundred and eighty clinically diagnosed hypertensive patients and 200 normotensive healthy controls were analyzed for Fok I (T/C [rs2228570] polymorphism by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP analysis. Genotype distribution and allele frequencies in patients and controls, and odds ratios (ORs were calculated to predict the risk for developing hypertension by the individuals of different genotypes. Results : The genotype distribution and allele frequencies of Fok I (T/C [rs2228570] VDR polymorphism differed significantly between patients and controls (χ2 of 18.0; 2 degrees of freedom; P = 0.000. FF genotype and allele F were at significantly greater risk for developing hypertension and the risk was elevated for both the sexes, cases with positive family history and habit of smoking. Conclusions : Our data suggest that VDR gene Fok I polymorphism is associated with the risk of developing essential hypertension

  20. Single nucleotide polymorphisms in the apolipoprotein B and low density lipoprotein receptor genes affect response to antihypertensive treatment

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    Kahan Thomas

    2004-09-01

    Full Text Available Abstract Background Dyslipidemia has been associated with hypertension. The present study explored if polymorphisms in genes encoding proteins in lipid metabolism could be used as predictors for the individual response to antihypertensive treatment. Methods Ten single nucleotide polymorphisms (SNP in genes related to lipid metabolism were analysed by a microarray based minisequencing system in DNA samples from ninety-seven hypertensive subjects randomised to treatment with either 150 mg of the angiotensin II type 1 receptor blocker irbesartan or 50 mg of the β1-adrenergic receptor blocker atenolol for twelve weeks. Results The reduction in blood pressure was similar in both treatment groups. The SNP C711T in the apolipoprotein B gene was associated with the blood pressure response to irbesartan with an average reduction of 19 mmHg in the individuals carrying the C-allele, but not to atenolol. The C16730T polymorphism in the low density lipoprotein receptor gene predicted the change in systolic blood pressure in the atenolol group with an average reduction of 14 mmHg in the individuals carrying the C-allele. Conclusions Polymorphisms in genes encoding proteins in the lipid metabolism are associated with the response to antihypertensive treatment in a drug specific pattern. These results highlight the potential use of pharmacogenetics as a guide for individualised antihypertensive treatment, and also the role of lipids in blood pressure control.

  1. Genetic and Functional Analysis of Androgen Receptor Gene Mutations

    OpenAIRE

    Brüggenwirth, Hennie

    1998-01-01

    textabstractNuclear hormone receptors (NHRs) are intermediary factors through which extracellular signals regulate expression of genes that are involved in homeostasis, development, and differentiation (Beato et al. '995, Mangelsdorf and Evans 1995). These receptors are characterized by a modular structure, with domains involved in transcription activation, DNA binding. hormone binding, and dimerization. The nuclear receptor super-family comprises three subfamilies of receptors, which might h...

  2. The Prognostic Role of Angiotensin II Type 1 Receptor Autoantibody in Non-Gravid Hypertension and Pre-eclampsia: A Meta-analysis and Our Studies.

    Science.gov (United States)

    Lei, Jinghui; Li, Yafeng; Zhang, Suli; Wu, Ye; Wang, Pengli; Liu, Huirong

    2016-04-01

    Angiotensin II type 1 receptor autoantibody (AT1-AA) is found in patients with non-gravid hypertension or pre-eclampsia, but the relationship is uncertain.The aim of the present study was to assess the association between AT1-AA and high blood pressure using meta-analysis, and to evaluate the prognosis value of AT1-AA for hypertensive diseases.Literature search from PubMed, Embase, and Cochrane databases were conducted using keywords "hypertension" or "pre-eclampsia," "angiotensin II receptor type 1 autoantibody," and its aliases from April 1999 to December 2015.Studies evaluating the association between AT1-AA and non-gravid hypertension or pre-eclampsia were included in this analysis. The quality of the eligible studies was assessed based on the Newcastle-Ottawa Scale with some modifications.Two researchers then independently reviewed all included studies and extracted all relevant data. Association between AT1-AA and hypertension was tested with pooled odds ratios (ORs) and 95% confidence intervals (CIs). Finally, we evaluated whether AT1-AA predicted the prognosis of hypertension by using a summary receiver-operating characteristic (ROC) curve and sensitivity analysis.Ten studies were finally included in this meta-analysis. AT1-AA showed more significant association with pre-eclampsia than that with non-gravid hypertension (pooled OR 32.84, 95% CI 17.19-62.74; and pooled OR 4.18, 95% CI 2.20-7.98, respectively). Heterogeneity among studies was also detected probably due to different hypertensive subtypes and AT1-AA measuring methods. Area under summary ROC curve (AUC) of pre-eclampsia was 0.92 (sensitivity 0.76; specificity 0.86). Area under the ROC curve of overall hypertensive diseases or non-gravid hypertension was lower than that of pre-eclampsia (0.86 and 0.72, respectively) with lower sensitivities (0.46 and 0.26, respectively).The major limitation of this analysis was the publication bias due to lack of unpublished data and the language limitation during

  3. Recent advances in angiotensin II signaling

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    R.M. Touyz

    2002-09-01

    Full Text Available Angiotensin II (Ang II* is a multifunctional hormone that influences the function of cardiovascular cells through a complex series of intracellular signaling events initiated by the interaction of Ang II with AT1 and AT2 receptors. AT1 receptor activation leads to cell growth, vascular contraction, inflammatory responses and salt and water retention, whereas AT2 receptors induce apoptosis, vasodilation and natriuresis. These effects are mediated via complex, interacting signaling pathways involving stimulation of PLC and Ca2+ mobilization; activation of PLD, PLA2, PKC, MAP kinases and NAD(PH oxidase, and stimulation of gene transcription. In addition, Ang II activates many intracellular tyrosine kinases that play a role in growth signaling and inflammation, such as Src, Pyk2, p130Cas, FAK and JAK/STAT. These events may be direct or indirect via transactivation of tyrosine kinase receptors, including PDGFR, EGFR and IGFR. Ang II induces a multitude of actions in various tissues, and the signaling events following occupancy and activation of Ang receptors are tightly controlled and extremely complex. Alterations of these highly regulated signaling pathways may be pivotal in structural and functional abnormalities that underlie pathological processes in cardiovascular diseases such as cardiac hypertrophy, hypertension and atherosclerosis.

  4. Angiotensin II induces the production of MMP-3 and MMP-13 through the MAPK signaling pathways via the AT(1) receptor in osteoblasts.

    Science.gov (United States)

    Nakai, Kumiko; Kawato, Takayuki; Morita, Toyoko; Iinuma, Toshimitsu; Kamio, Noriaki; Zhao, Ning; Maeno, Masao

    2013-04-01

    Angiotensin II (Ang II) plays an important role in the maintenance of bone mass and integrity by activation of the mitogen-activated protein kinases (MAPKs) and by modulation of balance between resorption by osteoclasts and formation by osteoblasts. However, the role of Ang II in the turnover of extracellular matrix (ECM) in osteoid by osteoblasts remains unclear. Therefore, we examined the effect of Ang II on the expression of matrix metalloproteinases (MMPs), plasminogen activators (PAs), and their inhibitors [i.e., tissue inhibitors of metalloproteinases (TIMPs) and PA inhibitor-1 (PAI-1)] using osteoblastic ROS17/2.8 cells. Treatment with Ang II strikingly increased the expressions of MMP-3 and -13 and promoted cell proliferation associated with reduced alkaline phosphatase activity as well as enhanced phosphorylated expression of extracellular signal-regulated kinase (ERK)1/2, p38 MAPK, and stress-activated protein kinases/c-jun N-terminal kinases (SAPK/JNK) in ROS17/2.8 cells. However, Ang II had no effect on the expression of MMP-2, -9, -14, urokinase-type PA, tissue-type PA, TIMP-1, -2, -3, and PAI-1 in cells. Losartan (AT1 receptor blocker) blocked Ang II-induced expression of MMP-3 and -13, whereas PD123319 (AT2 receptor blocker) did not completely block these responses. Losartan also blocked the Ang II-induced phosphorylation of ERK1/2, p38 MAPK, and SAPK/JNK. MAPK kinase 1/2 inhibitor PD98059 and JNK inhibitor SP600125 suppressed Ang II-induced expression of MMP-3 and -13. These results suggested that Ang II stimulated the degradation process that occurs during ECM turnover in osteoid by increasing the production of MMP-3 and -13 through MAPK signaling pathways via the AT1 receptor in osteoblasts. Furthermore, our findings suggest that Ang II does not influence the plasminogen/plasmin pathway in osteoblasts. PMID:23277113

  5. Alternative splicing of human and mouse NPFF2 receptor genes: Implications to receptor expression.

    Science.gov (United States)

    Ankö, Minna-Liisa; Ostergård, Maria; Lintunen, Minnamaija; Panula, Pertti

    2006-12-22

    Alternative splicing has an important role in the tissue-specific regulation of gene expression. Here we report that similar to the human NPFF2 receptor, the mouse NPFF2 receptor is alternatively spliced. In human the presence of three alternatively spliced receptor variants were verified, whereas two NPFF2 receptor variants were identified in mouse. The alternative splicing affected the 5' untranslated region of the mouse receptor and the variants in mouse were differently distributed. The mouse NPFF system may also have species-specific features since the NPFF2 receptor mRNA expression differs from that reported for rat. PMID:17157836

  6. Amlodipine versus angiotensin II receptor blocker; control of blood pressure evaluation trial in diabetics (ADVANCED-J

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    Ikeda Shunya

    2006-10-01

    Full Text Available Abstract Background The coexistence of type 2 diabetes mellitus and hypertension increases the risk of cardiovascular diseases. The U.K. Prospective Diabetes Study has shown that blood pressure control as well as blood glucose control is efficient for prevention of complications in hypertensive patients with diabetes mellitus. However, some reports have shown that it is difficult to control the blood pressure and the concomitant use of a plurality of drugs is needed in hypertensive patients with diabetes mellitus. In recent years renin-angiotensin system depressants are increasingly used for the blood pressure control in diabetic patients. Particularly in Japan, angiotensin II (A II antagonists are increasingly used. However, there is no definite evidence of the point of which is efficient for the control, the increase in dose of A II antagonist or the concomitant use of another drug, in hypertensive patients whose blood pressure levels are inadequately controlled with A II antagonist. Methods/Design Hypertensive patients of age 20 years or over with type 2 diabetes mellitus who have been treated by the single use of AII antagonist at usual doses for at least 8 weeks or patients who have been treated by the concomitant use of AII antagonist and an antihypertensive drug other than calcium channel blockers and ACE inhibitors at usual doses for at least 8 weeks are included. Discussion We designed a multi-center, prospective, randomized, open label, blinded-endpoint trial, ADVANCED-J, to compare the increases in dose of A II antagonist and the concomitant use of a Ca-channel blocker (amlodipine and A II antagonist in hypertensive patients with diabetes mellitus, whose blood pressure levels were inadequately controlled with A II antagonist. This study is different from the usual previous studies in that home blood pressures are assessed as indicators of evaluation of blood pressure. The ADVANCED-J study may have much influence on selection of

  7. Dopamine receptor-mediated regulation of neuronal "clock" gene expression.

    Science.gov (United States)

    Imbesi, M; Yildiz, S; Dirim Arslan, A; Sharma, R; Manev, H; Uz, T

    2009-01-23

    Using a transgenic mice model (i.e. "clock" knockouts), clock transcription factors have been suggested as critical regulators of dopaminergic behaviors induced by drugs of abuse. Moreover, it has been shown that systemic administration of psychostimulants, such as cocaine and methamphetamine regulates the striatal expression of clock genes. However, it is not known whether dopamine receptors mediate these regulatory effects of psychostimulants at the cellular level. Primary striatal neurons in culture express dopamine receptors as well as clock genes and have been successfully used in studying dopamine receptor functioning. Therefore, we investigated the role of dopamine receptors on neuronal clock gene expression in this model using specific receptor agonists. We found an inhibitory effect on the expression of mClock and mPer1 genes with the D2-class (i.e. D2/D3) receptor agonist quinpirole. We also found a generalized stimulatory effect on the expression of clock genes mPer1, mClock, mNPAS2 (neuronal PAS domain protein 2), and mBmal1 with the D1-class (i.e. D1) receptor agonist SKF38393. Further, we tested whether systemic administration of dopamine receptor agonists causes similar changes in striatal clock gene expression in vivo. We found quinpirole-induced alterations in mPER1 protein levels in the mouse striatum (i.e. rhythm shift). Collectively, our results indicate that the dopamine receptor system may mediate psychostimulant-induced changes in clock gene expression. Using striatal neurons in culture as a model, further research is needed to better understand how dopamine signaling modulates the expression dynamics of clock genes (i.e. intracellular signaling pathways) and thereby influences neuronal gene expression, neuronal transmission, and brain functioning. PMID:19017537

  8. Hemodynamic effect of angiotensin II receptor blockade in postmenopausal women on a high-sodium diet: A double-blind, randomized, placebo-controlled study

    Science.gov (United States)

    Pechère-Bertschi, Antoinette; Maillard, Marc; Bischof, Paul; Fathi, Marc; Burnier, Michel

    2008-01-01

    Background: Hypertension becomes increasingly prevalent after menopause. Postmenopausal women are more responsive to salt than premenopausal women, and they have been reported to develop marked renal vasoconstriction on a high-sodium diet. Objective: The aim of this study was to assess whether angiotensin II receptor blockade can restore a normal pattern of renal response to salt in postmenopausal women on a high-sodium diet. We also assessed segmental renal sodium handling in that population. Methods: Normotensive and hypertensive postmenopausal women not receiving hormone replacement therapy were enrolled in this prospective, double-blind, placebo-controlled, crossover study. They were assigned to receive irbesartan 150 mg or placebo for 6 weeks; the sequence in which they received irbesartan or placebo was randomized. During the last week of treatment, they received a high-sodium diet (250 mmol/d). Ambulatory blood pressure (ABP), glomerular filtration rate (GFR), and effective renal plasma flow (ERPF) were measured using sinistrin and para-amino-hippurate clearances. Renal sodium handling was assessed by measuring endogenous lithium clearance on day 7 of the high-salt diet. Results: Nineteen women (mean age, 54.7 years; range, 43–72 years; 7 normotensive subjects [mean age, 53.4 years; range, 47–61 years] and 12 hypertensive subjects [mean age, 55.4 years; range, 43–72 years]) were included in the study. When the data for all 19 subjects were pooled, ABP was significantly lower with irbesartan than placebo both during the day (120 [3]/79 [2] vs 127 [3]/85 [2] mm Hg; both, P < 0.01) and at night (systolic BP, 107 [4] vs 111 [4] mm Hg [P < 0.01] and diastolic BP, 71 [2] vs 75 [2] mm Hg [P < 0.05]). Compared with placebo, irbesartan was not associated with a significant change in GFR in either the normotensive or the hypertensive women. When the data for all 19 subjects were pooled, irbesartan was associated with a significant increase in ERPF compared with

  9. Effects of angiotensinreceptor antagonist on expression of collagen Ⅲ, collagen Ⅴ, and transforming growth factor β1 in the airway walls of sensitized rats

    Institute of Scientific and Technical Information of China (English)

    杜永成; 许建英; 张韶君

    2004-01-01

    Background Repeated attacks of bronchial asthma lead to different degrees of airway remodeling, the mechanism of which is not yet clear. Some evidences indicate that it is related to the excessive expression of some growth promotion factors. Angiotensin Ⅱ is a polypeptide that may be involved in airway remodeling. To evaluate its role in airway remodeling in asthma, we observed the effects of an angiotensin Ⅱ type 1 receptor antagonist (valsartan) on the expression of collagen Ⅲ, collagen Ⅴ, and transforming growth factor β1 (TGF-β1) mRNA and protein in the airway walls of sensitized rats.Methods Forty Wistar rats were randomly divided into 5 groups: control group, sensitized group, and valsartan groups 1, 2, and 3. The rats in the sensitized group and in valsartan groups 1, 2, and 3 were sensitized and challenged with ovalbumin. Rats in control group were sensitized and challenged with 0.9% NaCl. Rats from valsartan groups 1, 2, and 3 were drenched with valsartan (10 μg, 20 μg, or 30 μg, respectively) at the time of the ovalbumin challenges. The expression of collagen Ⅲ, collagen Ⅴ, and TGF-β1 protein were detected using immunohistochemical method in combination with image analysis methods. The expression of TGF-β1 mRNA was detected by in situ hybridization. Results The expression in the airways of collagen Ⅲ and collagen Ⅴ was significantly higher in rats from the sensitized group (7.73±0.81, 1.34±0.28) and from valsartan groups 1, 2, and 3 (5.73±0.64, 1.13±0.15; 4.96±0.51, 0.98±0.08; 4.43±0.35, 0.93±0.06, respectively) than those in the control group (2.65±0.38, 0.67±0.08, P<0.05). In addition, collagen levels were significantly lower in valsartan groups 1, 2, and 3 than those from the sensitized group (P<0.05). The expression of TGF-β1 mRNA and protein in the airways was significantly higher in rats from the sensitized group (20.49%±3.46%, 29.73%±3.25%) and from valsartan groups 1, 2, and 3 (16.47%±1.94%, 19.41%±1.87%; 14

  10. Update on the olfactory receptor (OR gene superfamily

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    Olender Tsviya

    2008-09-01

    Full Text Available Abstract The olfactory receptor gene (OR superfamily is the largest in the human genome. The superfamily contains 390 putatively functional genes and 465 pseudogenes arranged into 18 gene families and 300 subfamilies. Even members within the same subfamily are often located on different chromosomes. OR genes are located on all autosomes except chromosome 20, plus the X chromosome but not the Y chromosome. The gene:pseudogene ratio is lowest in human, higher in chimpanzee and highest in rat and mouse -- most likely reflecting the greater need of olfaction for survival in the rodent than in the human. The OR genes undergo allelic exclusion, each sensory neurone expressing usually only one odourant receptor allele; the mechanism by which this phenomenon is regulated is not yet understood. The nomenclature system (based on evolutionary divergence of genes into families and subfamilies of the OR gene superfamily has been designed similarly to that originally used for the CYP gene superfamily.

  11. Inhibitory Effect of the Punica granatum Fruit Extract on Angiotensin-II Type I Receptor and Thromboxane B2 in Endothelial Cells Induced by Plasma from Preeclamptic Patients.

    Science.gov (United States)

    Kusumawati, Widya; Keman, Kusnarman; Soeharto, Setyawati

    2016-01-01

    This study aims to evaluate whether the Punica granatum fruit extract modulates the Angiotensin-II Type I receptor (AT1-R) and thromboxane B2 level in endothelial cells induced by plasma from preeclamptic patients. Endothelial cells were obtained from human umbilical vascular endothelial cells. At confluence, endothelial cells were divided into five groups, which included endothelial cells exposed to 2% plasma from normal pregnancy (NP), endothelial cells exposed to 2% plasma from preeclamptic patients (PP), and endothelial cells exposed to PP in the presence of ethanolic extract of Punica granatum (PP + PG) at the following three doses: 14; 28; and 56 ppm. The expression of AT1-R was observed by immunohistochemistry technique, and thromboxane B2 level was done by immunoassay technique. Plasma from PP significantly increased AT1-R expression and thromboxane B2 levels compared to cells treated by normal pregnancy plasma. The increasing of AT1-R expression significantly (P Punica granatum extract. Moreover, the increasing of thromboxane B2 levels significantly (P Punica granatum extract. We further concluded that Punica granatum fruit protects and inhibits the sensitivity of endothelial cells to plasma from preeclamptic patients due to inhibition of AT1-R expression (56 ppm) and reduced thromboxane B2 levels (14 ppm). PMID:26989513

  12. Depressor and Anti-Inflammatory Effects of Angiotensin II Receptor Blockers in Metabolic and/or Hypertensive Patients With Coronary Artery Disease: A Randomized, Prospective Study (DIAMOND Study)

    Science.gov (United States)

    Adachi, Sen; Miura, Shin-ichiro; Shiga, Yuhei; Arimura, Tadaaki; Kuwano, Takashi; Kitajima, Ken; Ike, Amane; Sugihara, Makoto; Iwata, Atsushi; Nishikawa, Hiroaki; Morito, Natsumi; Saku, Keijiro

    2016-01-01

    Background We compared the efficacy and safety of azilsartan to those of olmesartan in a prospective, randomized clinical trial. Methods Forty-four hypertensive patients who had coronary artery disease (CAD) were enrolled. We randomly assigned patients to changeover from their prior angiotensin II receptor blockers (ARBs) to either azilsartan or olmesartan, and followed the patients for 12 weeks. Results Office systolic blood pressure (SBP) in the azilsartan group was significantly decreased after 12 weeks. SBP and diastolic blood pressure (DBP) after 12 weeks in the azilsartan group were significantly lower than those in the olmesartan group. The percentage of patients who reached the target BP at 12 weeks (78%) in the azilsartan group was significantly higher than that at 12 weeks (45%) in the olmesartan group. There were no significant changes in pentraxin-3, high-sensitively C-reactive protein or adiponectin in blood after 12 weeks in either group. Although serum levels of creatinine (Cr) in the azilsartan group significantly increased, these changes were within the respective normal range. Conclusion In conclusion, the ability of azilsartan to reduce BP may be superior to that of prior ARBs with equivalent safety in hypertensive patients with CAD.

  13. Overexpression of angiotensin II type 1 receptor in breast cancer cells induces epithelial-mesenchymal transition and promotes tumor growth and angiogenesis.

    Science.gov (United States)

    Oh, Eunhye; Kim, Ji Young; Cho, Youngkwan; An, Hyunsook; Lee, Nahyun; Jo, Hunho; Ban, Changill; Seo, Jae Hong

    2016-06-01

    The angiotensin II type I receptor (AGTR1) has been implicated in diverse aspects of human disease, from the regulation of blood pressure and cardiovascular homeostasis to cancer progression. We sought to investigate the role of AGTR1 in cell proliferation, epithelial-mesenchymal transition (EMT), migration, invasion, angiogenesis and tumor growth in the breast cancer cell line MCF7. Stable overexpression of AGTR1 was associated with accelerated cell proliferation, concomitant with increased expression of survival factors including poly(ADP-ribose) polymerase (PARP) and X-linked inhibitor of apoptosis (XIAP), as well as extracellular signal-regulated kinase (ERK) activation. AGTR1-overexpressing MCF7 cells were more aggressive than their parent line, with significantly increased activity in migration and invasion assays. These observations were associated with changes in EMT markers, including reduced E-cadherin expression and increased p-Smad3, Smad4 and Snail levels. Treatment with the AGTR1 antagonist losartan attenuated these effects. AGTR1 overexpression also accelerated tumor growth and increased Ki-67 expression in a xenograft model. This was associated with increased tumor angiogenesis, as evidenced by a significant increase in microvessels in the intratumoral and peritumoral areas, and enhanced tumor invasion, with the latter response associated with increased EMT marker expression and matrix metallopeptidase 9 (MMP-9) upregulation. In vivo administration of losartan significantly reduced both tumor growth and angiogenesis. Our findings suggest that AGTR1 plays a significant role in tumor aggressiveness, and its inhibition may have therapeutic implications. PMID:26975580

  14. Effects related to gene-gene interactions of peroxisome proliferator-activated receptor on essential hypertension

    Institute of Scientific and Technical Information of China (English)

    俞浩

    2013-01-01

    Objective To explore the impact of the gene-gene interaction among the single nucleotide polymorphisms(SNPs) of peroxisome proliferator-activated receptorα/δ/γ on essential hypertension(EH).Methods

  15. Association between insertion/deletion polymorphism in angiotensin-converting enzyme gene and acute lung injury/acute respiratory distress syndrome: a meta-analysis

    Directory of Open Access Journals (Sweden)

    Matsuda Akihisa

    2012-08-01

    Full Text Available Abstract Background A previous meta-analysis reported a positive association between an insertion/deletion (I/D polymorphism in the angiotensin-converting enzyme gene (ACE and the risk of acute lung injury (ALI/acute respiratory distress syndrome (ARDS. Here, we updated this meta-analysis and additionally assessed the association of this polymorphism with ALI/ARDS mortality. Methods We searched electronic databases through October 2011 for the terms “angiotensin-converting enzyme gene”, “acute lung injury”, and “acute respiratory distress syndrome,” and reviewed all studies that reported the relationship of the I/D polymorphism in ACE with ALI/ARDS in humans. Seven studies met the inclusion criteria, comprising 532 ALI/ARDS patients, 3032 healthy controls, and 1432 patients without ALI/ARDS. We used three genetic models: the allele, dominant, and recessive models. Results The ACE I/D polymorphism was not associated with susceptibility to ALI/ARDS for any genetic model. However, the ACE I/D polymorphism was associated with the mortality risk of ALI/ARDS in Asian subjects ( Pallele Pdominant = 0.001, Precessive = 0.002. This finding remained significant after correction for multiple comparisons. Conclusions There is a possible association between the ACE I/D polymorphism genotype and the mortality risk of ALI/ARDS in Asians.

  16. Genetic and Functional Analysis of Androgen Receptor Gene Mutations

    NARCIS (Netherlands)

    H.T. Brüggenwirth (Hennie)

    1998-01-01

    textabstractNuclear hormone receptors (NHRs) are intermediary factors through which extracellular signals regulate expression of genes that are involved in homeostasis, development, and differentiation (Beato et al. '995, Mangelsdorf and Evans 1995). These receptors are characterized by a modular st

  17. Effects of angiotensin converting enzyme inhibitor, angio- tensin II type I receptor blocker and their combination on postinfarcted ventricular remodeling in rats

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Background Transforming growth factor (TGF) β1-Smads signal plays an important role in cardiac remodeling following myocardial infarction (MI). In addition, both angiotensin converting enzyme inhibitor (ACEI) and angiotensin II type I receptor blocker (ARB) can effectively prevent left ventricular remodeling. The current study focused on whether the combination of ACEI and ARB is more beneficial for preventing ventricular remodeling and whether Smad proteins mediate this beneficial effect.Results VW/BW significantly increased in the placebo groups compared with that in the control group (P<0.01). This increase was limited in ACEI, ARB, and combined groups (P<0.01 compared with placebo group). There was no significant difference among the three actively treated groups. Collagen was increased in placebo group (5.68±0.5)% compared with that in control group (P<0.01). ACEI, ARB and combined treatment attenuated this increase of collagen [(4.3±0.5)%, (3.5±0.5)%, (3.2±0.4)%] in comparison with that in placebo group (P<0.01 respectively). Combined treatment showed more significant effect on collagen deposition. EF and FS significantly decreased, LVDd and E/A significantly increased in placebo group compared with that in control group (P<0.01 respectively). ACEI, ARB and combined treatment ameliorated these indexes (P<0.01 compared with placebo group). The mRNA expression of TGFβ1, Smad 2, and Smad 3 (0.700±0.045, 0.959±0.037 and 0.850±0.051) increased in placebo group compared with that in control group (P<0.01). ACEI, ARB and combined treatment normalized the increase (P<0.01). Furthermore, ARB and combined treatment proved to be more effective in decreasing TGF β1 and Smad mRNA expression than ACEI treatment (P<0.01). The expression of Smad 2 and Smad 3 protein increased in placebo group compared with that in control group (P<0.01). ACEI, ARB and combined treatment normalized the increase (P<0.01). Furthermore, ARB and combined treatment proved to be more

  18. Design, synthesis, and evaluation of imidazo[4,5-c]pyridin-4-one derivatives with dual activity at angiotensin II type 1 receptor and peroxisome proliferator-activated receptor-γ.

    Science.gov (United States)

    Casimiro-Garcia, Agustin; Heemstra, Ronald J; Bigge, Christopher F; Chen, Jing; Ciske, Fred A; Davis, Jo Ann; Ellis, Teresa; Esmaeil, Nadia; Flynn, Declan; Han, Seungil; Jalaie, Mehran; Ohren, Jeffrey F; Powell, Noel A

    2013-02-01

    Identification of a series of imidazo[4,5-c]pyridin-4-one derivatives that act as dual angiotensin II type 1 (AT1) receptor antagonists and peroxisome proliferator-activated receptor-γ (PPARγ) partial agonists is described. Starting from a known AT1 antagonist template, conformational restriction was introduced by incorporation of an indane ring that when combined with appropriate substitution at the imidazo[4,5-c]pyridin-4-one provided novel series 5 possessing the desired dual activity. The mode of interaction of this series with PPARγ was corroborated through the X-ray crystal structure of 12b bound to the human PPARγ ligand binding domain. Modulation of activity at both receptors through substitution at the pyridone nitrogen led to the identification of potent dual AT1 antagonists/PPARγ partial agonists. Among them, 21b was identified possessing potent dual pharmacology (AT1 IC(50) = 7 nM; PPARγ EC(50) = 295 nM, 27% max) and good ADME properties. PMID:23265881

  19. Organization and expression of canine olfactory receptor genes.

    OpenAIRE

    Issel-Tarver, L; Rine, J

    1996-01-01

    Four members of the canine olfactory receptor gene family were characterized. The predicted proteins shared 40-64% identity with previously identified olfactory receptors. The four subfamilies identified in Southern hybridization experiments had as few as 2 and as many as 20 members. All four genes were expressed exclusively in olfactory epithelium. Expression of multiple members of the larger subfamilies was detected, suggesting that most if not all of the cross-hybridizing bands in genomic ...

  20. CRDB: Database of Chemosensory Receptor Gene Families in Vertebrate

    OpenAIRE

    Dong Dong; Ke Jin; Xiaoli Wu; Yang Zhong

    2012-01-01

    Chemosensory receptors (CR) are crucial for animals to sense the environmental changes and survive on earth. The emergence of whole-genome sequences provides us an opportunity to identify the entire CR gene repertoires. To completely gain more insight into the evolution of CR genes in vertebrates, we identified the nearly all CR genes in 25 vertebrates using homology-based approaches. Among these CR gene repertoires, nearly half of them were identified for the first time in those previously u...

  1. Angiotensin II reduces cardiac AdipoR1 expression through AT1 receptor/ROS/ERK1/2/c-Myc pathway.

    Directory of Open Access Journals (Sweden)

    Li Li

    Full Text Available Adiponectin, an abundant adipose tissue-derived protein, exerts protective effect against cardiovascular disease. Adiponectin receptors (AdipoR1 and AdipoR2 mediate the beneficial effects of adiponectin on the cardiovascular system. However, the alteration of AdipoRs in cardiac remodeling is not fully elucidated. Here, we investigated the effect of angiotensin II (AngII on cardiac AdipoRs expression and explored the possible molecular mechanism. AngII infusion into rats induced cardiac hypertrophy, reduced AdipoR1 but not AdipoR2 expression, and attenuated the phosphorylations of adenosine monophosphate-activated protein kinase and acetyl coenzyme A carboxylase, and those effects were all reversed by losartan, an AngII type 1 (AT1 receptor blocker. AngII reduced expression of AdipoR1 mRNA and protein in cultured neonatal rat cardiomyocytes, which was abolished by losartan, but not by PD123319, an AT2 receptor antagonist. The antioxidants including reactive oxygen species (ROS scavenger NAC, NADPH oxidase inhibitor apocynin, Nox2 inhibitor peptide gp91 ds-tat, and mitochondrial electron transport chain complex I inhibitor rotenone attenuated AngII-induced production of ROS and phosphorylation of extracellular signal-regulated kinase (ERK 1/2. AngII-reduced AdipoR1 expression was reversed by pretreatment with NAC, apocynin, gp91 ds-tat, rotenone, and an ERK1/2 inhibitor PD98059. Chromatin immunoprecipitation assay demonstrated that AngII provoked the recruitment of c-Myc onto the promoter region of AdipoR1, which was attenuated by PD98059. Moreover, AngII-induced DNA binding activity of c-Myc was inhibited by losartan, NAC, apocynin, gp91 ds-tat, rotenone, and PD98059. c-Myc small interfering RNA abolished the inhibitory effect of AngII on AdipoR1 expression. Our results suggest that AngII inhibits cardiac AdipoR1 expression in vivo and in vitro and AT1 receptor/ROS/ERK1/2/c-Myc pathway is required for the downregulation of AdipoR1 induced by AngII.

  2. Angiotensin-converting enzyme 2/angiotensin-(1-7)/Mas axis activates Akt signaling to ameliorate hepatic steatosis.

    Science.gov (United States)

    Cao, Xi; Yang, Fangyuan; Shi, Tingting; Yuan, Mingxia; Xin, Zhong; Xie, Rongrong; Li, Sen; Li, Hongbing; Yang, Jin-Kui

    2016-01-01

    The classical axis of renin-angiotensin system (RAS), angiotensin (Ang)-converting enzyme (ACE)/Ang II/AT1, contributes to the development of non-alcoholic fatty liver disease (NAFLD). However, the role of bypass axis of RAS (Angiotensin-converting enzyme 2 (ACE2)/Ang-(1-7)/Mas) in hepatic steatosis is still unclear. Here we showed that deletion of ACE2 aggravates liver steatosis, which is correlated with the increased expression of hepatic lipogenic genes and the decreased expression of fatty acid oxidation-related genes in the liver of ACE2 knockout (ACE2(-/y)) mice. Meanwhile, oxidative stress and inflammation were also aggravated in ACE2(-/y) mice. On the contrary, overexpression of ACE2 improved fatty liver in db/db mice, and the mRNA levels of fatty acid oxidation-related genes were up-regulated. In vitro, Ang-(1-7)/ACE2 ameliorated hepatic steatosis, oxidative stress and inflammation in free fatty acid (FFA)-induced HepG2 cells, and what's more, Akt inhibitors reduced ACE2-mediated lipid metabolism. Furthermore, ACE2-mediated Akt activation could be attenuated by blockade of ATP/P2 receptor/Calmodulin (CaM) pathway. These results indicated that Ang-(1-7)/ACE2/Mas axis may reduce liver lipid accumulation partly by regulating lipid-metabolizing genes through ATP/P2 receptor/CaM signaling pathway. Our findings support the potential role of ACE2/Ang-(1-7)/Mas axis in prevention and treatment of hepatic lipid metabolism. PMID:26883384

  3. Regulation of gonadotropin receptor gene expression

    NARCIS (Netherlands)

    A.P.N. Themmen (Axel); R. Kraaij (Robert); J.A. Grootegoed (Anton)

    1994-01-01

    textabstractThe receptors for the gonadotropins differ from the other G protein-coupled receptors by having a large extracellular hormone-binding domain, encoded by nine or ten exons. Alternative splicing of the large pre-mRNA of approximately 100 kb can result in mRNA species that encode truncated

  4. Cooperative Role of Mineralocorticoid Receptor and Caveolin-1 in Regulating the Vascular Response to Low Nitric Oxide-High Angiotensin II-Induced Cardiovascular Injury.

    Science.gov (United States)

    Pojoga, Luminita H; Yao, Tham M; Opsasnick, Lauren A; Siddiqui, Waleed T; Reslan, Ossama M; Adler, Gail K; Williams, Gordon H; Khalil, Raouf A

    2015-10-01

    Aldosterone interacts with mineralocorticoid receptor (MR) to stimulate sodium reabsorption in renal tubules and may also affect the vasculature. Caveolin-1 (cav-1), an anchoring protein in plasmalemmal caveolae, binds steroid receptors and also endothelial nitric oxide synthase, thus limiting its translocation and activation. To test for potential MR/cav-1 interaction in the vasculature, we investigated if MR blockade in cav-1-replete or -deficient states would alter vascular function in a mouse model of low nitric oxide (NO)-high angiotensin II (AngII)-induced cardiovascular injury. Wild-type (WT) and cav-1 knockout mice (cav-1(-/-)) consuming a high salt diet (4% NaCl) received Nω-nitro-l-arginine methyl ester (L-NAME) (0.1-0.2 mg/ml in drinking water at days 1-11) plus AngII (0.7-2.8 mg/kg per day via an osmotic minipump at days 8-11) ± MR antagonist eplerenone (EPL) 100 mg/kg per day in food. In both genotypes, blood pressure increased with L-NAME + AngII. EPL minimally changed blood pressure, although its dose was sufficient to block MR and reverse cardiac expression of the injury markers cluster of differentiation 68 and plasminogen activator inhibitor-1 in L-NAME+AngII treated mice. In aortic rings, phenylephrine and KCl contraction was enhanced with EPL in L-NAME+AngII treated WT mice, but not cav-1(-/-) mice. AngII-induced contraction was not different, and angiotensin type 1 receptor expression was reduced in L-NAME + AngII treated WT and cav-1(-/-) mice. In WT mice, acetylcholine-induced relaxation was enhanced with L-NAME + AngII treatment and reversed with EPL. Acetylcholine relaxation in cav-1(-/-) mice was greater than in WT mice, not modified by L-NAME + AngII or EPL, and blocked by ex vivo L-NAME, 1H-(1,2,4)oxadiazolo(4,3-a)quinoxalin-1-one (ODQ), or endothelium removal, suggesting the role of NO-cGMP. Cardiac endothelial NO synthase was increased in cav-1(-/-) versus WT mice, further increased with L-NAME + AngII, and not affected by EPL

  5. Prevention of diabetic nephropathy by compound 21, selective agonist of angiotensin type 2 receptors, in Zucker diabetic fatty rats

    DEFF Research Database (Denmark)

    Castoldi, Giovanna; di Gioia, Cira Rt; Bombardi, Camila;

    2014-01-01

    Aim of the study was to evaluate the effect of compound 21 (C21), selective AT2 receptor agonist, in diabetic nephropathy and the potential additive effect of C21, when associated to losartan treatment, on the development of albuminuria and renal fibrosis in Zucker diabetic fatty (ZDF) rats. The ...

  6. Vitamin D receptor and estrogen receptor gene polymorphisms in postmenopausal Danish women

    DEFF Research Database (Denmark)

    Bagger, Y Z; Hassager, C; Heegaard, Anne-Marie;

    2000-01-01

    To investigate the polymorphisms of the vitamin D receptor (VDR) and estrogen receptor (ER) genes in relation to biochemical markers of bone turnover (serum osteocalcin and urinary collagen type I degradation products (CrossLaps), and to study ER genotypes in relation to serum lipoproteins, blood...

  7. Association of Interleukin 23 Receptor Gene with Sarcoidosis

    Directory of Open Access Journals (Sweden)

    Hyun Soo Kim

    2011-01-01

    Full Text Available Interleukin 23 receptor (IL23R gene has been reported as a genetic factor strongly associated with inflammatory bowel disease, psoriasis, and ankylosing spondylitis. We investigated the association between IL23R gene single nucleotide polymorphisms (SNPs and susceptibility to sarcoidosis, including the clinical manifestation of uveitis.

  8. Angiotensin type 1a receptors in the forebrain subfornical organ facilitate leptin-induced weight loss through brown adipose tissue thermogenesis

    Directory of Open Access Journals (Sweden)

    Colin N. Young

    2015-04-01

    Conclusions: These data identify a novel interaction between angiotensin-II and leptin in the control of BAT thermogenesis and body weight, and highlight a previously unrecognized role for the forebrain SFO in metabolic regulation.

  9. Prolactin receptor and signal transduction to milk protein genes

    Energy Technology Data Exchange (ETDEWEB)

    Djiane, J.; Daniel, N.; Bignon, C. [Unite d`Endocrinologie Moleculaire, Jouy en Josas (France)] [and others

    1994-06-01

    After cloning of the mammary gland prolactin (PRL) receptor cDNA, a functional assay was established using co-transfection of PRL receptor cDNA together with a milk protein promoter/chloramphenicol acetyl transferase (CAT) construct in Chinese hamster ovary (CHO) cells. Different mutants of the PRL receptor were tested in this CAT assay to delimit the domains in the receptor necessary for signal transduction to milk protein genes. In CHO cells stably transfected with PRL receptor cDNA, high numbers of PRL receptor are expressed. By metabolic labeling and immunoprecipitation, expressed PRL receptor was identified as a single species of 100 kDa. Using these cells, we analyzed the effects of PRL on intracellular free Ca{sup ++} concentration. PRL stimulates Ca{sup ++} entry and induces secondary Ca{sup ++} mobilization. The entry of Ca{sup ++} is a result of an increase in K{sup +} conductance that hyperpolarizes the membranes. We have also analyzed tyrosine phosphorylation induced by PRL. In CHO cells stably transfected with PRL receptor cDNA, PRL induced a very rapid and transient tyrosine phosphorylation of a 100-kDa protein which is most probably the PRL receptor. The same finding was obtained in mammary membranes after PRL injection to lactating rabbits. Whereas tyrosine kinase inhibitors genistein and lavendustin were without effect, PRL stimulation of milk protein gene promoters was partially inhibited by 2 {mu}M herbimycin in CHO cells co-transfected with PRL receptor cDNA and the {Beta} lactoglobulin CAT construct. Taken together these observations indicate that the cytoplasmic domain of the PRL receptor interacts with one or several tyrosine kinases, which may represent early postreceptor events necessary for PRL signal transduction to milk protein genes. 14 refs., 4 figs.

  10. Epidermal growth factor (EGF) receptor gene transcription

    International Nuclear Information System (INIS)

    The authors have studied in vitro transcription of the human epidermal growth factor (EGF) receptor proto-oncogene using nuclear extracts of A431 human epidermoid carcinoma cells, which overproduce the EGF receptor. With the in vitro system we found that Sp1 and other trans-acting factors bound to the EGF receptor promoter regions and are required for maximal expression. Fractionation showed that a DEAE-Sepharose fraction (BA) contained a novel factor, which specifically stimulated EGF receptor transcription 5- to 10-fold. The molecular mass of the native form of the factor is about 270-kDa based on its migration on Sephacryl S-300. This factor may activate transcription of the proto-oncogene through a weak or indirect interaction with the DNA template

  11. Mechanisms of fetal and neonatal renal impairment by pharmacologic inhibition of angiotensin.

    Science.gov (United States)

    Chevalier, Robert L

    2012-01-01

    The renin-angiotensin system is highly conserved through evolutionary history, and has multiple functions in addition to maintaining cardiovascular homeostasis: these include the regulation of renal cell survival and cell death, and development of the kidney. The importance of angiotensin (ANG) in normal kidney development was first recognized in infants with renal maldevelopment born to mothers treated with angiotensin converting enzyme (ACE) inhibitors or with ANG AT1 receptor blockers. The molecular role of ANG in renal development has been elucidated using gene targeting in mice, revealing major effects in branching morphogenesis, vasculogenesis, development of the papilla and renal concentrating mechanism. Although exposure of the fetus to ANG inhibitors is potentially harmful throughout pregnancy, effects are greater in late compared to early gestation. Significant differences between humans and rodents in placental transfer of ANG and timing of renal development contributed to initial delays in recognizing the teratogenic effects of ANG inhibitors. Although administration of ACE or AT1 receptor inhibitors can slow progression of renal disease in older children, ANG inhibition in the neonatal period can aggravate renal injury due to congenital urinary tract obstruction. Neonates are also far more sensitive than older children to the hypotensive actions these agents and doses must be markedly reduced to avoid precipitating oliguria. Understanding the complex interactions of the maturing renin-angiotensin system in the perinatal period is essential in the use of ANG or renin inhibitors in women during childbearing years or in neonates with cardiovascular or renal disease. PMID:22876894

  12. Pharmacokinetic drug-drug interaction assessment of LCZ696 (an angiotensin receptor neprilysin inhibitor) with omeprazole, metformin or levonorgestrel-ethinyl estradiol in healthy subjects.

    Science.gov (United States)

    Gan, Lu; Jiang, Xuemin; Mendonza, Anisha; Swan, Therese; Reynolds, Christine; Nguyen, Joanne; Pal, Parasar; Neelakantham, Srikanth; Dahlke, Marion; Langenickel, Thomas; Rajman, Iris; Akahori, Mizuki; Zhou, Wei; Rebello, Sam; Sunkara, Gangadhar

    2016-01-01

    LCZ696 is a novel angiotensin receptor neprilysin inhibitor in development for the treatment of cardiovascular diseases. Here, we assessed the potential for pharmacokinetic drug-drug interaction of LCZ696 (400 mg, single dose or once daily [q.d.]) when co-administered with omeprazole 40 mg q.d. (n = 28) or metformin 1000 mg q.d. (n = 27) or levonorgestrel-ethinyl estradiol 150/30 μg single dose (n = 24) in three separate open-label, single-sequence studies in healthy subjects. Pharmacokinetic parameters of LCZ696 analytes (sacubitril, LBQ657, and valsartan), metformin, and levonorgestrel-ethinyl estradiol were assessed. Omeprazole did not alter the AUCinf of sacubitril and pharmacokinetics of LBQ657; however, 7% decrease in the Cmax of sacubitril, and 11% and 13% decreases in AUCinf and Cmax of valsartan were observed. Co-administration of LCZ696 with metformin had no significant effect on the pharmacokinetics of LBQ657 and valsartan; however, AUCtau,ss and Cmax,ss of metformin were decreased by 23%. Co-administration of LCZ696 with levonorgestrel-ethinyl estradiol had no effect on the pharmacokinetics of ethinyl estradiol and LBQ657 or AUCinf of levonorgestrel. The Cmax of levonorgestrel decreased by 15%, and AUCtau,ss and Cmax,ss of valsartan decreased by 14% and 16%, respectively. Co-administration of LCZ696 with omeprazole, metformin, or levonorgestrel-ethinyl estradiol was not associated with any clinically relevant pharmacokinetic drug interactions. PMID:27119576

  13. Angiotensin II type 2 receptor promotes adipocyte differentiation and restores adipocyte size in high-fat/high-fructose diet-induced insulin resistance in rats.

    Science.gov (United States)

    Shum, Michaël; Pinard, Sandra; Guimond, Marie-Odile; Labbé, Sébastien M; Roberge, Claude; Baillargeon, Jean-Patrice; Langlois, Marie-France; Alterman, Mathias; Wallinder, Charlotta; Hallberg, Anders; Carpentier, André C; Gallo-Payet, Nicole

    2013-01-15

    This study was aimed at establishing whether specific activation of angiotensin II (ANG II) type 2 receptor (AT2R) modulates adipocyte differentiation and function. In primary cultures of subcutaneous (SC) and retroperitoneal (RET) preadipocytes, both AT2R and AT1R were expressed at the mRNA and protein level. Cells were stimulated with ANG II or the AT2R agonist C21/M24, alone or in the presence of the AT1R antagonist losartan or the AT2R antagonist PD123,319. During differentiation, C21/M24 increased PPARγ expression in both RET and SC preadipocytes while the number of small lipid droplets and lipid accumulation solely increased in SC preadipocytes. In mature adipocytes, C21/M24 decreased the mean size of large lipid droplets. Upon abolishment of AT2R expression using AT2R-targeted shRNAs, expressions of AT2R, aP2, and PPARγ remained very low, and cells were unable to differentiate. In Wistar rats fed a 6-wk high-fat/high-fructose (HFHF) diet, a significant shift toward larger adipocytes was observed in RET and SC adipose tissue depots. C21/M24 treatments for 6 wk restored normal adipocyte size distribution in both these tissue depots. Moreover, C21/M24 and losartan decreased hyperinsulinemia and improved insulin sensitivity impaired by HFHF diet. A strong correlation between adipocyte size area and glucose infusion rate during euglycemic-hyperinsulinemic clamp was observed. These results indicate that AT2R is involved in early adipocyte differentiation, while in mature adipocytes and in a model of insulin resistance AT2R activation restores normal adipocyte morphology and improves insulin sensitivity. PMID:23149621

  14. Low sodium diet inhibits the local counter-regulator effect of angiotensin-(1-7) on angiotensin II

    NARCIS (Netherlands)

    Roks, Anton J M; Nijholt, Jeroen; van Buiten, Azuwerus; van Gilst, Wiek H; de Zeeuw, Dick; Henning, Robert H

    2004-01-01

    OBJECTIVE: The heptapeptide angiotensin-(1-7) [Ang-(1-7)] has been identified as a versatile, endogenous inhibitor of the renin-angiotensin system (RAS). As the therapeutic response to exogenous RAS inhibitors, such as AT1 receptor antagonists, is altered by changes in salt intake, we investigated t

  15. Low sodium diet inhibits the local counter-regulator effect of angiotensin-(1-7) on angiotensin II

    NARCIS (Netherlands)

    Roks, AJM; Nijholt, J; van Buiten, A; van Gilst, WH; de Zeeuw, D; Henning, RH

    2004-01-01

    Objective The heptapeptide angiotensin-(1-7) [Ang-(1-7)] has been identified as a versatile, endogenous inhibitor of the renin-angiotensin system (RAS). As the therapeutic response to exogenous RAS inhibitors, such as AT, receptor antagonists, is altered by changes in salt intake, we investigated th

  16. Dopamine receptor gene expression by enkephalin neurons in rat forebrain

    International Nuclear Information System (INIS)

    In situ hybridization experiments were performed with brain sections from normal, control and haloperidol-treated rats to identify and map the cells expressing the D2 dopamine receptor gene. D2 receptor mRNA was detected with radioactive or biotinylated oligonucleotide probes. D2 receptor mRNA was present in glandular cells of the pituitary intermediate lobe and in neurons of the substantia nigra, ventral tegmental area, and forebrain, especially in caudate putamen, nucleus accumbens, olfactory tubercle, and piriform cortex. Hybridization with D2 and preproenkephalin A probes in adjacent sections, as well as combined hybridization with the two probes in the same sections, demonstrated that all detectable enkephalin neurons in the striatum contained the D2 receptor mRNA. Large neurons in caudate putamen, which were unlabeled with the preproenkephalin A probe and which may have been cholinergic, also expressed the D2 receptor gene. Haloperidol treatment (14 or 21 days) provoked an increase in mRNA content for D2 receptor and preproenkephalin A in the striatum. This suggests that the increase in D2 receptor number observed after haloperidol treatment is due to increased activity of the D2 gene. These results indicate that in the striatum, the enkephalin neurons are direct targets for dopamine liberated from mesostriatal neurons

  17. Bradykinin Type 2 Receptor BE1 Genotype Influences Bradykinin-Dependent Vasodilation During Angiotensin-Converting Enzyme Inhibition

    OpenAIRE

    Van Guilder, Gary P.; Pretorius, Mias; Luther, James M.; Byrd, J. Brian; Hill, Kevin; Gainer, James V.; Brown, Nancy J.

    2008-01-01

    To test the hypothesis that the bradykinin receptor 2 (BDKRB2) BE1 +9/−9 polymorphism affects vascular responses to bradykinin, we measured the effect of intra-arterial bradykinin on forearm blood flow and tissue-type plasminogen activator (t-PA) release in 89 normotensive, nonsmoking, white American subjects in whom degradation of bradykinin was blocked by enalaprilat. BE1 genotype frequencies were +9/+9:+9/−9:−9/−9=19:42:28. BE1 genotype was associated with systolic blood pressure (121.4±2....

  18. Androgen receptor gene mutations in 46, XY females

    Directory of Open Access Journals (Sweden)

    Mir Davood Omrani

    2006-12-01

    Full Text Available The androgen insensitivity syndrome is a heterogeneous disorder with a wide spectrum of phenotypic abnormalities, ranging from complete female to ambiguous forms that more closely resemble males. The primary abnormality is a defective androgen receptor protein due to a mutation of the androgen receptor gene. This prevents normal androgen action and thus leads to impaired virilization. A point mutation of the androgen receptor gene affecting two siblings with complete androgen insensitivity syndrome is described. On examination they both had normal external female genitalia. Genomic DNA was extracted from EDTA-preserved blood samples and isolated according to standard procedures. The androgen receptor gene was screened for mutations using an automated sequence analyzer (ABI Prism 310. Both girls possess one substitutions (G>A at position 2086 in exon 4, leading to D695N mutation. Mother was found to be a heterozygous carrier for this mutation. GTG banded karyotype of the girls showed they both have male karyotype (46, XY. In addition, the SRY gene screening showed they both have intact SRY gene. The labioscrotal folds contained palpable gonads measuring 1.5 cm in largest diameter. Ultrasound examination of the pelvis revealed absence of the uterus. Serum follicle stimulating hormone (FSH, luteinizing hormone (LH, and testosterone values were higher than normal range. To our knowledge this is the first confirmed instance of AIS due to an AR mutation occurring in familial cases in this country. Furthermore, the phenotype has complete association with this mutation. KEY WORDS: Androgen insensitivity syndrome, androgen receptor

  19. Targeted gene delivery via N-acetylglucosamine receptor mediated endocytosis.

    Science.gov (United States)

    Singh, Bijay; Maharjan, Sushila; Kim, You-Kyoung; Jiang, Tai; Islam, Mohammad Ariful; Kang, Sang-Kee; Cho, Myung-Haing; Choi, Yun-Jaie; Cho, Chong-Su

    2014-11-01

    Receptor-mediated endocytosis is a promising approach of gene delivery into the target cells via receptor-ligand interaction. Vimentins at the cell surface are recently known to bind N-acetylglucosamine (GlcNAc) residue, therefore, the cell surfaces of vimentin-expressing cells could be targeted by using the GlcNAc residue as a specific ligand for receptor-mediated gene delivery. Here, we have developed polymeric gene delivery vectors, based on poly(ethylene oxide)(PEO) and poly(aspartamide), namely poly[(aspartamide)(diethylenetriamine)]-b-[PEO-(GlcNAc)] (PADPG) and poly[(aspartamide)(diethylenetriamine)]-b-[PEO] (PADP) to elucidate the efficiency of GlcNAc ligand for gene delivery through receptor mediated endocytosis. To determine the efficiency of these polymeric vectors for specific gene delivery, the DNA condensation ability of PADPG and PADP and the subsequent formation of polymeric nanoparticles were confirmed by gel retardation assay and transmission electron microscopy respectively. Both PADPG and PADP had lower cytotoxicity than polyethylenimine 25 K (PEI 25 K). However, their transfection efficiency was comparatively lower than PEI 25 K due to hydrophilic property of PEO in the vectors. To observe the stability of polymeric nanoparticles, the transfection of PADPG and PADP was carried out in the presence of serum. Favorably, the interfering effect of serum on the transfection efficiency of PADPG and PADP was also very low. Finally, when the cell specificity of these polymeric vectors was investigated, PADPG had high gene transfection in vimentin-expressing cells than vimentin-deficiency cells. The high transfection efficiency of PADPG was attributed to the GlcNAc in the polymeric vector which interact specifically with vimentin in the cells for the receptor-mediated endocytosis. The competitive inhibition assay further proved the receptor-mediated endocytosis of PADPG. Thus, this study demonstrates that conjugation of GlcNAc is an effective and rational

  20. Angiotensin II-Induced Migration of Vascular Smooth Muscle Cells Is Mediated by p38 Mitogen-Activated Protein Kinase-Activated c-Src Through Spleen Tyrosine Kinase and Epidermal Growth Factor Receptor Transactivation

    OpenAIRE

    Mugabe, Benon E.; Yaghini, Fariborz A.; Song, Chi Young; Buharalioglu, Cuneyt K.; Waters, Christopher M.; Malik, Kafait U.

    2010-01-01

    Angiotensin II (Ang II) stimulates protein synthesis by activating spleen tyrosine kinase (Syk) and DNA synthesis through epidermal growth factor receptor (EGFR) transactivation in vascular smooth muscle cells (VSMCs). This study was conducted to determine whether Syk mediates Ang II-induced migration of aortic VSMCs using a scratch wound approach. Treatment with Ang II (200 nM) for 24 h increased VSMC migration by 1.56 ± 0.14-fold. Ang II-induced VSMC migration and Syk phosphorylation as det...

  1. Glial high-affinity binding site with specificity for angiotensin II not angiotensin III: a possible N-terminal-specific converting enzyme

    Energy Technology Data Exchange (ETDEWEB)

    Printz, M.P.; Jennings, C.; Healy, D.P.; Kalter, V.

    1986-01-01

    Anomalous binding properties of angiotensin II to fetal rat brain primary cultures suggested a possible contribution from contaminating glia. To investigate this possibility, cultures of C6 glioma, a clonal rat cell line, were examined for the presence of angiotensin II receptors. A specific high-affinity site for (/sup 125/I)angiotensin II was measured both by traditional methodology using whole cells and by autoradiography. This site shared properties similar to that found with the brain cells, namely low ligand internalization and markedly decreased affinity for N-terminal sarcosine or arginine-angiotensin analogs. The competition rank order was angiotensin II much greater than (Sar1,Ile8)angiotensin II greater than or equal to des(Asp1,Arg2)angiotensin II. Angiotensin III did not compete for binding to the site. High-pressure liquid chromatography analysis indicated that the ligand either in the incubation or bound to the site was stable at 15 degrees C, but there was very rapid and extensive degradation by the C6 glioma cells at 37 degrees C. It is concluded that the site exhibits unusual N-terminal specificity for angiotensin with nanomolar affinity for angiotensin II. If angiotensin III is an active ligand in the brain, the site may have a converting enzyme function. Alternatively, it may form the des-Asp derivatives of angiotensin for subsequent degradation by other enzymatic pathways. Either way, it is proposed that the site may modulate the brain-angiotensin system.

  2. Angiotensin II type 1 receptor blockade partially attenuates hypoxia-induced pulmonary hypertension in newborn piglets: relationship with the nitrergic system

    Energy Technology Data Exchange (ETDEWEB)

    Camelo, J.S. Jr. [Departamento de Puericultura e Pediatria, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Martins, A.R. [Departamento de Farmacologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Instituto de Ciências Biológicas, Universidade Federal do Triângulo Mineiro, Uberaba, MG (Brazil); Rosa, E. [Departamento de Farmacologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Ramos, S.G. [Departamento de Patologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SPBrasil (Brazil); Hehre, D.; Bancalari, E.; Suguihara, C. [Department of Pediatrics, Division of Neonatology, Neonatal Developmental Biology Laboratory, University of Miami Miller School of Medicine, Miami, FL (United States)

    2012-02-10

    The objective of this study was to observe possible interactions between the renin-angiotensin and nitrergic systems in chronic hypoxia-induced pulmonary hypertension in newborn piglets. Thirteen chronically instrumented newborn piglets (6.3 ± 0.9 days; 2369 ± 491 g) were randomly assigned to receive saline (placebo, P) or the AT{sub 1} receptor (AT{sub 1}-R) blocker L-158,809 (L) during 6 days of hypoxia (FiO{sub 2} = 0.12). During hypoxia, pulmonary arterial pressure (Ppa; P < 0.0001), pulmonary vascular resistance (PVR; P < 0.02) and the pulmonary to systemic vascular resistance ratio (PVR/SVR; P < 0.05) were significantly attenuated in the L (N = 7) group compared to the P group (N = 6). Western blot analysis of lung proteins showed a significant decrease of endothelial NOS (eNOS) in both P and L animals, and of AT{sub 1}-R in P animals during hypoxia compared to normoxic animals (C group, N = 5; P < 0.01 for all groups). AT{sub 1}-R tended to decrease in L animals. Inducible NOS (iNOS) did not differ among P, L, and C animals and iNOS immunohistochemical staining in macrophages was significantly more intense in L than in P animals (P < 0.01). The vascular endothelium showed moderate or strong eNOS and AT{sub 1}-R staining. Macrophages and pneumocytes showed moderate or strong iNOS and AT{sub 1}-R staining, but C animals showed weak iNOS and AT{sub 1}-R staining. Macrophages of L and P animals showed moderate and weak AT{sub 2}-R staining, respectively, but the endothelium of all groups only showed weak staining. In conclusion, pulmonary hypertension induced by chronic hypoxia in newborn piglets is partially attenuated by AT{sub 1}-R blockade. We suggest that AT{sub 1}-R blockade might act through AT{sub 2}-R and/or Mas receptors and the nitrergic system in the lungs of hypoxemic newborn piglets.

  3. The effects of repeated delivery of angiotensin II AT1 receptor antisense on distinct vasoactive systems in Ren-2 transgenic rats: young vs. adult animals

    Czech Academy of Sciences Publication Activity Database

    Vaněčková, Ivana; Dobešová, Zdenka; Kuneš, Jaroslav; Zicha, Josef

    2012-01-01

    Roč. 35, č. 7 (2012), s. 761-768. ISSN 0916-9636 R&D Projects: GA AV ČR(CZ) IAA500110902; GA ČR(CZ) GAP304/12/0259 Institutional support: RVO:67985823 Keywords : AT(1) receptor * BP regulation * gene therapy * oligodeoxynucleotides * vasodilator and vasoconstrictor systems Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 2.791, year: 2012

  4. A Coordination Model of Gene Sequences for SARS-CoV and its Receptor

    Institute of Scientific and Technical Information of China (English)

    SHAO Shi-huang; DAI Hua; GAO Lei; HUANG Ying-Song; HUANG Zhen-de; DING Yong-sheng

    2004-01-01

    A Z curve-based coordination model of genome sequences for the interaction of the SARS coronavirus (SARS-CoV) with its receptor, angiotensin-converting enzyme 2 (ACE2) is proposed. The model provides a novel, intuitive tool for visualizing and analyzing DNA sequences of SARS. It will be useful to the analysis of SARS-CoV in lab detection. Also, it can be used as a solution to other studies in bioinformatics field.

  5. Molecular-genetic risk assessement of determining angiotensin-converting enzyme hyperactivity in hemorrhagic fever with renal syndrome

    Directory of Open Access Journals (Sweden)

    Ildar R. Minniakhmetov

    2012-09-01

    Full Text Available The present study was designed to investigate changes in angiotensin-converting enzyme (ACE blood activity and angiotensin II type 1 receptor gene polymorphism as a possible disease predictor in hemorrhagic fever with renal syndrome (HFRS. Four hundred and nine patients (346 males and 63 females with HFRS serologic confirmation were enrolled in the study. Their age ranged from 15 to 65 years. ACE blood activity was assessed kinetically using the Bühlmann (Switzerland kit. Peripheral blood genomic DNA was isolated by a phenol-chloroform extraction. The genotyping of DNA loci was done using a polymerase chain reaction of DNA synthesis. Statistically, ACE blood activity was significantly higher throughout the entire HFRS course with diverse severity apart from the feverish phase of moderate-to-severe uncomplicated disease forms. *A1166 and *C1166 alleles, *A1166/*A1166 and *C1166/*C1166 genotypes of angiotensin II type 1 receptor gene were not associated with HFRS severity. The results of this study indicate that high ACE activity has not adaptive characteristics due to abnormalities in angiotensin II reception. It is an adequate metabolic response of the body to endotheliotropic virus activity.

  6. Angiotensin II during experimentally simulated central hypovolemia

    Directory of Open Access Journals (Sweden)

    Theo Walther Jensen

    2016-03-01

    Full Text Available Abstract:Central hypovolemia, defined as diminished blood volume in the heart and pulmonary vascular bed, is still an unresolved problem from a therapeutic point of view. The development of pharmaceutical agents targeted at specific angiotensin II receptors, like the non-peptidergic AT2-receptor agonist compound 21, is yielding many opportunities to uncover more knowledge about angiotensin II receptor profiles and possible therapeutic use. Cardiovascular, anti-inflammatory and neuroprotective therapeutic use of compound 21 have been suggested. However, there has not yet been a focus on the use of these agents in a hypovolemic setting. We argue that the latest debates on the effect of angiotensin II during hypovolemia might guide for future studies investigating the effect of such agents during experimentally simulated central hypovolemia. The purpose of this review is to examine the role of angiotensin II during episodes of central hypovolemia.To examine this, we reviewed results from studies with three experimental models of simulated hypovolemia: head up tilt table test, lower body negative pressure, and hemorrhage of animals. A systemic literature search was made with the use of PubMed/MEDLINE for studies that measured variables of the renin-angiotensin system or its effect during simulated hypovolemia. 12 articles, using one of the three models, were included and showed a possible organ protective effect and an effect on the sympathetic system of angiotensin II during hypovolemia. The results support the possible organ protective vasodilatory role for the AT2-receptor during hypovolemia on both the kidney and the splanchnic tissue.

  7. Reversible renal impairment induced by treatment with the angiotensin II receptor antagonist candesartan in a patient with bilateral renal artery stenosis

    Directory of Open Access Journals (Sweden)

    Kjaer Andreas

    2001-05-01

    Full Text Available Abstract Background It is well established that ACE-inhibitors should be avoided in patients with renal artery stenosis. In recent years it has also been recommended that caution should be demonstrated when angiotensin II blockers are used in the same type of patients but the evidence is based only on few cases. Results We describe a case where use of the angiotensin II antagonist candesartan (Atacand induced renal failure in a patient with bilateral renal artery stenosis. The course of the case is enlighted by results from sequential renography, selective renal vein catheterisation for measurement of renin, and angiographic findings. Conclusions In patients with renal artery stenosis the angiotensin II antagonist candesartan should be avoided.

  8. Variability of the Transferrin Receptor 2 Gene in AMD

    OpenAIRE

    2014-01-01

    Oxidative stress is a major factor in the pathogenesis of age-related macular degeneration (AMD). Iron may catalyze the Fenton reaction resulting in overproduction of reactive oxygen species. Transferrin receptor 2 plays a critical role in iron homeostasis and variability in its gene may influence oxidative stress and AMD occurrence. To verify this hypothesis we assessed the association between polymorphisms of the TFR2 gene and AMD. A total of 493 AMD patients and 171 matched controls were g...

  9. Evidence for angiotensin II type 2 receptor–mediated cardiac myocyte enlargement during in vivo pressure overload

    OpenAIRE

    Senbonmatsu, Takaaki; Ichihara, Sahoko; Price, Edward; Gaffney, F.Andrew; Inagami, Tadashi

    2000-01-01

    The pathophysiological roles of the angiotensin II type 2 receptor (AT2) in cardiac hypertrophy remain unclear. By the targeted deletion of mouse AT2 we were able to prevent the left ventricular hypertrophy resulting from pressure overload, while cardiac contractile functions remained normal. This implies that AT2 is a mediator of cardiac hypertrophy in response to increased blood pressure. The effects of AT2 deletion were independent of activation of embryonic genes for cardiac hypertrophy. ...

  10. Expression of serotonin receptor genes in cranial ganglia.

    Science.gov (United States)

    Maeda, Naohiro; Ohmoto, Makoto; Yamamoto, Kurumi; Kurokawa, Azusa; Narukawa, Masataka; Ishimaru, Yoshiro; Misaka, Takumi; Matsumoto, Ichiro; Abe, Keiko

    2016-03-23

    Taste cells release neurotransmitters to gustatory neurons to transmit chemical information they received. Sweet, umami, and bitter taste cells use ATP as a neurotransmitter. However, ATP release from sour taste cells has not been observed so far. Instead, they release serotonin when they are activated by sour/acid stimuli. Thus it is still controversial whether sour taste cells use ATP, serotonin, or both. By reverse transcription-polymerase chain reaction and subsequent in situ hybridization (ISH) analyses, we revealed that of 14 serotonin receptor genes only 5-HT3A and 5-HT3B showed significant/clear signals in a subset of neurons of cranial sensory ganglia in which gustatory neurons reside. Double-fluorescent labeling analyses of ISH for serotonin receptor genes with wheat germ agglutinin (WGA) in cranial sensory ganglia of pkd1l3-WGA mice whose sour neural pathway is visualized by the distribution of WGA originating from sour taste cells in the posterior region of the tongue revealed that WGA-positive cranial sensory neurons rarely express either of serotonin receptor gene. These results suggest that serotonin receptors expressed in cranial sensory neurons do not play any role as neurotransmitter receptor from sour taste cells. PMID:26854841

  11. Angiotensin II-induced Akt activation through the epidermal growth factor receptor in vascular smooth muscle cells is mediated by phospholipid metabolites derived by activation of phospholipase D.

    Science.gov (United States)

    Li, Fang; Malik, Kafait U

    2005-03-01

    Angiotensin II (Ang II) activates cytosolic Ca(2+)-dependent phospholipase A(2) (cPLA(2)), phospholipase D (PLD), p38 mitogen-activated protein kinase (MAPK), epidermal growth factor receptor (EGFR) and Akt in vascular smooth muscle cells (VSMC). This study was conducted to investigate the relationship between Akt activation by Ang II and other signaling molecules in rat VSMC. Ang II-induced Akt phosphorylation was significantly reduced by the PLD inhibitor 1-butanol, but not by its inactive analog 2-butanol, and by brefeldin A, an inhibitor of the PLD cofactor ADP-ribosylation factor, and in cells infected with retrovirus containing PLD(2) siRNA or transfected with PLD(2) antisense but not control LacZ or sense oligonucleotide. Diacylglycerol kinase inhibitor II diminished Ang II-induced and diC8-phosphatidic acid (PA)-increased Akt phosphorylation, suggesting that PLD-dependent Akt activation is mediated by PA. Ang II-induced EGFR phosphorylation was inhibited by 1-butanol and PLD(2) siRNA and also by cPLA(2) siRNA. In addition, the inhibitor of arachidonic acid (AA) metabolism 5,8,11,14-eicosatetraynoic acid (ETYA) reduced both Ang II- and AA-induced EGFR transactivation. Furthermore, ETYA, cPLA(2) antisense, and cPLA(2) siRNA attenuated Ang II-elicited PLD activation. p38 MAPK inhibitor SB202190 [4-(4-flurophenyl)-2-(4-hydroxyphenyl)-5-(4-pyridyl)1H-imidazole] reduced PLD activity and EGFR and Akt phosphorylation elicited by Ang II. Pyrrolidine-1, a cPLA(2) inhibitor, and cPLA(2) siRNA decreased p38 MAPK activity. These data indicate that Ang II-stimulated Akt activity is mediated by cPLA(2)-dependent, p38 MAPK regulated PLD(2) activation and EGFR transactivation. We propose the following scheme of the sequence of events leading to activation of Akt in VSMC by Ang II: Ang II-->cPLA(2)-->AA-->p38 MAPK-->PLD(2)-->PA-->EGFR-->Akt. PMID:15525798

  12. Multiple human isoforms of drug transporters contribute to the hepatic and renal transport of olmesartan, a selective antagonist of the angiotensin II AT1-receptor.

    Science.gov (United States)

    Yamada, Akihiro; Maeda, Kazuya; Kamiyama, Emi; Sugiyama, Daisuke; Kondo, Tsunenori; Shiroyanagi, Yoshiyuki; Nakazawa, Hayakazu; Okano, Teruo; Adachi, Masashi; Schuetz, John D; Adachi, Yasuhisa; Hu, Zhuohan; Kusuhara, Hiroyuki; Sugiyama, Yuichi

    2007-12-01

    Olmesartan, a novel angiotensin II AT1-receptor antagonist, is excreted into both bile and urine, with minimal metabolism. Because olmesartan is a hydrophilic anionic compound, some transporters could be involved in its hepatic and renal clearance. In this study, we characterized the role of human drug transporters in the pharmacokinetics of olmesartan and determined the contribution of each transporter to the overall clearance of olmesartan. Olmesartan was significantly taken up into human embryonic kidney 293 cells expressing organic anion-transporting polypeptide (OATP) 1B1, OATP1B3, organic anion transporter (OAT) 1, and OAT3. We also observed its saturable uptake into human hepatocytes and kidney slices. Estimated from the relative activity factor method and application of specific inhibitors, the relative contributions of OATP1B1 and OATP1B3 to the uptake of olmesartan in human hepatocytes were almost the same, whereas OAT3 was predominantly involved in its uptake in kidney slices. The vectorial transport of olmesartan was observed in OATP1B1/multidrug resistance-associated protein (MRP) 2 double transfectants, but not in OATP1B1/multidrug resistance (MDR) 1 and OATP1B1/breast cancer resistance protein (BCRP) transfectants. ATP-dependent transport into membrane vesicles expressing human MRP2 and MRP4 was clearly observed, with K(m) values of 14.9 and 26.2 microM, respectively, whereas the urinary excretion of olmesartan in Mrp4-knockout mice was not different from that of control mice. We also investigated the transcellular transport of olmesartan medoxomil, a prodrug of olmesartan. Vectorial basal-to-apical transport was observed in OATP1B1/MRP2, OATP1B1/MDR1 double, and OATP1B1/BCRP double transfectants, suggesting the possible involvement of MRP2, MDR1, and BCRP in the limit of intestinal absorption of olmesartan medoxomil. From these results, we suggest that multiple transporters make a significant contribution to the pharmacokinetics of olmesartan and

  13. Angiotensin Converting Enzyme Gene I/D Polymorphism in Pakistani Rheumatic Heart Disease Patients and Healthy Controls

    Directory of Open Access Journals (Sweden)

    Sadia Rehman

    2015-09-01

    Full Text Available Background: Valve scarring and collagen deposition are crucial in pathogenesis of Rheumatic Heart Disease (RHD, an autoimmune disorder of the heart. Angiotensin I-Converting Enzyme (ACE plays a major role in fibrous tissue formation. Objectives: The present research work aimed to assess the role of ACE Insertion/Deletion (I/D polymorphism in progress of RHD. Patients and Methods: DNA was pre pared from blood samples from 156 RHD patients (156 and 204 healthy ethnically-matched controls. Then, it was screened using sequence-specific Primers. Polymerase chain reaction and Agarose gel electrophoresis. The data were analyzed using Vassar stats (http://faculty.vassar.edu/lowry/VassarStats.html. Results: I allele (P = 0.024, OR = 1.42 and II genotype (P = 0.001, OR = 3.07 were significantly higher in Pakistani RHD patients compared to the healthy controls. Also, a significant difference was found between the female, but not male, patients and the controls regarding I allele and II genotype. Conclusions: The study results provided information about involvement of ACE I/D polymorphism in molecular mechanism of RHD. Thus, it can become one of the useful tools in risk assessment and help with designing strategies to combat the disease.

  14. Common promoter elements in odorant and vomeronasal receptor genes.

    Directory of Open Access Journals (Sweden)

    Jussara S Michaloski

    Full Text Available In mammals, odorants and pheromones are detected by hundreds of odorant receptors (ORs and vomeronasal receptors (V1Rs and V2Rs expressed by sensory neurons that are respectively located in the main olfactory epithelium and in the vomeronasal organ. Even though these two olfactory systems are functionally and anatomically separate, their sensory neurons show a common mechanism of receptor gene regulation: each neuron expresses a single receptor gene from a single allele. The mechanisms underlying OR and VR gene expression remain unclear. Here we investigated if OR and V1R genes share common sequences in their promoter regions.We conducted a comparative analysis of promoter regions of 39 mouse V1R genes and found motifs that are common to a large number of promoters. We then searched mouse OR promoter regions for motifs that resemble the ones found in the V1R promoters. We identified motifs that are present in both the V1R and OR promoter regions. Some of these motifs correspond to the known O/E like binding sites while others resemble binding sites for transcriptional repressors. We show that one of these motifs specifically interacts with proteins extracted from both nuclei from olfactory and vomeronasal neurons. Our study is the first to identify motifs that resemble binding sites for repressors in the promoters of OR and V1R genes. Analysis of these motifs and of the proteins that bind to these motifs should reveal important aspects of the mechanisms of OR/V1R gene regulation.

  15. Pulmonary Embolism in a Sarcoidosis Patient Double Heterozygous for Methylenetetrahydrofolate Reductase Gene Polymorphisms and Factor V Leiden and Homozygous for the D-Allele of Angiotensin Converting Enzyme Gene

    Directory of Open Access Journals (Sweden)

    Nadim El-Majzoub

    2015-01-01

    Full Text Available Sarcoidosis is a multisystem granulomatous disease of unknown etiology and pathogenesis. It presents in patients younger than 40 years of age. The lungs are the most commonly affected organ. Till the present day, there is no single specific test that will accurately diagnose sarcoidosis; as a result, the diagnosis of sarcoidosis relies on a combination of clinical, radiologic, and histologic findings. Patients with sarcoidosis have been found to have an increased risk of pulmonary embolism compared to the normal population. MTHFR and factor V Leiden mutations have been reported to increase the risk of thrombosis in patients. We hereby present a case of a middle aged man with sarcoidosis who developed a right main pulmonary embolism and was found to be double heterozygous for methylenetetrahydrofolate reductase gene polymorphisms and factor V Leiden and homozygous for the D-allele of the angiotensin converting enzyme gene.

  16. Angiotensin II Type 1 receptor (AT1) signaling in astrocytes regulates synaptic degeneration-induced leukocyte entry to the central nervous system

    DEFF Research Database (Denmark)

    Füchtbauer, L; Groth-Rasmussen, Maria; Holm, Thomas Hellesøe; Løbner, M; Toft-Hansen, Henrik; Khorooshi, Reza M. H.; Owens, T

    2011-01-01

    the dentate gyrus following axonal transection was totally abrogated in GFAP-IκBα-dn mice. Whereas angiotensin II was upregulated in microglia and astrocytes in the dentate gyrus post-lesion, AT1 was exclusively expressed on astrocytes. Blocking AT1 with Candesartan led to significant increase in...

  17. Addition of ETA receptor blockade increases renoprotection provided by renin-angiotensin system blockade in 5/6 nephrectomized Ren-2 transgenic rats

    Czech Academy of Sciences Publication Activity Database

    Čertíková; Chábová, V.; Vernerová, Z.; Kujal, P.; Husková, Z.; Škaroupková, P.; Tesař, V.; Kramer, H. J.; Kompanowska; Jezierska, E.; Walkowska, A.; Sadowski, J.; Červenka, L.; Vaněčková, Ivana

    2014-01-01

    Roč. 118, č. 2 (2014), s. 297-305. ISSN 0024-3205 R&D Projects: GA ČR(CZ) GAP304/12/0259 Institutional support: RVO:67985823 Keywords : renal failure * 5/6 nephrectomy * renin-angiotensin * endothelin * survival Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 2.702, year: 2014

  18. Gene specific actions of thyroid hormone receptor subtypes.

    Directory of Open Access Journals (Sweden)

    Jean Z Lin

    Full Text Available There are two homologous thyroid hormone (TH receptors (TRs α and β, which are members of the nuclear hormone receptor (NR family. While TRs regulate different processes in vivo and other highly related NRs regulate distinct gene sets, initial studies of TR action revealed near complete overlaps in their actions at the level of individual genes. Here, we assessed the extent that TRα and TRβ differ in target gene regulation by comparing effects of equal levels of stably expressed exogenous TRs +/- T(3 in two cell backgrounds (HepG2 and HeLa. We find that hundreds of genes respond to T(3 or to unliganded TRs in both cell types, but were not able to detect verifiable examples of completely TR subtype-specific gene regulation. TR actions are, however, far from identical and we detect TR subtype-specific effects on global T(3 response kinetics in HepG2 cells and many examples of TR subtype specificity at the level of individual genes, including effects on magnitude of response to TR +/- T(3, TR regulation patterns and T(3 dose response. Cycloheximide (CHX treatment confirms that at least some differential effects involve verifiable direct TR target genes. TR subtype/gene-specific effects emerge in the context of widespread variation in target gene response and we suggest that gene-selective effects on mechanism of TR action highlight differences in TR subtype function that emerge in the environment of specific genes. We propose that differential TR actions could influence physiologic and pharmacologic responses to THs and selective TR modulators (STRMs.

  19. CRDB: database of chemosensory receptor gene families in vertebrate.

    Directory of Open Access Journals (Sweden)

    Dong Dong

    Full Text Available Chemosensory receptors (CR are crucial for animals to sense the environmental changes and survive on earth. The emergence of whole-genome sequences provides us an opportunity to identify the entire CR gene repertoires. To completely gain more insight into the evolution of CR genes in vertebrates, we identified the nearly all CR genes in 25 vertebrates using homology-based approaches. Among these CR gene repertoires, nearly half of them were identified for the first time in those previously uncharacterized species, such as the guinea pig, giant panda and elephant, etc. Consistent with previous findings, we found that the numbers of CR genes vary extensively among different species, suggesting an extreme form of 'birth-and-death' evolution. For the purpose of facilitating CR gene analysis, we constructed a database with the goals to provide a resource for CR genes annotation and a web tool for exploring their evolutionary patterns. Besides a search engine for the gene extraction from a specific chromosome region, an easy-to-use phylogenetic analysis tool was also provided to facilitate online phylogeny study of CR genes. Our work can provide a rigorous platform for further study on the evolution of CR genes in vertebrates.

  20. CRDB: database of chemosensory receptor gene families in vertebrate.

    Science.gov (United States)

    Dong, Dong; Jin, Ke; Wu, Xiaoli; Zhong, Yang

    2012-01-01

    Chemosensory receptors (CR) are crucial for animals to sense the environmental changes and survive on earth. The emergence of whole-genome sequences provides us an opportunity to identify the entire CR gene repertoires. To completely gain more insight into the evolution of CR genes in vertebrates, we identified the nearly all CR genes in 25 vertebrates using homology-based approaches. Among these CR gene repertoires, nearly half of them were identified for the first time in those previously uncharacterized species, such as the guinea pig, giant panda and elephant, etc. Consistent with previous findings, we found that the numbers of CR genes vary extensively among different species, suggesting an extreme form of 'birth-and-death' evolution. For the purpose of facilitating CR gene analysis, we constructed a database with the goals to provide a resource for CR genes annotation and a web tool for exploring their evolutionary patterns. Besides a search engine for the gene extraction from a specific chromosome region, an easy-to-use phylogenetic analysis tool was also provided to facilitate online phylogeny study of CR genes. Our work can provide a rigorous platform for further study on the evolution of CR genes in vertebrates. PMID:22393364

  1. Gene Expression Control by Glucocorticoid Receptors during Innate Immune Responses

    Directory of Open Access Journals (Sweden)

    André M. Xavier

    2016-04-01

    Full Text Available Glucocorticoids (GCs are potent anti-inflammatory compounds that have been extensively used in clinical practice for several decades. GCs effects on inflammation are generally mediated through GC receptors (GRs. Signal transduction through these nuclear receptors leads to dramatic changes in gene expression programs in different cell types, typically due to GR binding to DNA or to transcription modulators. During the last decade the view of GCs as exclusive anti-inflammatory molecules has been challenged. GR negative interference in pro-inflammatory gene expression was a landmark in terms of molecular mechanisms that suppress immune activity. In fact, GR can induce varied inhibitory molecules, including a negative regulator of Toll-like receptors (TLRs pathway, or subject key transcription factors, such as NF-B and AP-1, to a repressor mechanism. In contrast, the expression of some acute-phase proteins (APPs and other players of innate immunity generally requires GR signaling. Consequently, GRs must operate context-dependent inhibitory, permissive or stimulatory effects on host defense signaling triggered by pathogens or tissue damage. This review aims to disclose how contradictory or comparable effects on inflammatory gene expression can depend on pharmacological approach (including selective glucocorticoid receptor modulators; SEGRMs, cell culture, animal treatment or transgenic strategies used as models. Although the current view of GR-signaling integrated many advances in the field, some answers to important questions remain elusive.

  2. Gene Expression Control by Glucocorticoid Receptors during Innate Immune Responses

    Science.gov (United States)

    Xavier, Andre Machado; Anunciato, Aparecida Kataryna Olimpio; Rosenstock, Tatiana Rosado; Glezer, Isaias

    2016-01-01

    Glucocorticoids (GCs) are potent anti-inflammatory compounds that have been extensively used in clinical practice for several decades. GC’s effects on inflammation are generally mediated through GC receptors (GRs). Signal transduction through these nuclear receptors leads to dramatic changes in gene expression programs in different cell types, typically due to GR binding to DNA or to transcription modulators. During the last decade, the view of GCs as exclusive anti-inflammatory molecules has been challenged. GR negative interference in pro-inflammatory gene expression was a landmark in terms of molecular mechanisms that suppress immune activity. In fact, GR can induce varied inhibitory molecules, including a negative regulator of Toll-like receptors pathway, or subject key transcription factors, such as NF-κB and AP-1, to a repressor mechanism. In contrast, the expression of some acute-phase proteins and other players of innate immunity generally requires GR signaling. Consequently, GRs must operate context-dependent inhibitory, permissive, or stimulatory effects on host defense signaling triggered by pathogens or tissue damage. This review aims to disclose how contradictory or comparable effects on inflammatory gene expression can depend on pharmacological approach (including selective GC receptor modulators; SEGRMs), cell culture, animal treatment, or transgenic strategies used as models. Although the current view of GR-signaling integrated many advances in the field, some answers to important questions remain elusive. PMID:27148162

  3. Association between angiotensin converting enzyme gene insertion/deletion polymorphism and renal scar risk in children vesicoureteral reflex: a reappraise meta-analysis

    Science.gov (United States)

    Ai, Jin-Wei; Zeng, Xian-Tao; Liu, Ying; Fu, Yu; Liu, Tong-Zu; Pei, Bin

    2016-01-01

    Vesicoureteral reflex(VUR) is a common disease in children. Some studies indicated that the angiotensin converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism associated with the renal scar in VUR, but not all researchers agreed with it. To clarify the effect of ACE I/D polymorphism on renal scar risk in children with VUR, we performed the present meta-analysis. PubMed, CNKI, CBM, and Embase databases were searched for studies that examined the relationship between ACE I/D polymorphism and renal scar risk in children with VUR. The Stata 12.0 software was used for statistical analyses. 11 case-control studies with 1,032 VUR patients were analyzed. The results showed that the DD genotype and D allele were associated with renal scar risk in overall VUR patients, DD vs. DI + II: OR = 1.61, 95% CI = 1.04–2.49, P = 0.03; DD vs. II: OR = 1.78, 95% CI = 1.20–2.65, P < 0.01; D vs. I: OR = 1.38, 95% CI = 1.02–1.86, P = 0.04. Similar results were revealed in Turks, but not in Caucasians and Asians. Our meta-analysis indicated that the ACE DD genotype may increase the risk of renal scar in children with VUR. PMID:27506878

  4. Altered expression of renal bumetanide-sensitive sodium-pota-ssium-2 chloride cotransporter and Cl- channel -K2 gene in angiotensin Ⅱ-infused hypertensive rats

    Institute of Scientific and Technical Information of China (English)

    YE Tao; LIU Zhi-quan; SUN Chao-feng; ZHENG Yong; MA Ai-qun; FANG Yuan

    2005-01-01

    Background Little information is available regarding the effect of angiotensin Ⅱ (Ang Ⅱ) on the bumetanide-sensitive sodium-potassium-2 chloride cotransporter (NKCC2), the thiazide-sensitive sodium-chloride cotransporter (NCC), and the Cl- channel (CLC)-K2 at both mRNA and protein expression level in Ang Ⅱ-induced hypertensive rats. This study was conducted to investigate the influence of Ang Ⅱ with chronic subpressor infusion on nephron-specific gene expression of NKCC2, NCC and CLC-K2. Results Ang Ⅱ significantly increased blood pressure and up-regulated NKCC2 mRNA and protein expression in the kidney. Expression of CLC-K2 mRNA in the kidney increased 1.6 fold (P<0.05).There were no changes in NCC mRNA or protein expression in AngII-treated rats versus control. Conclusions Chronic subpressor Ang Ⅱ infusion can significantly alter NKCC2 and CLC-K2 mRNA expression in the kidney, and protein abundance of NKCC2 in kidney is positively regulated by Ang Ⅱ. These effects may contribute to enhanced renal Na+ and Cl- reabsorption in response to Ang Ⅱ.

  5. Between-patient differences in the renal response to renin-angiotensin system intervention: clue to optimising renoprotective therapy?

    NARCIS (Netherlands)

    Laverman, Ger Jan; Navis, Ger Jan; de Zeeuw, Dick

    2002-01-01

    Renin-angiotensin-aldosterone system (RAAS) blockade with angiotensin-converting enzyme inhibitors (ACE-I) or angiotensin II (Ang II), AT(1)-receptor blockers (ARB) is the cornerstone of renoprotective therapy. Still, the number of patients with end-stage renal disease is increasing worldwide, promp

  6. Between-patient differences in the renal response to renin-angiotensin system intervention : clue to optimising renoprotective therapy?

    NARCIS (Netherlands)

    Laverman, GD; de Zeeuw, D; Navis, G

    2002-01-01

    Renin-angiotensin-aldosterone system (RAAS) blockade with angiotensin-converting enzyme inhibitors (ACE-I) or angiotensin II (Ang II), AT(1)-receptor blockers (ARB) is the cornerstone of renoprotective therapy. Still, the number of patients with end-stage renal disease is increasing worldwide, promp

  7. Effects of Qindan Capsule(芩丹胶囊) on Blood Pressure,Endothelin, Calcitonin Gene-related Peptide and Angiotensin-Ⅱ in Spontaneous Hypertensive Rats

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Objective: To observe the hypotensive effects of Qindan Capsule (芩丹胶囊, QC) on spontaneous hypertensive rats (SHR) and its effect on the contents of endothelin (ET), calcitonin gene-related peptide (CGRP) and angiotensin-Ⅱ (Ang-Ⅱ ) in plasma and vascular tissues, and to investigate the possible mechanism of QC in lowering blood pressure. Methods: Forty SHRs were divided into 5 groups: the high dosage QC group [QCHD, 750 mg/(kg·d)], the low dosage QC group [QCLD, 150 mg/(kg·d)], the Niuhuang Jiangya Pill group [牛黄降压丸, NJP, 200 mg/(kg·d)], the Captopril group [ 15 mg/(kg·d)]and the model group, 8 in each group. Meanwhile, a normal control group consisting of 8 Wistar-Kyoto (WKY) rats was set up also. All the rats were administered with medicine through gastrogavage. Systolic blood pressure (SBP),level of ET, CGRP and Ang-Ⅱ in plasma and Ang-Ⅱ in tissues of mesenteric artery were detected in all the rats after 12 weeks of treatment. Results: The level of SBP after treatment in the QCHD group was lower than that in the model group ( P<0.01 ), but with no significant difference as compared with that in the Captopril group and the NJP group (P>0.05). After treatment, the plasma level of ET was lower and CGRP higher than those in the model group (both P<0.05), and also higher than those in the NJP and Captopril group (both P<0.05). As for the content of Ang- Ⅱ, in mesenteric arterial tissues, it was lower in the QCHD group than that in the model group ( P<0.05), but in plasma, it showed no significant difference between the two groups (P>0.05). Conclusion: QC has a satisfactory hypotensive action on SHR rats, and its mechanism may be associated with the regulation on plasma vasoactive peptide and regional renin-angiotensin system.

  8. Intrarenal alterations of the angiotensin-converting enzyme type 2/angiotensin 1-7 complex of the renin-angiotensin system do not alter the course of malignant hypertension in Cyp1a1-Ren-2 transgenic rats.

    Science.gov (United States)

    Husková, Zuzana; Kopkan, Libor; Červenková, Lenka; Doleželová, Šárka; Vaňourková, Zdeňka; Škaroupková, Petra; Nishiyama, Akira; Kompanowska-Jezierska, Elzbieta; Sadowski, Janusz; Kramer, Herbert J; Červenka, Luděk

    2016-04-01

    The role of the intrarenal renin-angiotensin system (RAS) in the pathophysiology of malignant hypertension is not fully understood. Accumulating evidence indicates that the recently discovered vasodilator axis of the RAS, angiotensin-converting enzyme (ACE) type 2 (ACE2)/angiotensin 1-7 (ANG 1-7), constitutes an endogenous system counterbalancing the hypertensiogenic axis, ACE/angiotensin II (ANG II)/AT1 receptor. This study aimed to evaluate the role of the intrarenal vasodilator RAS axis in the pathophysiology of ANG II-dependent malignant hypertension in Cyp1a1-Ren-2 transgenic rats. ANG II-dependent malignant hypertension was induced by 13 days' dietary administration of indole-3-carbinol (I3C), a natural xenobiotic that activates the mouse renin gene in Cyp1a1-Ren-2 transgenic rats. It was hypothesized that pharmacologically-induced inhibition of the ACE2/ANG 1-7 complex should aggravate, and activation of this axis should attenuate, the course of ANG II-dependent malignant hypertension. Blood pressure (BP) was monitored by radiotelemetry. ACE2 inhibitor (DX 600, 0.2 μg/day) and ACE2 activator (DIZE, 1 mg/day) were administrated via osmotic minipumps. Even though ACE2 inhibitor significantly decreased and ACE2 activator increased intrarenal ANG 1-7 concentrations, the course of BP, as well as of albuminuria, cardiac hypertrophy and renal glomerular damage, were not altered. It was shown that intrarenal alterations in the ACE2/ANG 1-7 complex did not significantly modify the course of malignant hypertension in I3C-induced Cyp1a1-Ren-2 transgenic rats. Thus, in our experimental setting alterations of this intrarenal vasodilator complex of the RAS do not significantly modify the form of malignant hypertension that clearly depends on the inappropriately increased activity of the ACE/ANG II/AT1 receptor axis. PMID:26833491

  9. ACACβ gene (rs2268388) and AGTR1 gene (rs5186) polymorphism and the risk of nephropathy in Asian Indian patients with type 2 diabetes

    DEFF Research Database (Denmark)

    Shah, Viral N; Cheema, Balneek Singh; Sharma, Rajni; Khullar, Madhu; Kohli, Harbir Singh; Ahluwalia, Tarun Veer Singh; Mohan, Viswanathan; Bhansali, Anil

    Patients with type 2 diabetes (T2DM) are usually obese and concurrent obesity results into activation of the renin-angiotensin-system (RAS) which is a risk factor for diabetic nephropathy (DN). Gene-gene interaction between acetyl-coenzymeA carboxylase beta (ACACβ) gene, which is involved in fatty...... acid metabolism and angiotensin II receptors (AGTR1) gene, which mediates RAS proteins actions on renal tissue, polymorphism with DN have not been studied earlier. The present study was designed with the aim to examine the association of an ACACβ (rs2268388) and AGTR1 (rs5186) gene polymorphism with...

  10. The Role of Metabotropic Glutamate Receptor Genes in Schizophrenia.

    Science.gov (United States)

    Maj, Carlo; Minelli, Alessandra; Giacopuzzi, Edoardo; Sacchetti, Emilio; Gennarelli, Massimo

    2016-01-01

    Genomic studies revealed two main components in the genetic architecture of schizophrenia, one constituted by common variants determining a distributed polygenic effect and one represented by a large number of heterogeneous rare and highly disruptive mutations. These gene modifications often affect neural transmission and different studies proved an involvement of metabotropic glutamate receptors in schizophrenia phenotype. Through the combination of literature information with genomic data from public repositories, we analyzed the current knowledge on the involvement of genetic variations of the human metabotropic glutamate receptors in schizophrenia and related endophenotypes. Despite the analysis did not reveal a definitive connection, different suggestive associations have been identified and in particular a relevant role has emerged for GRM3 in affecting specific schizophrenia endophenotypes. This supports the hypothesis that these receptors are directly involved in schizophrenia disorder. PMID:27296644

  11. Additive effects of cilnidipine, an L-/N-type calcium channel blocker, and an angiotensin II receptor blocker on reducing cardiorenal damage in Otsuka Long-Evans Tokushima Fatty rats with type 2 diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Mori Y

    2014-06-01

    Full Text Available Yutaka Mori,1,2 Shizuka Aritomi,3 Kazumi Niinuma,3 Tarou Nakamura,3 Kenichi Matsuura,1 Junichi Yokoyama,1 Kazunori Utsunomiya1 1Division of Diabetes and Endocrinology, Department of Internal Medicine, The Jikei University School of Medicine, Minato-ku, Japan; 2Department of Clinical Research, National Hospital Organization, Utsunomiya National Hospital, Utsunomiya, Japan; 3Research Center, Ajinomoto Pharmaceuticals Co, Ltd, Kanagawa, Japan Abstract: Cilnidipine (Cil, which is an L-/N-type calcium channel blocker (CCB, has been known to provide renal protection by decreasing the activity of the sympathetic nervous system (SNS and the renin–angiotensin system. In this study, we compared the effects of the combination of Cil and amlodipine (Aml, which is an L-type CCB, with an angiotensin (Ang II receptor blocker on diabetic cardiorenal damage in spontaneously type 2 diabetic rats. Seventeen-week-old Otsuka Long-Evans Tokushima Fatty rats were randomly assigned to receive Cil, Aml, valsartan (Val, Cil + Val, Aml + Val, or a vehicle (eight rats per group for 22 weeks. Antihypertensive potencies were nearly equal among the CCB monotherapy groups and the combination therapy groups. The lowering of blood pressure by either treatment did not significantly affect the glycemic variables. However, exacerbations of renal and heart failure were significantly suppressed in rats administered Cil or Val, and additional suppression was observed in those administered Cil + Val. Although Val increased the renin–Ang system, Aml + Val treatment resulted in additional increases in these parameters, while Cil + Val did not show such effects. Furthermore, Cil increased the ratio of Ang-(1–7 to Ang-I, despite the fact that Val and Aml + Val decreased the Ang-(1–7 levels. These actions of Cil + Val might be due to their synergistic inhibitory effect on the activity of the SNS, and on aldosterone secretion through N-type calcium channel antagonism and Ang II

  12. Value of Angiotensin-Converting Enzyme and Monoxide Nitrogen in Pathogenesis of Myocardium Remodeling Depending on Genes' Polymorphism of Асе (I/D) and eNOS (894T>G) in Patients with Arterial Hypertension

    OpenAIRE

    Sydorchuk L.P.; Gaborec I.Y.; Sydorchuk A.R.; Bukach O.P.; Sokolenko A.A.; Ursuliak J.V.; Ivaschuk S.I.; Antoniuk M.V.; Yarynych J.M.

    2013-01-01

    Introduction: Humans genes mutations in altered social conditions through interaction with environmental factors and harmful habits become an individual risk factor. Objectives: To evaluate Angiotensin-Converting Enzyme (ACE) and nitrogen monoxide metabolites (NO/NO2-/NO3-) blood levels depending on I/D polymorphism of ACE gene (dbSNP id:rs4646994), 894T>G of Endothelial Nitric Oxide Synthase (eNOS, dbSNP id:rs1799983) in pathogenesis of left ventricular hypertrophy (LVH) in patients with Ess...

  13. Analysis of the apo E/apo C-I, angiotensin converting enzyme and methylenetetrahydrofolate reductase genes as candidates affecting human longevity.

    Science.gov (United States)

    Galinsky, D; Tysoe, C; Brayne, C E; Easton, D F; Huppert, F A; Dening, T R; Paykel, E S; Rubinsztein, D C

    1997-03-21

    Genetic factors are likely to affect human survival, since twin studies have shown greater concordance for age of death in monozygotic compared to dizygotic twins. Coronary artery disease is an important contributor to premature mortality in the UK. Accordingly, we have chosen genes associated with cardiovascular risk, apo E/apo C-I, angiotensin converting enzyme (ACE) and methylenetetrahydrofolate reductase (MTHFR), as candidates which may affect longevity/survival into old age. An association study was performed by comparing allele and genotype frequencies at polymorphic loci associated with these genes in 182 women and 100 men aged 84 years and older with 100 boys and 100 girls younger than 17 years. MTHFR allele and genotype frequencies were similar in the elderly and young populations. Apo C-I allele and genotype frequencies were significantly different in the elderly women compared to the younger sample (P Hardy-Weinberg equilibrium and compared to observed genotypes in elderly men and women. In contrast to previous studies, apo E2 was not overrepresented in the elderly men or women. Thus, the proposition that apo E2, E3 and E4 protein isoforms are themselves functionally associated with increasing risks for early death, may be too simplistic. The I/I ACE was depleted in the elderly males but not the elderly females. Furthermore, significant differences were observed between ACE genotypes in elderly men and elderly women. These data suggest that the penetrance of loci which influence survival may vary according to sex. The depletion of the ACE I/I genotype in elderly men is generally consistent with a previous study which found decreased frequencies of the I allele in French centenarians compared to younger controls. However, these results are apparently paradoxical, since others have suggested that the I allele is associated with increased cardiovascular risk. Clarification of the overall effect of a genotype on survival will be vital if therapies are to be

  14. Comparative effects of contraction and angiotensin II on growth of adult feline cardiocytes in primary culture

    Science.gov (United States)

    Wada, H.; Zile, M. R.; Ivester, C. T.; Cooper, G. 4th; McDermott, P. J.

    1996-01-01

    The purposes of this study were 1) to determine whether angiotensin II causes growth of adult feline cardiocytes in long-term culture, 2) to compare the growth effects of angiotensin II with those resulting from electrically stimulated contraction, and 3) to determine whether the anabolic effects of contraction are exerted via the angiotensin type 1 receptor. Adult feline cardiocytes were cultured on laminin-coated trays in a serum-free medium. Cardiocytes were either electrically stimulated to contract (1 Hz, 5-ms pulse duration, alternating polarity) or were nonstimulated and quiescent. Quiescent cells were studied as controls and after treatment with angiotensin II (10(-8) M), losartan (10(-6) M; an angiotensin type 1-receptor antagonist), or angiotensin II plus losartan. Contracting cells were studied in the presence and absence of angiotensin II or losartan. In quiescent cardiocytes, angiotensin II treatment on day 7 significantly increased protein synthesis rates by 22% and protein content per cell by 17%. The effects of angiotensin II were completely blocked by losartan. Electrically stimulated contraction on days 4 and 7 in culture significantly increased protein synthesis rate by 18 and 38% and protein content per cell by 19 and 46%, respectively. Angiotensin II treatment did not further increase protein synthesis rate or protein content in contracting cardiocytes. Furthermore, losartan did not block the anabolic effects of contraction on protein synthesis rates or protein content. In conclusion, angiotensin II can exert a modest anabolic effect on adult feline cardiocytes in culture. In contracting feline cardiocytes, angiotensin II has no effect on growth. Growth caused by electrically stimulated contraction occurs more rapidly and is greater in magnitude than that caused by angiotensin II. Growth of contracting adult feline cardiocytes is not dependent on activation of the angiotensin receptor.

  15. Estrogenic receptors a and p gene polymorphisms in postmenopausal osteoporosis

    Directory of Open Access Journals (Sweden)

    K A Maslova

    2008-01-01

    Full Text Available Objective. To assess frequency distribution of estrogenic receptor (ERa and ERfl gene polymorphisms and their influence on bone mineral density (BMD in groups of postmenopausal women with and without osteoporosis (OP. Material and methods. 200 residents of Moscow and Moscow region were divided into two groups considering BMD values according to WHO criteria; OP group and healthy control group Results. Differences of genotype and their combinations frequency distribution between OP and control groups show presence OP risk and protector genotypes. ER gene important role in pathogenesis of postmenopausal osteoporosis and possibility to use these genetic markers for assessment of risk of OP development in Russian population was confirmed.

  16. First evidence for functional vomeronasal 2 receptor genes in primates

    OpenAIRE

    Hohenbrink, Philipp; Mundy, Nicholas I.; Zimmermann, Elke; Radespiel, Ute

    2013-01-01

    Two classes of vomeronasal receptor genes, V1R and V2R, occur in vertebrates. Whereas, V1R loci are found in a wide variety of mammals, including primates, intact V2R genes have thus far only been described in rodents and marsupials. In primates, the V2R repertoire has been considered degenerate. Here, we identify for the first time two intact V2R loci in a strepsirrhine primate, the grey mouse lemur (Microcebus murinus), and demonstrate their expression in the vomeronasal organ. Putatively f...

  17. Angiotensin-converting enzyme gene deletion polymorphism determines an increase in frequency of migraine attacks in patients suffering from migraine without aura.

    Science.gov (United States)

    Paterna, S; Di Pasquale, P; D'Angelo, A; Seidita, G; Tuttolomondo, A; Cardinale, A; Maniscalchi, T; Follone, G; Giubilato, A; Tarantello, M; Licata, G

    2000-01-01

    Many authors have reported an association between the angiotensin-converting enzyme (ACE)-D allele and coronary heart disease and other cardiovascular diseases. The mechanism underlying the positive associations between the ACE-D alleles and diseases are not yet clear. Previous reports showed an association between migraine without aura and ACE-D allele polymorphism. The study is aimed to evaluate if the DD genotype could also be associated with the frequency and duration of migraine without aura. In 302 patients suffering from migraine without aura (at least for 1 year), with no history of cardiovascular diseases and major risk factors for ischemic events, the genotypes of the ACE gene, plasma ACE activity, and the frequency (weekly) and duration of migraine attacks were evaluated. No drugs were given before (4 weeks) and during the study. The same evaluations were performed in 201 subjects without migraine. The molecular biologist and the physician evaluating the patient data were blinded to the clinical history and ACE-DD gene determination. Genotypes were determined by polymerase chain reaction amplification. Plasma ACE activity was performed by the HPLC method. The groups were similar for sex, age and smoking habit (migraines: 302 patients (200 F/102 M), mean age 37.8 +/- 8.2 years; control: 201 subjects (127 F/74 M), mean age 37.5 +/- 9.3 years). Patients with migraine without aura showed higher incidence of the ACE-DD gene (48.34%) than control subjects (37.32%), p < 0.05. The frequency of migraine (average attacks per week) was higher in patients with DD (2.11 +/- 1.9) than in patients with ID (1.54 +/- 1. 44), p < 0.05. No difference in duration of migraine attacks (hours per week) was observed. Plasma ACE activity was increased in patients with the ACE-DD gene. Our data suggest that ACE-DD gene polymorphism could have an important role in determining migraine attacks and the frequency of these attacks. Further data are needed through further studies

  18. Association of Interleukin-4 Receptor Gene Polymorphism with Chronic Periodontitis

    OpenAIRE

    M. Khoshhal; J. Moradi Haghgoo; Torkzaban, P.; S.R. Arabi; F. Vafaee; M. Hajiloie; B. Pourmoradi

    2011-01-01

    Introduction & Objective: Periodontitis is a multifactorial disease in which host immune system and genetic factors have an important role in its pathogenesis. Genetic polymorphisms in cytokines and their receptors have been proposed as potential markers for periodontal diseases. The aim of the present study was to evaluate whether IL-4R gene polymorphism is associated with chronic periodontitis (CP) or not? Materials & Methods: In this cross sectional study ninety non smoker patients (61 wom...

  19. Variant in oxytocin receptor gene is associated with amygdala volume

    OpenAIRE

    Furman, Daniella J; Chen, Michael C.; Gotlib, Ian H.

    2011-01-01

    The oxytocin system plays a significant role in modulating stress responses in animals and humans; perturbations in this system may contribute to the pathogenesis of psychiatric disorder. Attempts to identify clinically relevant genetic variants in the oxytocin system have yielded associations between polymorphisms of the oxytocin receptor (OXTR) gene and both autism and major depression. To date, however, little is known about how such variants affect brain structures implicated in these dis...

  20. Structure, characterization, and expression of the rat oxytocin receptor gene.

    OpenAIRE

    1995-01-01

    The multiple hormonal and neurotransmitter functions of the nonapeptide oxytocin are mediated by specific oxytocin receptors (OTRs). In most target tissues, the number of OTRs is strongly regulated. Specifically, in the uterus, a dramatic OTR upregulation precedes the onset of parturition. To study the molecular mechanisms underlying OTR regulation, we have isolated and characterized recombinant bacteriophage lambda EMBL3 genomic clones containing the rat OTR gene, using sequence information ...

  1. Mechanisms of oestrogen receptor (ER) gene regulation in breast cancer.

    Science.gov (United States)

    Carroll, J S

    2016-07-01

    Most breast cancers are driven by a transcription factor called oestrogen receptor (ER). Understanding the mechanisms of ER activity in breast cancer has been a major research interest and recent genomic advances have revealed extraordinary insights into how ER mediates gene transcription and what occurs during endocrine resistance. This review discusses our current understanding on ER activity, with an emphasis on several evolving, but important areas of ER biology. PMID:26884552

  2. Steroid/thyroid hormone receptor genes in Caenorhabditis elegans.

    OpenAIRE

    Kostrouch, Z; Kostrouchova, M; Rall, J. E.

    1995-01-01

    The large family of steroid/thyroid hormone receptor (STR) genes has been extensively studied in vertebrates and insects but little information is available on it in more primitive organisms. All members possess a DNA binding domain of zinc fingers of the C2, C2 type. We have used the polymerase chain reaction with degenerate oligonucleotide primers covering this region to clone three distinct members of this family from the nematode Caenorhabditis elegans. All three belong to the retinoic ac...

  3. Image-derived and arterial blood sampled input functions for quantitative PET imaging of the angiotensin II subtype 1 receptor in the kidney

    International Nuclear Information System (INIS)

    Purpose: The radioligand 11C-KR31173 has been introduced for positron emission tomography (PET) imaging of the angiotensin II subtype 1 receptor in the kidney in vivo. To study the biokinetics of 11C-KR31173 with a compartmental model, the input function is needed. Collection and analysis of arterial blood samples are the established approach to obtain the input function but they are not feasible in patients with renal diseases. The goal of this study was to develop a quantitative technique that can provide an accurate image-derived input function (ID-IF) to replace the conventional invasive arterial sampling and test the method in pigs with the goal of translation into human studies. Methods: The experimental animals were injected with [11C]KR31173 and scanned up to 90 min with dynamic PET. Arterial blood samples were collected for the artery derived input function (AD-IF) and used as a gold standard for ID-IF. Before PET, magnetic resonance angiography of the kidneys was obtained to provide the anatomical information required for derivation of the recovery coefficients in the abdominal aorta, a requirement for partial volume correction of the ID-IF. Different image reconstruction methods, filtered back projection (FBP) and ordered subset expectation maximization (OS-EM), were investigated for the best trade-off between bias and variance of the ID-IF. The effects of kidney uptakes on the quantitative accuracy of ID-IF were also studied. Biological variables such as red blood cell binding and radioligand metabolism were also taken into consideration. A single blood sample was used for calibration in the later phase of the input function. Results: In the first 2 min after injection, the OS-EM based ID-IF was found to be biased, and the bias was found to be induced by the kidney uptake. No such bias was found with the FBP based image reconstruction method. However, the OS-EM based image reconstruction was found to reduce variance in the subsequent phase of the ID

  4. Image-derived and arterial blood sampled input functions for quantitative PET imaging of the angiotensin II subtype 1 receptor in the kidney

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Tao; Tsui, Benjamin M. W.; Li, Xin; Vranesic, Melin; Lodge, Martin A.; Gulaldi, Nedim C. M.; Szabo, Zsolt, E-mail: zszabo@jhmi.edu [Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins School of Medicine, Baltimore, Maryland 21287 (United States)

    2015-11-15

    Purpose: The radioligand {sup 11}C-KR31173 has been introduced for positron emission tomography (PET) imaging of the angiotensin II subtype 1 receptor in the kidney in vivo. To study the biokinetics of {sup 11}C-KR31173 with a compartmental model, the input function is needed. Collection and analysis of arterial blood samples are the established approach to obtain the input function but they are not feasible in patients with renal diseases. The goal of this study was to develop a quantitative technique that can provide an accurate image-derived input function (ID-IF) to replace the conventional invasive arterial sampling and test the method in pigs with the goal of translation into human studies. Methods: The experimental animals were injected with [{sup 11}C]KR31173 and scanned up to 90 min with dynamic PET. Arterial blood samples were collected for the artery derived input function (AD-IF) and used as a gold standard for ID-IF. Before PET, magnetic resonance angiography of the kidneys was obtained to provide the anatomical information required for derivation of the recovery coefficients in the abdominal aorta, a requirement for partial volume correction of the ID-IF. Different image reconstruction methods, filtered back projection (FBP) and ordered subset expectation maximization (OS-EM), were investigated for the best trade-off between bias and variance of the ID-IF. The effects of kidney uptakes on the quantitative accuracy of ID-IF were also studied. Biological variables such as red blood cell binding and radioligand metabolism were also taken into consideration. A single blood sample was used for calibration in the later phase of the input function. Results: In the first 2 min after injection, the OS-EM based ID-IF was found to be biased, and the bias was found to be induced by the kidney uptake. No such bias was found with the FBP based image reconstruction method. However, the OS-EM based image reconstruction was found to reduce variance in the subsequent

  5. Genetic variation in angiotensin-converting enzyme 2 gene is associated with extent of left ventricular hypertrophy in hypertrophic cardiomyopathy

    OpenAIRE

    van der Merwe, Lize; Cloete, Ruben; Revera, Miriam; Heradien, Marshall; Goosen, Althea; Corfield, Valerie A.; Paul A Brink; Moolman-Smook, Johanna C

    2008-01-01

    Hypertrophic cardiomyopathy, a common, inherited cardiac muscle disease, is primarily caused by mutations in sarcomeric protein-encoding genes and is characterized by overgrowth of ventricular muscle that is highly variable in extent and location. This variability has been partially attributed to locus and allelic heterogeneity of the disease-causing gene, but other factors, including unknown genetic factors, also modulate the extent of hypertrophy that develops in response to the defective s...

  6. Inducible Knock-Down of the Mineralocorticoid Receptor in Mice Disturbs Regulation of the Renin-Angiotensin-Aldosterone System and Attenuates Heart Failure Induced by Pressure Overload.

    Directory of Open Access Journals (Sweden)

    Elena Montes-Cobos

    Full Text Available Mineralocorticoid receptor (MR inactivation in mice results in early postnatal lethality. Therefore we generated mice in which MR expression can be silenced during adulthood by administration of doxycycline (Dox. Using a lentiviral approach, we obtained two lines of transgenic mice harboring a construct that allows for regulatable MR inactivation by RNAi and concomitant expression of eGFP. MR mRNA levels in heart and kidney of inducible MR knock-down mice were unaltered in the absence of Dox, confirming the tightness of the system. In contrast, two weeks after Dox administration MR expression was significantly diminished in a variety of tissues. In the kidney, this resulted in lower mRNA levels of selected target genes, which was accompanied by strongly increased serum aldosterone and plasma renin levels as well as by elevated sodium excretion. In the healthy heart, gene expression and the amount of collagen were unchanged despite MR levels being significantly reduced. After transverse aortic constriction, however, cardiac hypertrophy and progressive heart failure were attenuated by MR silencing, fibrosis was unaffected and mRNA levels of a subset of genes reduced. Taken together, we believe that this mouse model is a useful tool to investigate the role of the MR in pathophysiological processes.

  7. Inducible Knock-Down of the Mineralocorticoid Receptor in Mice Disturbs Regulation of the Renin-Angiotensin-Aldosterone System and Attenuates Heart Failure Induced by Pressure Overload

    Science.gov (United States)

    Montes-Cobos, Elena; Li, Xiao; Fischer, Henrike J.; Sasse, André; Kügler, Sebastian; Didié, Michael; Toischer, Karl; Fassnacht, Martin; Dressel, Ralf; Reichardt, Holger M.

    2015-01-01

    Mineralocorticoid receptor (MR) inactivation in mice results in early postnatal lethality. Therefore we generated mice in which MR expression can be silenced during adulthood by administration of doxycycline (Dox). Using a lentiviral approach, we obtained two lines of transgenic mice harboring a construct that allows for regulatable MR inactivation by RNAi and concomitant expression of eGFP. MR mRNA levels in heart and kidney of inducible MR knock-down mice were unaltered in the absence of Dox, confirming the tightness of the system. In contrast, two weeks after Dox administration MR expression was significantly diminished in a variety of tissues. In the kidney, this resulted in lower mRNA levels of selected target genes, which was accompanied by strongly increased serum aldosterone and plasma renin levels as well as by elevated sodium excretion. In the healthy heart, gene expression and the amount of collagen were unchanged despite MR levels being significantly reduced. After transverse aortic constriction, however, cardiac hypertrophy and progressive heart failure were attenuated by MR silencing, fibrosis was unaffected and mRNA levels of a subset of genes reduced. Taken together, we believe that this mouse model is a useful tool to investigate the role of the MR in pathophysiological processes. PMID:26605921

  8. Toll-Like Receptor Gene Expression during Trichinella spiralis Infection.

    Science.gov (United States)

    Kim, Sin; Park, Mi Kyung; Yu, Hak Sun

    2015-08-01

    In Trichinella spiralis infection, type 2 helper T (Th2) cell-related and regulatory T (Treg) cell-related immune responses are the most important immune events. In order to clarify which Toll-like receptors (TLRs) are closely associated with these responses, we analyzed the expression of mouse TLR genes in the small intestine and muscle tissue during T. spiralis infection. In addition, the expression of several chemokine- and cytokine-encoding genes, which are related to Th2 and Treg cell mediated immune responses, were analyzed in mouse embryonic fibroblasts (MEFs) isolated from myeloid differentiation factor 88 (MyD88)/TIR-associated proteins (TIRAP) and Toll receptor-associated activator of interferons (TRIF) adapter protein deficient and wild type (WT) mice. The results showed significantly increased TLR4 and TLR9 gene expression in the small intestine after 2 weeks of T. spiralis infection. In the muscle, TLR1, TLR2, TLR5, and TLR9 gene expression significantly increased after 4 weeks of infection. Only the expression of the TLR4 and TLR9 genes was significantly elevated in WT MEF cells after treatment with excretory-secretory (ES) proteins. Gene expression for Th2 chemokine genes were highly enhanced by ES proteins in WT MEF cells, while this elevation was slightly reduced in MyD88/TIRAP(-/-) MEF cells, and quite substantially decreased in TRIF(-/-) MEF cells. In contrast, IL-10 and TGF-β expression levels were not elevated in MyD88/TIRAP(-/-) MEF cells. In conclusion, we suggest that TLR4 and TLR9 might be closely linked to Th2 cell and Treg cell mediated immune responses, although additional data are needed to convincingly prove this observation. PMID:26323841

  9. Behavioral meaningful opioidergic stimulation activates kappa receptor gene expression

    Directory of Open Access Journals (Sweden)

    E. Teodorov

    2012-10-01

    Full Text Available The periaqueductal gray (PAG has been reported to be a location for opioid regulation of pain and a potential site for behavioral selection in females. Opioid-mediated behavioral and physiological responses differ according to the activity of opioid receptor subtypes. The present study investigated the effects of the peripheral injection of the kappa-opioid receptor agonist U69593 into the dorsal subcutaneous region of animals on maternal behavior and on Oprk1 gene activity in the PAG of female rats. Female Wistar rats weighing 200-250 g at the beginning of the study were randomly divided into 2 groups for maternal behavior and gene expression experiments. On day 5, pups were removed at 7:00 am and placed in another home cage that was distant from their mother. Thirty minutes after removing the pups, the dams were treated with U69593 (0.15 mg/kg, sc or 0.9% saline (up to 1 mL/kg and after 30 min were evaluated in the maternal behavior test. Latencies in seconds for pup retrieval, grouping, crouching, and full maternal behavior were scored. The results showed that U69593 administration inhibited maternal behavior (P < 0.05 because a lower percentage of kappa group dams showed retrieval of first pup, retrieving all pups, grouping, crouching and displaying full maternal behavior compared to the saline group. Opioid gene expression was evaluated using real-time reverse-transcription polymerase chain reaction (RT-PCR. A single injection of U69593 increased Oprk1 PAG expression in both virgin (P < 0.05 and lactating female rats (P < 0.01, with no significant effect on Oprm1 or Oprd1 gene activity. Thus, the expression of kappa-opioid receptors in the PAG may be modulated by single opioid receptor stimulation and behavioral meaningful opioidergic transmission in the adult female might occur simultaneously to specific changes in gene expression of kappa-opioid receptor subtype. This is yet another alert for the complex role of the opioid system in

  10. Behavioral meaningful opioidergic stimulation activates kappa receptor gene expression

    International Nuclear Information System (INIS)

    The periaqueductal gray (PAG) has been reported to be a location for opioid regulation of pain and a potential site for behavioral selection in females. Opioid-mediated behavioral and physiological responses differ according to the activity of opioid receptor subtypes. The present study investigated the effects of the peripheral injection of the kappa-opioid receptor agonist U69593 into the dorsal subcutaneous region of animals on maternal behavior and on Oprk1 gene activity in the PAG of female rats. Female Wistar rats weighing 200-250 g at the beginning of the study were randomly divided into 2 groups for maternal behavior and gene expression experiments. On day 5, pups were removed at 7:00 am and placed in another home cage that was distant from their mother. Thirty minutes after removing the pups, the dams were treated with U69593 (0.15 mg/kg, sc) or 0.9% saline (up to 1 mL/kg) and after 30 min were evaluated in the maternal behavior test. Latencies in seconds for pup retrieval, grouping, crouching, and full maternal behavior were scored. The results showed that U69593 administration inhibited maternal behavior (P < 0.05) because a lower percentage of U69593 group dams showed retrieval of first pup, retrieving all pups, grouping, crouching and displaying full maternal behavior compared to the saline group. Opioid gene expression was evaluated using real-time reverse-transcription polymerase chain reaction (RT-PCR). A single injection of U69593 increased Oprk1 PAG expression in both virgin (P < 0.05) and lactating female rats (P < 0.01), with no significant effect on Oprm1 or Oprd1 gene activity. Thus, the expression of kappa-opioid receptors in the PAG may be modulated by single opioid receptor stimulation and behavioral meaningful opioidergic transmission in the adult female might occur simultaneously to specific changes in gene expression of kappa-opioid receptor subtype. This is yet another alert for the complex role of the opioid system in female

  11. Behavioral meaningful opioidergic stimulation activates kappa receptor gene expression

    Energy Technology Data Exchange (ETDEWEB)

    Teodorov, E. [Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, São Paulo, SP (Brazil); Ferrari, M.F.R. [Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, São Paulo, SP (Brazil); Fior-Chadi, D.R. [Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, São Paulo, SP (Brazil); Camarini, R. [Departamento de Farmacologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP (Brazil); Felício, L.F. [Departamento de Patologia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, SP (Brazil)

    2012-06-01

    The periaqueductal gray (PAG) has been reported to be a location for opioid regulation of pain and a potential site for behavioral selection in females. Opioid-mediated behavioral and physiological responses differ according to the activity of opioid receptor subtypes. The present study investigated the effects of the peripheral injection of the kappa-opioid receptor agonist U69593 into the dorsal subcutaneous region of animals on maternal behavior and on Oprk1 gene activity in the PAG of female rats. Female Wistar rats weighing 200-250 g at the beginning of the study were randomly divided into 2 groups for maternal behavior and gene expression experiments. On day 5, pups were removed at 7:00 am and placed in another home cage that was distant from their mother. Thirty minutes after removing the pups, the dams were treated with U69593 (0.15 mg/kg, sc) or 0.9% saline (up to 1 mL/kg) and after 30 min were evaluated in the maternal behavior test. Latencies in seconds for pup retrieval, grouping, crouching, and full maternal behavior were scored. The results showed that U69593 administration inhibited maternal behavior (P < 0.05) because a lower percentage of U69593 group dams showed retrieval of first pup, retrieving all pups, grouping, crouching and displaying full maternal behavior compared to the saline group. Opioid gene expression was evaluated using real-time reverse-transcription polymerase chain reaction (RT-PCR). A single injection of U69593 increased Oprk1 PAG expression in both virgin (P < 0.05) and lactating female rats (P < 0.01), with no significant effect on Oprm1 or Oprd1 gene activity. Thus, the expression of kappa-opioid receptors in the PAG may be modulated by single opioid receptor stimulation and behavioral meaningful opioidergic transmission in the adult female might occur simultaneously to specific changes in gene expression of kappa-opioid receptor subtype. This is yet another alert for the complex role of the opioid system in female

  12. Observations on the Evolution of the Melanocortin Receptor Gene Family: Distinctive Features of the Melanocortin-2 Receptor

    OpenAIRE

    RobertMichaelDores

    2013-01-01

    The melanocortin receptors are a gene family in the rhodopsin class of G protein-coupled receptors. Based on the analysis of several metazoan genome databases it appears that the melanocortin receptors are only found in chordates. The presence of five genes in the family (i.e., MC1R, MC2R, MC3R, MC4R, MC5R) in representatives of the tetrapods indicates that the gene family is the result of two genome duplication events and one local gene duplication event during the evolution of the chordates...

  13. Hypertension-Related Gene Polymorphisms of G-Protein-Coupled Receptor Kinase 4 Are Associated with NT-proBNP Concentration in Normotensive Healthy Adults

    Directory of Open Access Journals (Sweden)

    Junichi Yatabe

    2012-01-01

    Full Text Available G protein-coupled receptor kinase 4 (GRK4 with activating polymorphisms desensitize the natriuric renal tubular D1 dopamine receptor, and these GRK4 polymorphisms are strongly associated with salt sensitivity and hypertension. Meanwhile, N-terminal pro-B-type natriuretic peptide (NT-proBNP may be useful in detecting slight volume expansion. However, relations between hypertension-related gene polymorphisms including GRK4 and cardiovascular indices such as NT-proBNP are not clear, especially in healthy subjects. Therefore, various hypertension-related polymorphisms and cardiovascular indices were analyzed in 97 normotensive, healthy Japanese adults. NT-proBNP levels were significantly higher in subjects with two or more GRK4 polymorphic alleles. Other hypertension-related gene polymorphisms, such as those of renin-angiotensin-aldosterone system genes, did not correlate with NT-proBNP. There was no significant association between any of the hypertension-related gene polymorphisms and central systolic blood pressure, cardioankle vascular index, augmentation index, plasma aldosterone concentration, or an oxidative stress marker, urinary 8-OHdG. Normotensive individuals with GRK4 polymorphisms show increased serum NT-proBNP concentration and may be at a greater risk of developing hypertension and cardiovascular disease.

  14. Two polymorphisms in the glucocorticoid receptor gene directly affect glucocorticoid-regulated gene expression.

    NARCIS (Netherlands)

    H. Russcher (Henk); P. Smit (Pauline); E.L.T. van den Akker (Erica); E.F.C. van Rossum (Liesbeth); A.O. Brinkmann (Albert); F.H. de Jong (Frank); S.W.J. Lamberts (Steven); J.W. Koper (Jan)

    2005-01-01

    textabstractCONTEXT: Interindividual variation in glucocorticoid (GC)-sensitivity can be partly explained by polymorphisms in the GC receptor (GR) gene. The ER22/23EK and N363S polymorphisms have been described to be associated with lower and higher GC sensitivity, respectively. OBJECTIVE AND DESIGN

  15. Inhibition of the renin-angiotensin system for lowering coronary artery disease risk.

    Science.gov (United States)

    Sheppard, Richard J; Schiffrin, Ernesto L

    2013-04-01

    The renin-angiotensin system when activated exerts proliferative and pro-inflammatory actions and thereby contributes to progression of atherosclerosis, including that occurring in the coronary arteries. It thus contributes as well to coronary artery disease (CAD). Several clinical trials have examined effects of renin-angiotensin system inhibition for primary and secondary prevention of coronary heart disease. These include important trials such as HOPE, EUROPA and PEACE using angiotensin converting enzyme inhibitors, VALIANT, OPTIMAAL and TRANSCEND using angiotensin receptor blockers, and the ongoing TOPCAT study in patients with preserved ejection fraction heart failure, many of who also have coronary artery disease. Data are unavailable as yet of effects of either direct renin inhibitors or the new angiotensin receptor/neprilysin inhibitor agents. Today, inhibition of the renin-angiotensin system is standard-of-care therapy for lowering cardiovascular risk in secondary prevention in high cardiovascular risk subjects. PMID:23523606

  16. Intracellular insulin-receptor dissociation and segregation in a rat fibroblast cell line transfected with a human insulin receptor gene

    Energy Technology Data Exchange (ETDEWEB)

    Levy, J.R.; Olefsky, J.M.

    1988-05-05

    The cellular processing of insulin and insulin receptors was studied using a rat fibroblast cell line that had been transfected with a normal human insulin receptor gene, expressing approximately 500 times the normal number of native fibroblasts insulin receptors. These cells bind and internalize insulin normally. Biochemically assays based on the selective precipitation by polyethylene glycol of intact insulin-receptor complexes but not of free intracellular insulin were developed to study the time course of intracellular insulin-receptor dissociation. Fibroblasts were incubated with radiolabeled insulin at 4/sup 0/C, and internalization of insulin-receptor complexes was initiated by warming the cells to 37/sup 0/C. Within 2 min, 90% of the internalized radioactivity was composed of intact insulin-receptor complexes. The dissociation of insulin from internalized insulin-receptor complexes was markedly inhibited by monensin and chloroquine. Furthermore, chloroquine markedly increased the number of cross-linkable intracellular insulin-receptor complexes, as analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis autoradiography. These findings suggest that acidification of intracellular vesicles is responsible for insulin-receptor dissociation. Physical segregation of dissociated intracellular insulin from its receptor was monitored. The results are consistent with the view that segregation of insulin and receptor occurs 5-10 min after initiation of dissociation. These studies demonstrate the intracellular itinerary of insulin-receptor complexes, including internalization, dissociation of insulin from the internalized receptor within an acidified compartment, segregation of insulin from the receptor, and subsequent ligand degradation.

  17. Intracellular insulin-receptor dissociation and segregation in a rat fibroblast cell line transfected with a human insulin receptor gene

    International Nuclear Information System (INIS)

    The cellular processing of insulin and insulin receptors was studied using a rat fibroblast cell line that had been transfected with a normal human insulin receptor gene, expressing approximately 500 times the normal number of native fibroblasts insulin receptors. These cells bind and internalize insulin normally. Biochemically assays based on the selective precipitation by polyethylene glycol of intact insulin-receptor complexes but not of free intracellular insulin were developed to study the time course of intracellular insulin-receptor dissociation. Fibroblasts were incubated with radiolabeled insulin at 40C, and internalization of insulin-receptor complexes was initiated by warming the cells to 370C. Within 2 min, 90% of the internalized radioactivity was composed of intact insulin-receptor complexes. The dissociation of insulin from internalized insulin-receptor complexes was markedly inhibited by monensin and chloroquine. Furthermore, chloroquine markedly increased the number of cross-linkable intracellular insulin-receptor complexes, as analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis autoradiography. These findings suggest that acidification of intracellular vesicles is responsible for insulin-receptor dissociation. Physical segregation of dissociated intracellular insulin from its receptor was monitored. The results are consistent with the view that segregation of insulin and receptor occurs 5-10 min after initiation of dissociation. These studies demonstrate the intracellular itinerary of insulin-receptor complexes, including internalization, dissociation of insulin from the internalized receptor within an acidified compartment, segregation of insulin from the receptor, and subsequent ligand degradation

  18. Are the angiotensin-converting enzime gene and acticity risk factors for stroke? São fatores de risco para acidente vascular cerebral o gene e a atividade da enzima conversora de angiotensina ?

    Directory of Open Access Journals (Sweden)

    Miris Dikmen

    2006-06-01

    Full Text Available Stroke is a multifactorial disease in which genetic factors play an important role. This study was carried out to determine angiotensin-converting enzyme (ACE gene polymorphism in Turkish acute stroke patients and to establish whether there is an association of angiotensin-converting enzyme gene I/D polymorphism with clinical parameters. In this study 185 patients and 50 controls were recruited. We have investigated the association among the allelic distribution of the insertion/deletion (I/D polymorphism of the ACE gene identified by polymerase chain reaction. Distribution of ACE gene I/D genotypes and allele frequencies in patients were not significantly different from controls. D allele frequencies were 57.8% in patients versus 53.0% in controls and I allele 42.2% versus 47% respectively. History of hypertension, stroke, renal, heart and vessel diseases incidence and age, gender, systolic-diastolic blood pressures and creatinine levels were significantly high in patients. But these results and ACE activities had no significant differences among the ACE genotypes in patients and controls. Our results suggest that the ACE gene polymorphism is not associated with the pathogenesis of stroke in Turkish stroke patients.O acidente vascular cerebral (AVC é doença multifatorial em que fatores genéticos desempenham papel importante. Este estudo foi desenvolvido para verificar o polimorfismo do gene da enzima conversora da angiotensina (ECA em pacientes turcos com AVC agudo e estabelecer se existe associação do gene I/D da ECA com parâmetros clínicos. O estudo foi realizado com 185 pacientes e 50 controles. A associação entre a distribuição alélica da inserção / deleção (I/D do polimorfismo do gene da ECA foi estudada pela reação em cadeia da polimerase. A distribuição dos genótipos I/D do gene da ECA e suas freqüências não apresentaram significância estatística quando comparados os pacientes e controles. As freqüências dos

  19. The Renin-Angiotensin System Modulates Inflammatory Processes in Atherosclerosis: Evidence from Basic Research and Clinical Studies

    Directory of Open Access Journals (Sweden)

    Fabrizio Montecucco

    2009-01-01

    Full Text Available Recent evidence shows that the renin-angiotensin system is a crucial player in atherosclerotic processes. The regulation of arterial blood pressure was considered from its first description of the main mechanism involved. Vasoconstriction (mediated by angiotensin II and salt and water retention (mainly due to aldosterone were classically considered as pivotal proatherosclerotic activities. However, basic research and animal studies strongly support angiotensin II as a proinflammatory mediator, which directly induces atherosclerotic plaque development and heart remodeling. Furthermore, angiotensin II induces proatherosclerotic cytokine and chemokine secretion and increases endothelial dysfunction. Accordingly, the pharmacological inhibition of the renin-angiotensin system improves prognosis of patients with cardiovascular disease even in settings of normal baseline blood pressure. In the present review, we focused on angiotensin-convertingenzyme (ACE inhibitors, angiotensin II receptor blockers (ARBs, and renin inhibitors to update the direct activities of the renin-angiotensin system in inflammatory processes governing atherosclerosis.

  20. The adipose renin-angiotensin system modulates sysemic markers of insulin sensitivity activates the intrarenal renin-angiotensin system

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Suyeon [University of Tennessee, Knoxville (UTK); Soltani-Bejnood, Morvarid [University of Tennessee, Knoxville (UTK); Quignard-Boulange, Annie [Centre Biomedical des Cordeliers, Paris, France; Massiera, Florence [Centre de Biochimie, Nice, France; Teboul, Michele [Centre de Biochimie, Nice, France; Ailhaud, Gerard [Centre de Biochimie, Nice, France; Kim, Jung [University of Tennessee, Knoxville (UTK); Moustaid-Moussa, Naima [University of Tennessee, Knoxville (UTK); Voy, Brynn H [ORNL

    2006-07-01

    BACKGROUND: A growing body of data provides increasing evidence that the adipose tissue renin-angiotensin system (RAS) contributes to regulation of fat mass. Beyond its paracrine actions within adipose tissue, adipocyte-derived angiotensin II (Ang II) may also impact systemic functions such as blood pressure and metabolism. METHODS AND RESULTS: We used a genetic approach to manipulate adipose RAS activity in mice and then study the consequences on metabolic parameters and on feedback regulation of the RAS. The models included deletion of the angiotensinogen (Agt) gene (Agt-KO), its expression solely in adipose tissue under the control of an adipocyte-specific promoter (aP2-Agt/ Agt-KO), and overexpression in adipose tissue of wild type mice (aP2-Agt). Total body weight, epididymal fat pad weight, and circulating levels of leptin, insulin and resistin were significantly decreased in Agt-KO mice, while plasma adiponectin levels were increased. Overexpression of Agt in adipose tissue resulted in increased adiposity and plasma leptin and insulin levels compared to wild type (WT) controls. Angiotensinogen and type I Ang II receptor protein levels were also markedly elevated in kidney of aP2-Agt mice, suggesting that hypertension in these animals may be in part due to stimulation of the intrarenal RAS. CONCLUSIONS: Taken together, the results from this study demonstrate that alterations in adipose RAS activity significantly alter both local and systemic physiology in a way that may contribute to the detrimental health effects of obesity.

  1. Cardiac gene expression data and in silico analysis provide novel insights into human and mouse taste receptor gene regulation.

    Science.gov (United States)

    Foster, Simon R; Porrello, Enzo R; Stefani, Maurizio; Smith, Nicola J; Molenaar, Peter; dos Remedios, Cristobal G; Thomas, Walter G; Ramialison, Mirana

    2015-10-01

    G protein-coupled receptors are the principal mediators of the sweet, umami, bitter, and fat taste qualities in mammals. Intriguingly, the taste receptors are also expressed outside of the oral cavity, including in the gut, airways, brain, and heart, where they have additional functions and contribute to disease. However, there is little known about the mechanisms governing the transcriptional regulation of taste receptor genes. Following our recent delineation of taste receptors in the heart, we investigated the genomic loci encoding for taste receptors to gain insight into the regulatory mechanisms that drive their expression in the heart. Gene expression analyses of healthy and diseased human and mouse hearts showed coordinated expression for a subset of chromosomally clustered taste receptors. This chromosomal clustering mirrored the cardiac expression profile, suggesting that a common gene regulatory block may control the taste receptor locus. We identified unique domains with strong regulatory potential in the vicinity of taste receptor genes. We also performed de novo motif enrichment in the proximal promoter regions and found several overrepresented DNA motifs in cardiac taste receptor gene promoters corresponding to ubiquitous and cardiac-specific transcription factor binding sites. Thus, combining cardiac gene expression data with bioinformatic analyses, this study has provided insights into the noncoding regulatory landscape for taste GPCRs. These findings also have broader relevance for the study of taste GPCRs outside of the classical gustatory system, where understanding the mechanisms controlling the expression of these receptors may have implications for future therapeutic development. PMID:25986534

  2. The Orphan Nuclear Receptor ERRγ Regulates Hepatic CB1 Receptor-Mediated Fibroblast Growth Factor 21 Gene Expression

    Science.gov (United States)

    Jung, Yoon Seok; Lee, Ji-Min; Kim, Don-Kyu; Lee, Yong-Soo; Kim, Ki-Sun; Kim, Yong-Hoon; Kim, Jina; Lee, Myung-Shik; Lee, In-Kyu; Kim, Seong Heon; Cho, Sung Jin; Jeong, Won-Il; Lee, Chul-Ho; Harris, Robert A.; Choi, Hueng-Sik

    2016-01-01

    Background Fibroblast growth factor 21 (FGF21), a stress inducible hepatokine, is synthesized in the liver and plays important roles in glucose and lipid metabolism. However, the mechanism of hepatic cannabinoid type 1 (CB1) receptor-mediated induction of FGF21 gene expression is largely unknown. Results Activation of the hepatic CB1 receptor by arachidonyl-2’-chloroethylamide (ACEA), a CB1 receptor selective agonist, significantly increased FGF21 gene expression. Overexpression of estrogen-related receptor (ERR) γ increased FGF21 gene expression and secretion both in hepatocytes and mice, whereas knockdown of ERRγ decreased ACEA-mediated FGF21 gene expression and secretion. Moreover, ERRγ, but not ERRα and ERRβ, induced FGF21 gene promoter activity. In addition, deletion and mutation analysis of the FGF21 promoter identified a putative ERRγ-binding motif (AGGTGC, a near-consensus response element). A chromatin immunoprecipitation assay revealed direct binding of ERRγ to the FGF21 gene promoter. Finally, GSK5182, an ERRγ inverse agonist, significantly inhibited hepatic CB1 receptor-mediated FGF21 gene expression and secretion. Conclusion Based on our data, we conclude that ERRγ plays a key role in hepatic CB1 receptor-mediated induction of FGF21 gene expression and secretion. PMID:27455076

  3. Evolution of the Sweet Taste Receptor Gene Tas1r2 in Bats

    OpenAIRE

    Zhao, Huabin; Zhou, Yingying; Pinto, C. Miguel; Charles-Dominique, Pierre; Galindo-González, Jorge; Zhang, Shuyi; Zhang, Jianzhi

    2010-01-01

    Taste perception is an important component of an animal's fitness. The identification of vertebrate taste receptor genes in the last decade has enabled molecular genetic studies of the evolution of taste perception in the context of the ecology and dietary preferences of organisms. Although such analyses have been conducted in a number of species for bitter taste receptors, a similar analysis of sweet taste receptors is lacking. Here, we survey the sole sweet taste–specific receptor gene Tas1...

  4. Evolution of dopamine receptor genes of the D1 class in vertebrates.

    Science.gov (United States)

    Yamamoto, Kei; Mirabeau, Olivier; Bureau, Charlotte; Blin, Maryline; Michon-Coudouel, Sophie; Demarque, Michaël; Vernier, Philippe

    2013-04-01

    The receptors of the dopamine neurotransmitter belong to two unrelated classes named D1 and D2. For the D1 receptor class, only two subtypes are found in mammals, the D1A and D1B, receptors, whereas additional subtypes, named D1C, D1D, and D1X, have been found in other vertebrate species. Here, we analyzed molecular phylogeny, gene synteny, and gene expression pattern of the D1 receptor subtypes in a large range of vertebrate species, which leads us to propose a new view of the evolution of D1 dopamine receptor genes. First, we show that D1C and D1D receptor sequences are encoded by orthologous genes. Second, the previously identified Cypriniform D1X sequence is a teleost-specific paralog of the D1B sequences found in all groups of jawed vertebrates. Third, zebrafish and several sauropsid species possess an additional D1-like gene, which is likely to form another orthology group of vertebrate ancestral genes, which we propose to name D1E. Ancestral jawed vertebrates are thus likely to have possessed four classes of D1 receptor genes-D1A, D1B(X), D1C(D), and D1E-which arose from large-scale gene duplications. The D1C receptor gene would have been secondarily lost in the mammalian lineage, whereas the D1E receptor gene would have been lost independently in several lineages of modern vertebrates. The D1A receptors are well conserved throughout jawed vertebrates, whereas sauropsid D1C receptors have rapidly diverged, to the point that they were misidentified as D1D. The functional significance of the D1C receptor loss is not known. It is possible that the function may have been substituted with D1A or D1B receptors in mammals, following the disappearance of D1C receptors in these species. PMID:23197594

  5. Interleukin-4 receptor alpha gene variants and allergic disease

    Directory of Open Access Journals (Sweden)

    Hall Ian P

    2000-06-01

    Full Text Available Abstract The interleukin-4 (IL-4 signalling cascade has been identified as a pathway potentially important in the development of asthma. Genetic variants within this signalling pathway might contribute to the risk of developing asthma in a given individual. A number of polymorphisms have been described within the IL-4 receptor α (IL-4Rα gene. In addition polymorphism occurs in the promoter for the IL-4 gene itself. This commentary accompanies a paper by C Ober et al describing the contribution of IL-4Rα polymorphism to susceptibility to asthma and atopy in the Hutterite population and other outbred populations collected during the collaborative studies on the genetics of asthma (CSGA programme.

  6. Interleukin 18 receptor 1 gene polymorphisms are associated with asthma

    DEFF Research Database (Denmark)

    Zhu, Guohua; Whyte, Moira K B; Vestbo, Jørgen;

    2008-01-01

    The interleukin 18 receptor (IL18R1) gene is a strong candidate gene for asthma. It has been implicated in the pathophysiology of asthma and maps to an asthma susceptibility locus on chromosome 2q12. The possibility of association between polymorphisms in IL18R1 and asthma was examined by...... genotyping seven SNPs in 294, 342 and 100 families from Denmark, United Kingdom and Norway and conducting family-based association analyses for asthma, atopic asthma and bronchial hyper-reactivity (BHR) phenotypes. Three SNPs in IL18R1 were associated with asthma (0.01131 < or = P < or = 0.01377), five with...... polymorphisms in IL18R1 and asthma....

  7. Angiotensin II Differentially Induces Matrix Metalloproteinase-9 and Tissue Inhibitor of Metalloproteinase-1 Production and Disturbs MMP/TIMP Balance

    OpenAIRE

    Yaghooti, Hamid; Firoozrai, Mohsen; Fallah, Soudabeh; Khorramizadeh, Mohammad Reza

    2010-01-01

    Angiotensin II, the main component of the renin-angiotensin system, is associated with cardiovascular diseases such as hypertension, vascular remodeling and inflammation. Remodeling process results from dysregulation of Matrix Metalloproteinases (MMPs) and their tissue inhibitors (TIMPs). MMPs are considered as important target genes for angiotensin II. The aim of this study was to determine the effects of angiotensin II on MMP-9 and TIMP-1 production and MMP/TIMP balance in a monocytic cell ...

  8. Observations on the evolution of the melanocortin receptor gene family: distinctive features of the melanocortin-2 receptor

    Directory of Open Access Journals (Sweden)

    Robert Michael Dores

    2013-04-01

    Full Text Available The melanocortin receptors are a gene family in the rhodopsin class of G protein-coupled receptors. Based on the analysis of several metazoan genome databases it appears that the melanocortin receptors are only found in chordates. The presence of five genes in the family (i.e., MC1R, MC2R, MC3R, MC4R, MC5R in representatives of the tetrapods indicates that the gene family is the result of two genome duplication events and one local gene duplication event during the evolution of the chordates. The melanocortin receptors are activated by melanocortin ligands (i.e., ACTH, α-MSH, β-MSH, γ-MSH, δ-MSH which are all derived from the polypeptide hormone/neuropeptide precursor, POMC, and as a result the functional evolution of the melanocortin receptors is intimately associated with the co-evolution of POMC endocrine and neuronal circuits. This review will consider the origin of the melanocortin receptors, and discuss the evolutionary relationship between MC2R, MC5R, and MC4R. In addition, this review will analyze the functional evolution of the mc2r gene in light of the co-evolution of the MRAP (Melanocortin-2 Receptor Accessory Protein gene family.

  9. Multilocus analyses of renin-angiotensin-aldosterone system gene variants on blood pressure at rest and during behavioral stress in young normotensive subjects

    NARCIS (Netherlands)

    Ge, Dongliang; Zhu, Haidong; Huang, Ying; Treiber, Frank A.; Harshfield, Gregory A.; Snieder, Harold; Dong, Yanbin

    2007-01-01

    The renin-angiotensin-aldosterone system (RAAS) is a proteolytic cascade that regulates and maintains blood pressure (BP). This study aimed to explore the interactive and integrative effects of multiple RAAS polymorphisms on BP at rest and during behavioral stress in a normotensive population. A tot

  10. Identical splicing of aberrant epidermal growth factor receptor transcripts from amplified rearranged genes in human glioblastomas.

    OpenAIRE

    Sugawa, N; Ekstrand, A J; James, C D; Collins, V P

    1990-01-01

    The epidermal growth factor receptor gene has been found to be amplified and rearranged in human glioblastomas in vivo. Here we present the sequence across a splice junction of aberrant epidermal growth factor receptor transcripts derived from corresponding and uniquely rearranged genes that are coamplified and coexpressed with non-rearranged epidermal growth factor receptor genes in six primary human glioblastomas. Each of these six tumors contains aberrant transcripts derived from identical...

  11. Reduced Expression of the Extracellular Calcium-Sensing Receptor (CaSR) Is Associated with Activation of the Renin-Angiotensin System (RAS) to Promote Vascular Remodeling in the Pathogenesis of Essential Hypertension

    Science.gov (United States)

    Wang, La-mei; Tang, Na; Zhong, Hua; Liu, Yong-min; Li, Zhen; Feng, Qian; He, Fang

    2016-01-01

    The proliferation of vascular smooth muscle cells (VSMCs), remodeling of the vasculature, and the renin-angiotensin system (RAS) play important roles in the development of essential hypertension (EH), which is defined as high blood pressure (BP) in which secondary causes, such as renovascular disease, are absent. The calcium-sensing receptor (CaSR) is involved in the regulation of BP. However, the underlying mechanisms by which the CaSR regulates BP are poorly understood. In the present study, the role of the CaSR in EH was investigated using male spontaneously hypertensive rats (SHRs) and rat and human plasma samples. The percentages of medial wall thickness to external diameter (WT%), total vessel wall cross-sectional area to the total area (WA%) of thoracic arteries, as well as the percentage of wall area occupied by collagen to total vessel wall area (CA%) were determined. Tissue protein expression and plasma concentrations of the CaSR, cyclic adenosine monophosphate (cAMP), renin, and angiotensin II (Ang II) were additionally assessed. WT%, WA%, and CA% were found to increase with increasing BP, whereas the plasma concentration of CaSR was found to decrease. With increasing BP, the levels of smooth muscle actin and calponin decreased, whereas those of osteopontin and proliferating cell nuclear antigen increased. The CaSR level negatively correlated with the levels of cAMP and Ang II, but positively correlated with those of renin. Our data suggest that reduced expression of the CaSR is correlated with activation of the RAS, which induces increased vascular remodeling and VSMC proliferation, and thereby associated with EH in the SHR model and in the Han Chinese population. Our findings provide new insights into the pathogenesis of EH. PMID:27391973

  12. Transcriptional up-regulation of antioxidant genes by PPARδ inhibits angiotensin II-induced premature senescence in vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Research highlights: → Activation of PPARδ by GW501516 significantly inhibited Ang II-induced premature senescence in hVSMCs. → Agonist-activated PPARδ suppressed generation of Ang II-triggered ROS with a concomitant reduction in DNA damage. → GW501516 up-regulated expression of antioxidant genes, such as GPx1, Trx1, Mn-SOD and HO-1. → Knock-down of these antioxidant genes abolished the effects of GW501516 on ROS production and premature senescence. -- Abstract: This study evaluated peroxisome proliferator-activated receptor (PPAR) δ as a potential target for therapeutic intervention in Ang II-induced senescence in human vascular smooth muscle cells (hVSMCs). Activation of PPARδ by GW501516, a specific agonist of PPARδ, significantly inhibited the Ang II-induced premature senescence of hVSMCs. Agonist-activated PPARδ suppressed the generation of Ang II-triggered reactive oxygen species (ROS) with a concomitant reduction in DNA damage. Notably, GW501516 up-regulated the expression of antioxidant genes, such as glutathione peroxidase 1, thioredoxin 1, manganese superoxide dismutase and heme oxygenase 1. siRNA-mediated down-regulation of these antioxidant genes almost completely abolished the effects of GW501516 on ROS production and premature senescence in hVSMCs treated with Ang II. Taken together, the enhanced transcription of antioxidant genes is responsible for the PPARδ-mediated inhibition of premature senescence through sequestration of ROS in hVSMCs treated with Ang II.

  13. Clone and expression of human transferrin receptor gene: a marker gene for magnetic resonance imaging

    International Nuclear Information System (INIS)

    Objective: To clone human transferrin receptor (hTfR) gene and construct expression vector producing recombination protein. Methods: Human transferrin receptor gene cDNA was amplified by RT-PCR from human embryonic liver and lung tissue. Recombinant pcDNA3-hTfR and pEGFP-Cl-hTfR plasmids were constructed and confirmed by DNA sequencing. These plasmids were stably transfected into the HEK293 cells. The protein expression in vitro was confirmed by Western Blot. The efficiency of expression and the location of hTfR were also investigated by fluorescence microscopy and confocal fluorescence microscopy. Results: The full length cDNA of hTfR gene (2332 bp) was cloned and sequenced. The hTfR (190 000) was overexpressed in transfected HEK293 cells by Western blot analysis. Fluorescence micrographs displayed that the hTfR was expressed at high level and located predominantly in the cell surface. Conclusions: Human transferrin receptor (hTfR) gene has been successfully cloned and obtained high-level expression in HEK293 cells, and the recombination protein of hTfR distributed predominantly in the cell membrane. (authors)

  14. Transient receptor potential (TRP gene superfamily encoding cation channels

    Directory of Open Access Journals (Sweden)

    Pan Zan

    2011-01-01

    Full Text Available Abstract Transient receptor potential (TRP non-selective cation channels constitute a superfamily, which contains 28 different genes. In mammals, this superfamily is divided into six subfamilies based on differences in amino acid sequence homology between the different gene products. Proteins within a subfamily aggregate to form heteromeric or homomeric tetrameric configurations. These different groupings have very variable permeability ratios for calcium versus sodium ions. TRP expression is widely distributed in neuronal tissues, as well as a host of other tissues, including epithelial and endothelial cells. They are activated by environmental stresses that include tissue injury, changes in temperature, pH and osmolarity, as well as volatile chemicals, cytokines and plant compounds. Their activation induces, via intracellular calcium signalling, a host of responses, including stimulation of cell proliferation, migration, regulatory volume behaviour and the release of a host of cytokines. Their activation is greatly potentiated by phospholipase C (PLC activation mediated by coupled GTP-binding proteins and tyrosine receptors. In addition to their importance in maintaining tissue homeostasis, some of these responses may involve various underlying diseases. Given the wealth of literature describing the multiple roles of TRP in physiology in a very wide range of different mammalian tissues, this review limits itself to the literature describing the multiple roles of TRP channels in different ocular tissues. Accordingly, their importance to the corneal, trabecular meshwork, lens, ciliary muscle, retinal, microglial and retinal pigment epithelial physiology and pathology is reviewed.

  15. Oxytocin receptor and vasopressin receptor 1a genes are respectively associated with emotional and cognitive empathy.

    Science.gov (United States)

    Uzefovsky, F; Shalev, I; Israel, S; Edelman, S; Raz, Y; Mankuta, D; Knafo-Noam, A; Ebstein, R P

    2015-01-01

    Empathy is the ability to recognize and share in the emotions of others. It can be considered a multifaceted concept with cognitive and emotional aspects. Little is known regarding the underlying neurochemistry of empathy and in the current study we used a neurogenetic approach to explore possible brain neurotransmitter pathways contributing to cognitive and emotional empathy. Both the oxytocin receptor (OXTR) and the arginine vasopressin receptor 1a (AVPR1a) genes contribute to social cognition in both animals and humans and hence are prominent candidates for contributing to empathy. The following research examined the associations between polymorphisms in these two genes and individual differences in emotional and cognitive empathy in a sample of 367 young adults. Intriguingly, we found that emotional empathy was associated solely with OXTR, whereas cognitive empathy was associated solely with AVPR1a. Moreover, no interaction was observed between the two genes and measures of empathy. The current findings contribute to our understanding of the distinct neurogenetic pathways involved in cognitive and emotional empathy and underscore the pervasive role of both oxytocin and vasopressin in modulating human emotions. PMID:25476609

  16. Influence of aerobic training on the reduced vasoconstriction to angiotensin II in rats exposed to intrauterine growth restriction: possible role of oxidative stress and AT2 receptor of angiotensin II.

    Directory of Open Access Journals (Sweden)

    Vanessa Oliveira

    Full Text Available Intrauterine growth restriction (IUGR is associated with impaired vascular function, which contributes to the increased incidence of chronic disease. The aim of this study was to investigate whether aerobic training improves AngII-induced vasoconstriction in IUGR rats. Moreover, we assess the role of superoxide dismutase (SOD isoforms and NADPH oxidase-derived superoxide anions in this improvement. Female Wistar rats were randomly divided into two groups on day 1 of pregnancy. A control group was fed standard chow ad libitum, and a restricted group was fed 50% of the ad libitum intake throughout gestation. At 8 weeks of age, male offspring from both groups were randomly assigned to 4 experimental groups: sedentary control (SC, trained control (TC, sedentary restricted (SRT, and trained restricted (TRT. The training protocol was performed on a treadmill and consisted of a continuous 60-min session 5 days/week for 10 weeks. Following aerobic training, concentration-response curves to AngII were obtained in endothelium-intact aortic rings. Protein expression of SOD isoforms, AngII receptors and the NADPH oxidase component p47phox was assessed by Western blot analysis. The dihydroethidium was used to evaluate the in situ superoxide levels under basal conditions or in the presence of apocynin, losartan or PD 123,319. Our results indicate that aerobic training can prevent IUGR-associated increases in AngII-dependent vasoconstriction and can restore basal superoxide levels in the aortic rings of TRT rats. Moreover, we observed that aerobic training normalized the increased p47phox protein expression and increased MnSOD and AT2 receptor protein expression in thoracic aortas of SRT rats. In summary, aerobic training can result in an upregulation of antioxidant defense by improved of MnSOD expression and attenuation of NADPH oxidase component p47phox. These effects are accompanied by increased expression of AT2 receptor, which provide positive effects

  17. Angiopoietin-1 attenuates angiotensin II-induced ER stress in glomerular endothelial cells via a Tie2 receptor/ERK1/2-p38 MAPK-dependent mechanism.

    Science.gov (United States)

    Bi, Xiao; Niu, Jianying; Ding, Wei; Zhang, Minmin; Yang, Min; Gu, Yong

    2016-06-15

    Research has indicated that endoplasmic reticulum (ER) stress in endothelial cells affects vascular pathologies and induces cellular dysfunction and apoptosis. Angiopoietin1 (Angpt1) has been shown to have therapeutic potential in some vascular diseases, including chronic kidney disease. This study showed that Angpt1 is a powerful factor that attenuated ER stress-induced cellular dysfunction and apoptosis in glomerular endothelial cells (GEnCs). Furthermore, Angpt1 significantly decreased the angiotensin II (Ang II)-induced expression of the ER stress response proteins GRP78, GRP94, p-PERK and CHOP. These results suggest that the Angpt1-mediated cellular protection may occur downstream of the ER stress response. In addition, both specific inhibitors and siRNAs for Tie2 reversed these changes, implying the importance of Tie2 receptor activation in the signalling pathways that prevent ER stress. The protective effects of Angpt1 are related to the activation of two downstream signalling pathways, ERK1/2 and p38 MAPK. The inhibition of these pathways with specific inhibitors, PD98059 and SB203580, respectively, partially increased the expression of chaperones that assist in folding proteins in the ER and reduce the protective effects of Angpt1. In conclusion, Angpt1 attenuated ER stress-induced cellular dysfunction and apoptosis via the Tie2 receptor/ERK1/2-p38 MAPK pathways in GEnCs. This study may provide insights into a novel underlying mechanism and a strategy for alleviating ER stress-induced injury. PMID:27033326

  18. Effect of Angiotensin II on Blood Flow in Acute and Chronically Inflamed Knee Joints of Rabbits: The Role of Nitric Oxide

    Directory of Open Access Journals (Sweden)

    Hamid Najafipour

    2009-03-01

    Full Text Available Background: Angiotensin converting enzyme (ACE upregulationin stromal cells of joints affected by rheumatoid arthritismay lead to higher tissue angiotensin II that is a vasoconstrictorand mitogen factor. To date, the role of angiotensin II onregulating blood flow in inflamed joints has not been studied.Methods: Acute and chronic joint inflammation was inducedin rabbits by intra-articular injection of carrageenan and antigen-induced arthritis method, respectively. The ACE level ofsynovial fluid and the response of joint blood flow to angiotensinII, angiotensin II receptor antagonist, and the role ofnitric oxide (NO in modulation of the effects of angiotensin IIon joint blood vessels were examined.Results: The synovial fluid level of ACE was significantly increasedduring the process of inflammation and angiotensin IIincreased joint vascular resistance dose-dependently in both acuteand chronically inflamed joints. The angiotensin 1 receptor antagonistlosartan completely blocked the vasoconstrictor effect ofangiotensin II on joint blood vessels and induced vasodilatation.Nitric oxide synthase inhibitor N-omega -nitro L- argininemethyl ester (L-NAME increased joint vascular resistance andaugmented vascular response of inflamed joints to angiotensin II.Conclusion: Angiotensin II receptors in joint blood vesselsare angiotensin -1 subtype, and inflammation significantlyincreases the activity of synovial fluid ACE. Nitric oxide playsa significant role on regulating joint blood flow and in modulationof angiotensin 1 receptor-mediated vasoconstriction ofinflamed joint blood vessels.

  19. Mitogen-activated protein kinase kinase 1/2 inhibition and angiotensin II converting inhibition in mice with cardiomyopathy caused by lamin A/C gene mutation

    International Nuclear Information System (INIS)

    Highlights: • Both ACE and MEK1/2 inhibition are beneficial on cardiac function in Lmna cardiomyopathy. • MEK1/2 inhibitor has beneficial effects beyond ACE inhibition for Lmna cardiomyopathy. • These results provide further preclinical rationale for a clinical trial of a MEK1/2 inhibitor. - Abstract: Background: Mutations in the LMNA gene encoding A-type nuclear lamins can cause dilated cardiomyopathy with or without skeletal muscular dystrophy. Previous studies have shown abnormally increased extracellular signal-regulated kinase 1/2 activity in hearts of LmnaH222P/H222P mice, a small animal model. Inhibition of this abnormal signaling activity with a mitogen-activated protein kinase kinase 1/2 (MEK1/2) inhibitor has beneficial effects on heart function and survival in these mice. However, such treatment has not been examined relative to any standard of care intervention for dilated cardiomyopathy or heart failure. We therefore examined the effects of an angiotensin II converting enzyme (ACE) inhibitor on left ventricular function in LmnaH222P/H222P mice and assessed if adding a MEK1/2 inhibitor would provide added benefit. Methods: Male LmnaH222P/H222P mice were treated with the ACE inhibitor benazepril, the MEK1/2 inhibitor selumetinib or both. Transthoracic echocardiography was used to measure left ventricular diameters and fractional shortening was calculated. Results: Treatment of LmnaH222P/H222P mice with either benazepril or selumetinib started at 8 weeks of age, before the onset of detectable left ventricular dysfunction, lead to statistically significantly increased fractional shortening compared to placebo at 16 weeks of age. There was a trend towards a great value for fractional shortening in the selumetinib-treated mice. When treatment was started at 16 weeks of age, after the onset of left ventricular dysfunction, the addition of selumetinib treatment to benazepril lead to a statistically significant increase in left ventricular fractional

  20. Mitogen-activated protein kinase kinase 1/2 inhibition and angiotensin II converting inhibition in mice with cardiomyopathy caused by lamin A/C gene mutation

    Energy Technology Data Exchange (ETDEWEB)

    Muchir, Antoine, E-mail: a.muchir@institut-myologie.org [Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY (United States); Department of Pathology and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, NY (United States); Wu, Wei [Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY (United States); Department of Pathology and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, NY (United States); Sera, Fusako; Homma, Shunichi [Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY (United States); Worman, Howard J., E-mail: hjw14@columbia.edu [Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY (United States); Department of Pathology and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, NY (United States)

    2014-10-03

    Highlights: • Both ACE and MEK1/2 inhibition are beneficial on cardiac function in Lmna cardiomyopathy. • MEK1/2 inhibitor has beneficial effects beyond ACE inhibition for Lmna cardiomyopathy. • These results provide further preclinical rationale for a clinical trial of a MEK1/2 inhibitor. - Abstract: Background: Mutations in the LMNA gene encoding A-type nuclear lamins can cause dilated cardiomyopathy with or without skeletal muscular dystrophy. Previous studies have shown abnormally increased extracellular signal-regulated kinase 1/2 activity in hearts of Lmna{sup H222P/H222P} mice, a small animal model. Inhibition of this abnormal signaling activity with a mitogen-activated protein kinase kinase 1/2 (MEK1/2) inhibitor has beneficial effects on heart function and survival in these mice. However, such treatment has not been examined relative to any standard of care intervention for dilated cardiomyopathy or heart failure. We therefore examined the effects of an angiotensin II converting enzyme (ACE) inhibitor on left ventricular function in Lmna{sup H222P/H222P} mice and assessed if adding a MEK1/2 inhibitor would provide added benefit. Methods: Male Lmna{sup H222P/H222P} mice were treated with the ACE inhibitor benazepril, the MEK1/2 inhibitor selumetinib or both. Transthoracic echocardiography was used to measure left ventricular diameters and fractional shortening was calculated. Results: Treatment of Lmna{sup H222P/H222P} mice with either benazepril or selumetinib started at 8 weeks of age, before the onset of detectable left ventricular dysfunction, lead to statistically significantly increased fractional shortening compared to placebo at 16 weeks of age. There was a trend towards a great value for fractional shortening in the selumetinib-treated mice. When treatment was started at 16 weeks of age, after the onset of left ventricular dysfunction, the addition of selumetinib treatment to benazepril lead to a statistically significant increase in left

  1. Cardiovascular actions of angiotensin-(1-7

    Directory of Open Access Journals (Sweden)

    Ferreira A.J.

    2005-01-01

    Full Text Available Angiotensin-(1-7 (Ang-(1-7 is now considered to be a biologically active member of the renin-angiotensin system. The functions of Ang-(1-7 are often opposite to those attributed to the main effector component of the renin-angiotensin system, Ang II. Chronic administration of angiotensin-converting enzyme inhibitors (ACEI increases 10- to 25-fold the plasma levels of this peptide, suggesting that part of the beneficial effects of ACEI could be mediated by Ang-(1-7. Ang-(1-7 can be formed from Ang II or directly from Ang I. Other enzymatic pathways for Ang-(1-7 generation have been recently described involving the novel ACE homologue ACE2. This enzyme can form Ang-(1-7 from Ang II or less efficiently by the hydrolysis of Ang I to Ang-(1-9 with subsequent Ang-(1-7 formation. The biological relevance of Ang-(1-7 has been recently reinforced by the identification of its receptor, the G-protein-coupled receptor Mas. Heart and blood vessels are important targets for the formation and actions of Ang-(1-7. In this review we will discuss recent findings concerning the biological role of Ang-(1-7 in the heart and blood vessels, taking into account aspects related to its formation and effects on these tissues. In addition, we will discuss the potential of Ang-(1-7 and its receptor as a target for the development of new cardiovascular drugs.

  2. Angiotensin-converting enzymes modulate aphid–plant interactions

    OpenAIRE

    Wei Wang; Lan Luo; Hong Lu; Shaoliang Chen; Le Kang; Feng Cui

    2015-01-01

    Angiotensin-converting enzymes (ACEs) are key components of the renin–angiotensin system in mammals. However, the function of ACE homologs in insect saliva is unclear. Aphids presumably deliver effector proteins via saliva into plant cells to maintain a compatible insect–plant interaction. In this study, we showed that ACE modulates aphid–plant interactions by affecting feeding behavior and survival of aphids on host plants. Three ACE genes were identified from the pea aphid Acyrthosiphon pis...

  3. Angiotensin-converting enzyme

    DEFF Research Database (Denmark)

    Sørensen, P G; Rømer, F K; Cortes, D

    1984-01-01

    In order to evaluate bleomycin-associated lung damage in humans, lung function parameters and serum levels of the endothelial-bound angiotensin-converting enzyme (ACE) were determined by serial measurements in 11 patients who were treated for testicular cancer. None developed clinical or radiolog......In order to evaluate bleomycin-associated lung damage in humans, lung function parameters and serum levels of the endothelial-bound angiotensin-converting enzyme (ACE) were determined by serial measurements in 11 patients who were treated for testicular cancer. None developed clinical or...

  4. Angiotensin II activates different calcium signaling pathways in adipocytes.

    Science.gov (United States)

    Dolgacheva, Lyudmila P; Turovskaya, Maria V; Dynnik, Vladimir V; Zinchenko, Valery P; Goncharov, Nikolay V; Davletov, Bazbek; Turovsky, Egor A

    2016-03-01

    Angiotensin II (Ang II) is an important mammalian neurohormone involved in reninangiotensin system. Ang II is produced both constitutively and locally by RAS systems, including white fat adipocytes. The influence of Ang II on adipocytes is complex, affecting different systems of signal transduction from early Са(2+) responses to cell proliferation and differentiation, triglyceride accumulation, expression of adipokine-encoding genes and adipokine secretion. It is known that white fat adipocytes express all RAS components and Ang II receptors (АТ1 and АТ2). The current work was carried out with the primary white adipocytes culture, and Са(2+) signaling pathways activated by Ang II were investigated using fluorescent microscopy. Са(2+)-oscillations and transient responses of differentiated adipocytes to Ang II were registered in cells with both small and multiple lipid inclusions. Using inhibitory analysis and selective antagonists, we now show that Ang II initiates periodic Са(2+)-oscillations and transient responses by activating АТ1 and АТ2 receptors and involving branched signaling cascades:In these cascades, AT1 receptors play the leading role. The results of the present work open a perspective of using Ang II for correction of signal resistance of adipocytes often observed during obesity and type 2diabetes. PMID:26850364

  5. The Dopamine D2 Receptor Gene, Perceived Parental Support, and Adolescent Loneliness: Longitudinal Evidence for Gene-Environment Interactions

    Science.gov (United States)

    van Roekel, Eeske; Goossens, Luc; Scholte, Ron H. J.; Engels, Rutger C. M. E.; Verhagen, Maaike

    2011-01-01

    Background: Loneliness is a common problem in adolescence. Earlier research focused on genes within the serotonin and oxytocin systems, but no studies have examined the role of dopamine-related genes in loneliness. In the present study, we focused on the dopamine D2 receptor gene (DRD2). Methods: Associations among the DRD2, sex, parental support,…

  6. Variants in the vitamin D receptor gene and asthma

    Directory of Open Access Journals (Sweden)

    Wjst Matthias

    2005-01-01

    Full Text Available Abstract Background Early lifetime exposure to dietary or supplementary vitamin D has been predicted to be a risk factor for later allergy. Twin studies suggest that response to vitamin D exposure might be influenced by genetic factors. As these effects are primarily mediated through the vitamin D receptor (VDR, single base variants in this gene may be risk factors for asthma or allergy. Results 951 individuals from 224 pedigrees with at least 2 asthmatic children were analyzed for 13 SNPs in the VDR. There was no preferential transmission to children with asthma. In their unaffected sibs, however, one allele in the 5' region was 0.5-fold undertransmitted (p = 0.049, while two other alleles in the 3' terminal region were 2-fold over-transmitted (p = 0.013 and 0.018. An association was also seen with bronchial hyperreactivity against methacholine and with specific immunoglobulin E serum levels. Conclusion The transmission disequilibrium in unaffected sibs of otherwise multiple-affected families seem to be a powerful statistical test. A preferential transmission of vitamin D receptor variants to children with asthma could not be confirmed but raises the possibility of a protective effect for unaffected children.

  7. Identifying polymorphisms in the Rattus norvegicus D3 dopamine receptor gene and regulatory region

    NARCIS (Netherlands)

    Smits, B.M.; D'Souza, U.M.; Berezikov, E.; Cuppen, E.; Sluyter, F.

    2004-01-01

    The D(3) dopamine receptor has been implicated in several neuropsychiatric disorders, including schizophrenia, Parkinson's disease and addiction. Sequence variation in the D(3) gene can lead to subtle alteration in receptor structure or gene expression and thus to a different phenotype. In this stud

  8. An Expression Refinement Process Ensures Singular Odorant Receptor Gene Choice.

    Science.gov (United States)

    Abdus-Saboor, Ishmail; Al Nufal, Mohammed J; Agha, Maha V; Ruinart de Brimont, Marion; Fleischmann, Alexander; Shykind, Benjamin M

    2016-04-25

    Odorant receptor (OR) gene choice in mammals is a paradigmatic example of monogenic and monoallelic transcriptional selection, in which each olfactory sensory neuron (OSN) chooses to express one OR allele from over 1,000 encoded in the genome [1-3]. This process, critical for generation of the circuit from nose to brain [4-6], is thought to occur in two steps: a slow initial phase that randomly activates a single OR allele, followed by a rapid feedback that halts subsequent expression [7-14]. Inherent in this model is a finite failure rate wherein multiple OR alleles may be activated prior to feedback suppression [15, 16]. Confronted with more than one receptor, the neuron would need to activate a refinement mechanism to eliminate multigenic OR expression and resolve unique neuronal identity [16], critical to the generation of the circuit from nose to olfactory bulb. Here we used a genetic approach in mice to reveal a new facet of OR regulation that corrects adventitious activation of multiple OR alleles, restoring monogenic OR expression and unique neuronal identity. Using the tetM71tg model system, in which the M71 OR is expressed in >95% of mature OSNs and potently suppresses the expression of the endogenous OR repertoire [10], we provide clear evidence of a post-selection refinement (PSR) process that winnows down the number of ORs. We further demonstrate that PSR efficiency is linked to OR expression level, suggesting an underlying competitive process and shedding light on OR gene switching and the fundamental mechanism of singular OR choice. PMID:27040780

  9. Association between the polymorphisms of angiotensin converting enzyme (Peptidyl-Dipeptidase A INDEL mutation (I/D and Angiotensin II type I receptor (A1166C and breast cancer among post menopausal Egyptian females

    Directory of Open Access Journals (Sweden)

    Rania Mohamed El Sharkawy

    2014-09-01

    Results: A statistically significant difference in AT1R A1166C SNP genotype frequencies was found among the studied groups. The patients group showed higher frequency of “CC” (2.9% vs 0% and “AC” (44.3% vs 24% and lower frequency of “AA” genotype (52.9% vs 76% than controls. The patients also showed significant higher frequency of allele “C” (25% vs 12% which was associated with increased breast cancer risk with an Odds ratio of 2.4444 (95% CI: 1.1967–4.9931. Testing the dominant model of inheritance revealed a statistically higher frequency of exposed genotypes “AC and CC” among the patients group (47.1% vs 24%, respectively; p = 0.013 with substantial increase in breast cancer risk among the exposed genotypes with an Odds ratio of 2.8243 (95% CI: 1.2679–6.2913. The present study demonstrated that (AC and CC genotypes of AT1R A1166C SNP and increased BMI can be considered as predictors for breast cancer risk among post menopausal Egyptian females. Results also revealed that A1166C SNP of AT1R gene and ACE/ID polymorphism could not be considered as predictors for breast cancer prognosis.

  10. Thyroid hormone receptors bind to defined regions of the growth hormone and placental lactogen genes.

    OpenAIRE

    Barlow, J W; Voz, M L; Eliard, P H; Mathy-Harter, M; De Nayer, Philippe; Economidis, I V; Belayew, A; Martial, J A; Rousseau, Guy

    1986-01-01

    The intracellular receptor for thyroid hormone is a protein found in chromatin. Since thyroid hormone stimulates transcription of the growth hormone gene through an unknown mechanism, the hypothesis that the thyroid hormone-receptor complex interacts with defined regions of this gene has been investigated in a cell-free system. Nuclear extracts from human lymphoblastoid IM-9 cells containing thyroid hormone receptors were incubated with L-3,5,3'-tri[125I]iodothyronine and calf thymus DNA-cell...

  11. Toll-like receptor gene polymorphisms are associated with allergic rhinitis: a case control study

    OpenAIRE

    Nilsson Daniel; Andiappan Anand; Halldén Christer; Yun Wang; Säll Torbjörn; Tim Chew; Cardell Lars-Olaf

    2012-01-01

    Abstract Background The Toll-like receptor proteins are important in host defense and initiation of the innate and adaptive immune responses. A number of studies have identified associations between genetic variation in the Toll-like receptor genes and allergic disorders such as asthma and allergic rhinitis. The present study aim to search for genetic variation associated with allergic rhinitis in the Toll-like receptor genes. Methods A first association analysis genotyped 73 SNPs in 182 case...

  12. The Effect of Genetic Variation of the Retinoic Acid Receptor-Related Orphan Receptor C Gene on Fatness in Cattle

    OpenAIRE

    Barendse, W.; Bunch, R. J.; Kijas, J. W.; M. B. Thomas

    2007-01-01

    Genotypes at the retinoic acid receptor-related orphan receptor C (RORC) gene were associated with fatness in 1750 cattle. Ten SNPs were genotyped in RORC and the adjacent gene leucine-rich repeat neuronal 6D (LRRN6D) to map the QTL, 7 of which are in a 4.2-kb sequence around the ligand-binding domain of the RORC gene. Of the 29 inferred haplotypes for these SNPs, 2 have a combined frequency of 54.6% while the top 5 haplotypes have a combined frequency of 85.3%. The average D′ value of linkag...

  13. Effect of high glucose, angiotensin Ⅱ and receptor antagonist Losartan on the expression of connective tissue growth factor in cultured mesangial cells

    Institute of Scientific and Technical Information of China (English)

    黄颂敏; 刘芳; 沙朝晖; 付平; 杨一帆; 徐勇; 周海燕

    2003-01-01

    Objective To observe the effect of high glucose, angiotensin Ⅱ (AngⅡ) and Losartan on the expression of connective tissue growth factor (CTGF) mRNA in cultured mesangial cells (MCs). Methods MCs of SD rats were isolated and cultured. High glucose (30 mmol/L) and AngⅡ (10-9, 10 7, and 10-5 mol/L) were added to the medium for 72 hours to observe the influence on CTGF mRNA expression. Losartan of 10-5 mol/L and AngⅡ of 10-5 mol/L were added to the medium to observe the effects of Losartan on CTGF mRNA expression stimulated by AngⅡ. The expressions of CTGF mRNA were detected by reverse transcriptase polymerase chain reaction (RT-PCR).Results RT-PCR showed that high glucose and AngⅡ up-regulated the expression of CTGF mRNA, and AngⅡ stimulated the expression in a dose-dependent manner. Expression of CTGF mRNA induced by AngⅡwas partially suppressed by 10-5mol/L Losartan (P<0.05).Conclusions High glucose and AngⅡ can enhance the expression of CTGF mRNA and thus be involved in the process of renal fibrosis. Losartan can have a partial fibrogenesis-inhibiting effect, with implications for the treatment of renal fibrosis.

  14. Sequence variation in the androgen receptor gene is not a common determinant of male sexual orientation.

    OpenAIRE

    Macke, J. P.; Hu, N; S. Hu; Bailey, M.; King, V L; Brown, T.; Hamer, D; Nathans, J

    1993-01-01

    To test the hypothesis that DNA sequence variation in the androgen receptor gene plays a causal role in the development of male sexual orientation, we have (1) measured the degree of concordance of androgen receptor alleles in 36 pairs of homosexual brothers, (2) compared the lengths of polyglutamine and polyglycine tracts in the amino-terminal domain of the androgen receptor in a sample of 197 homosexual males and 213 unselected subjects, and (3) screened the the entire androgen receptor cod...

  15. Tales of one gene discovery of a novel candidate receptor in mammalian taste

    OpenAIRE

    Huang, Angela Lilly

    2007-01-01

    There are five basic taste modalities in mammals: bitter, sweet, sour, salty, and Umami (taste of MSG and L-amino acids). Receptors for bitter, sweet, and Umami were previously discovered. Identities of receptors for salty and sour taste modalities remained elusive. In this dissertation, I will present: 1) development of a novel bioinformatics screen to discover candidate receptors; 2) discovery of a novel gene, PKD2L1, in taste receptor cells; 3) evidence demonstrating PKD2L1-expressing tast...

  16. Differential localization and characterization of functional calcitonin gene-related peptide receptors in human subcutaneous arteries

    DEFF Research Database (Denmark)

    Edvinsson, L; Ahnstedt, H; Larsen, R;

    2014-01-01

    Calcitonin gene-related peptide (CGRP) and its receptor are widely distributed within the circulation and the mechanism behind its vasodilation not only differs from one animal species to another but is also dependent on the type and size of vessel. The present study examines the nature of CGRP......-induced vasodilation, characteristics of the CGRP receptor antagonist telcagepant and localization of the key components calcitonin receptor-like receptor (CLR) and receptor activity modifying protein 1 (RAMP1) of the CGRP receptor in human subcutaneous arteries....

  17. Massive Losses of Taste Receptor Genes in Toothed and Baleen Whales

    OpenAIRE

    Feng, Ping; Zheng, Jinsong; Rossiter, Stephen J.; WANG, DING; Zhao, Huabin

    2014-01-01

    Taste receptor genes are functionally important in animals, with a surprising exception in the bottlenose dolphin, which shows extensive losses of sweet, umami, and bitter taste receptor genes. To examine the generality of taste gene loss, we examined seven toothed whales and five baleen whales and sequenced the complete repertoire of three sweet/umami (T1Rs) and ten bitter (T2Rs) taste receptor genes. We found all amplified T1Rs and T2Rs to be pseudogenes in all 12 whales, with a shared prem...

  18. Expression of androgen receptor target genes in skeletal muscle

    Institute of Scientific and Technical Information of China (English)

    Kesha Rana; Nicole KL Lee; Jeffrey D Zajac; Helen E MacLean

    2014-01-01

    We aimed to determine the mechanisms of the anabolic actions of androgens in skeletal muscle by investigating potential androgen receptor(AR)‑regulated genes ininvitroandinvivomodels. The expression of the myogenic regulatory factormyogenin was signiifcantly decreased in skeletal muscle from testosterone‑treated orchidectomized male mice compared to control orchidectomized males, and was increased in muscle from male AR knockout mice that lacked DNA binding activity(ARΔZF2) versus wildtype mice, demonstrating thatmyogenin is repressed by the androgen/AR pathway. The ubiquitin ligaseFbxo32 was repressed by 12h dihydrotestosterone treatment in human skeletal muscle cell myoblasts, andc‑Myc expression was decreased in testosterone‑treated orchidectomized male muscle compared to control orchidectomized male muscle, and increased in AR∆ZF2 muscle. The expression of a group of genes that regulate the transition from myoblast proliferation to differentiation, Tceal7, p57Kip2, Igf2 andcalcineurin Aa, was increased in AR∆ZF2 muscle, and the expression of all butp57Kip2was also decreased in testosterone‑treated orchidectomized male muscle compared to control orchidectomized male muscle. We conclude that in males, androgens act via the AR in part to promote peak muscle mass by maintaining myoblasts in the proliferative state and delaying the transition to differentiation during muscle growth and development, and by suppressing ubiquitin ligase‑mediated atrophy pathways to preserve muscle mass in adult muscle.

  19. Association of Interleukin-4 Receptor Gene Polymorphism with Chronic Periodontitis

    Directory of Open Access Journals (Sweden)

    M. Khoshhal

    2011-10-01

    Full Text Available Introduction & Objective: Periodontitis is a multifactorial disease in which host immune system and genetic factors have an important role in its pathogenesis. Genetic polymorphisms in cytokines and their receptors have been proposed as potential markers for periodontal diseases. The aim of the present study was to evaluate whether IL-4R gene polymorphism is associated with chronic periodontitis (CP or not? Materials & Methods: In this cross sectional study ninety non smoker patients (61 women and 29 men with chronic periodontitis were selected according to established criteria. They were categorized into three groups according to their clinical attachment level (CAL. Mutation at position 375(alanine/glutamine, 411(leucine/serine, 478(serine/proline, 406 (arginine/ cysteine in the IL-4R gene was detected by a polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLP method.Results: The distribution of mutations for IL-4 polymorphism at amino acids 375 (P=0.41, 411(P=0.22, 478(P=0.17, 406(P=0.77 were not significantly different among mild, moderate and sever chronic periodontitis patients. Conclusion: This study suggests that there is no correlation between IL-4R polymorphism of chronic periodontitis.(Sci J Hamadan Univ Med Sci 2011;18(3:63-69

  20. Melanocortin-1 receptor gene variants in four Chinese ethnic populations

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    There is strong relationship between melanocortin-1 receptor (MC1R) gene variants and human hair color and skin type.Based on a sequencing study of MC1R gene in 50 individuals from the Uygur,Tibetan,Wa and Dai ethnic populations,we discuss the occurrence of 7 mc1r variants consisting of 5 nonsynonymous sites (Val60Leu,Arg67Gln,Val92Met,Arg163Gln and Ala299Val) and 2 synonymous sites (C414T and A942G),among which C414T and Ala299Val were reported for the first time.Confirmation and analysis were also made of 122 individuals at three common point mutations (Val92Met,Arg163Gln,A942G) using PCR-SSCP.The frequency of Arg163Gln variant varies in the four ethnic populations,with percentage of 40%,85.0%,66.2% and 72.7%,respectively,while those of Val92Met and A942G are roughly similar in these four populations.The different environments,migration and admixture of various ethnic groups in China might have impact on the observed frequency of Arg163Gln.

  1. Activation of transforming potential of the human insulin receptor gene

    International Nuclear Information System (INIS)

    A retrovirus containing part of the human insulin receptor (hIR) gene was constructed by replacing ros sequences in the avian sarcoma virus UR2 with hIR cDNA sequences coding for 46 amino acids of the extracellular domain and the entire transmembrane and cytoplasmic domains of the β subunit of hIR. The resulting virus, named UIR, contains the hIR sequence fused to the 5' portion of the UR2 gag gene coding for p19. UIR is capable of transforming chicken embryo fibroblasts and promoting formation of colonies in soft agar; however, it does not form tumors in vivo. A variant that arose from the parental UIR is capable of efficiently inducing sarcomas in vivo. UIR-transformed cells exhibit higher rates of glucose uptake and growth than normal cells. The 4-kilobase UIR genome codes for a membrane-associated, glycosylated gag-hIR fusion protein of 75 kDa designated P75/sup gag-hir/. P75/sup gag-hir/ contains a protein tyrosine kinase activity that is capable of undergoing autophosphorylation and of phosphorylating foreign substrates in vitro; it is phosphorylated at both serine and tyrosine residues in vivo

  2. Activation of transforming potential of the human insulin receptor gene

    Energy Technology Data Exchange (ETDEWEB)

    Wang, L.H.; Lin, B.; Jong, S.M.J.; Dixon, D.; Ellis, L.; Roth, R.A.; Rutter, W.J.

    1987-08-01

    A retrovirus containing part of the human insulin receptor (hIR) gene was constructed by replacing ros sequences in the avian sarcoma virus UR2 with hIR cDNA sequences coding for 46 amino acids of the extracellular domain and the entire transmembrane and cytoplasmic domains of the ..beta.. subunit of hIR. The resulting virus, named UIR, contains the hIR sequence fused to the 5' portion of the UR2 gag gene coding for p19. UIR is capable of transforming chicken embryo fibroblasts and promoting formation of colonies in soft agar; however, it does not form tumors in vivo. A variant that arose from the parental UIR is capable of efficiently inducing sarcomas in vivo. UIR-transformed cells exhibit higher rates of glucose uptake and growth than normal cells. The 4-kilobase UIR genome codes for a membrane-associated, glycosylated gag-hIR fusion protein of 75 kDa designated P75/sup gag-hir/. P75/sup gag-hir/ contains a protein tyrosine kinase activity that is capable of undergoing autophosphorylation and of phosphorylating foreign substrates in vitro; it is phosphorylated at both serine and tyrosine residues in vivo

  3. Expression of androgen receptor target genes in skeletal muscle

    Directory of Open Access Journals (Sweden)

    Kesha Rana

    2014-10-01

    Full Text Available We aimed to determine the mechanisms of the anabolic actions of androgens in skeletal muscle by investigating potential androgen receptor (AR-regulated genes in in vitro and in vivo models. The expression of the myogenic regulatory factor myogenin was significantly decreased in skeletal muscle from testosterone-treated orchidectomized male mice compared to control orchidectomized males, and was increased in muscle from male AR knockout mice that lacked DNA binding activity (ARΔZF2 versus wildtype mice, demonstrating that myogenin is repressed by the androgen/AR pathway. The ubiquitin ligase Fbxo32 was repressed by 12 h dihydrotestosterone treatment in human skeletal muscle cell myoblasts, and c-Myc expression was decreased in testosterone-treated orchidectomized male muscle compared to control orchidectomized male muscle, and increased in AR∆ZF2 muscle. The expression of a group of genes that regulate the transition from myoblast proliferation to differentiation, Tceal7 , p57 Kip2, Igf2 and calcineurin Aa, was increased in AR∆ZF2 muscle, and the expression of all but p57 Kip2 was also decreased in testosterone-treated orchidectomized male muscle compared to control orchidectomized male muscle. We conclude that in males, androgens act via the AR in part to promote peak muscle mass by maintaining myoblasts in the proliferative state and delaying the transition to differentiation during muscle growth and development, and by suppressing ubiquitin ligase-mediated atrophy pathways to preserve muscle mass in adult muscle.

  4. Leptin receptor gene polymorphisms in severely pre-eclamptic women.

    Science.gov (United States)

    Rigó, János; Szendei, György; Rosta, Klára; Fekete, Andrea; Bögi, Krisztina; Molvarec, Attila; Rónai, Zsolt; Vér, Agota

    2006-09-01

    Variants of the leptin receptor gene (LEPR) may modulate the effect of elevated serum leptin levels in pre-eclampsia. The aim of our study was to evaluate the LEPR gene polymorphisms Lys109Arg (A109G) and Gln223Arg (A223G) in severely pre-eclamptic women. In a case-control study, we analyzed blood samples from 124 severely pre-eclamptic patients and 107 healthy control women by the polymerase chain reaction-restriction fragment length polymorphism method. The Pearson chi2 test was used to estimate odds ratios (OR) and 95% confidence intervals (CI). The association was adjusted for maternal age, pre-pregnancy body mass index and primiparity with logistic regression analysis. Pregnant women with the LEPR 223G allele (223A/G or 223G/G genotype) had almost double the risk of developing severe pre-eclampsia compared with patients with the 223A/A genotype (adjusted OR = 1.92, 95% CI: 1.07-3.41). Genotype variants of LEPR A109G alone did not affect the risk of severe pre-eclampsia. Haplotype estimation of A109G and A223G polymorphisms of the LEPR gene revealed that the G-A haplotype versus other pooled haplotypes was significantly less common in the pre-eclamptic group (p < 0.01), while the G-G haplotype versus others was overrepresented among severely pre-eclamptic patients (p < 0.01), compared with controls. In conclusion, our data indicate that LEPR A223G polymorphism may individually modify the risk of severe pre-eclampsia. PMID:17071538

  5. Association of vitamin D receptor gene variants with polycystic ovary syndrome: A case control study

    OpenAIRE

    Touraj Mahmoudi; Keivan Majidzadeh-A; Hamid Farahani; Mojgan Mirakhorli; Reza Dabiri; Hossein Nobakht; Asadollah Asadi

    2015-01-01

    Background: Vitamin D and insulin play an important role in susceptibility to polycystic ovary syndrome (PCOS), and therefore vitamin D receptor (VDR), parathyroid hormone (PTH), and insulin receptor (INSR) gene variants might be involved in the pathogenesis of PCOS. Objective: The present study was designed to investigate the possible associations between polymorphisms in VDR, PTH, and INSR genes and the risk of PCOS. Materials and Methods: VDR, PTH, and INSR gene variants were genoty...

  6. Association of vitamin D receptor gene variants with polycystic ovary syndrome: A case control study

    OpenAIRE

    Mahmoudi, Touraj; Majidzadeh-A, Keivan; Farahani, Hamid; Mirakhorli, Mojgan; Dabiri, Reza; Nobakht, Hossein; Asadi, Asadollah

    2015-01-01

    Background: Vitamin D and insulin play an important role in susceptibility to polycystic ovary syndrome (PCOS), and therefore vitamin D receptor (VDR), parathyroid hormone (PTH), and insulin receptor (INSR) gene variants might be involved in the pathogenesis of PCOS. Objective: The present study was designed to investigate the possible associations between polymorphisms in VDR, PTH, and INSR genes and the risk of PCOS. Materials and Methods: VDR, PTH, and INSR gene variants were genotyped in ...

  7. Functional Characterization of Soybean Glyma04g39610 as a Brassinosteroid Receptor Gene and Evolutionary Analysis of Soybean Brassinosteroid Receptors

    Science.gov (United States)

    Peng, Suna; Tao, Ping; Xu, Feng; Wu, Aiping; Huo, Weige; Wang, Jinxiang

    2016-01-01

    Brassinosteroids (BR) play important roles in plant growth and development. Although BR receptors have been intensively studied in Arabidopsis, the BR receptors in soybean remain largely unknown. Here, in addition to the known receptor gene Glyma06g15270 (GmBRI1a), we identified five putative BR receptor genes in the soybean genome: GmBRI1b, GmBRL1a, GmBRL1b, GmBRL2a, and GmBRL2b. Analysis of their expression patterns by quantitative real-time PCR showed that they are ubiquitously expressed in primary roots, lateral roots, stems, leaves, and hypocotyls. We used rapid amplification of cDNA ends (RACE) to clone GmBRI1b (Glyma04g39160), and found that the predicted amino acid sequence of GmBRI1b showed high similarity to those of AtBRI1 and pea PsBRI1. Structural modeling of the ectodomain also demonstrated similarities between the BR receptors of soybean and Arabidopsis. GFP-fusion experiments verified that GmBRI1b localizes to the cell membrane. We also explored GmBRI1b function in Arabidopsis through complementation experiments. Ectopic over-expression of GmBRI1b in Arabidopsis BR receptor loss-of-function mutant (bri1-5 bak1-1D) restored hypocotyl growth in etiolated seedlings; increased the growth of stems, leaves, and siliques in light; and rescued the developmental defects in leaves of the bri1-6 mutant, and complemented the responses of BR biosynthesis-related genes in the bri1-5 bak1-D mutant grown in light. Bioinformatics analysis demonstrated that the six BR receptor genes in soybean resulted from three gene duplication events during evolution. Phylogenetic analysis classified the BR receptors in dicots and monocots into three subclades. Estimation of the synonymous (Ks) and the nonsynonymous substitution rate (Ka) and selection pressure (Ka/Ks) revealed that the Ka/Ks of BR receptor genes from dicots and monocots were less than 1.0, indicating that BR receptor genes in plants experienced purifying selection during evolution. PMID:27338344

  8. Expression of glucocorticoid and progesterone nuclear receptor genes in archival breast cancer tissue

    International Nuclear Information System (INIS)

    Previous studies in our laboratory have shown associations of specific nuclear receptor gene variants with sporadic breast cancer. In order to investigate these findings further, we conducted the present study to determine whether expression levels of the progesterone and glucocorticoid nuclear receptor genes vary in different breast cancer grades. RNA was extracted from paraffin-embedded archival breast tumour tissue and converted into cDNA. Sample cDNA underwent PCR using labelled primers to enable quantitation of mRNA expression. Expression data were normalized against the 18S ribosomal gene multiplex and analyzed using analysis of variance. Analysis of variance indicated a variable level of expression of both genes with regard to breast cancer grade (P = 0.00033 for glucocorticoid receptor and P = 0.023 for progesterone receptor). Statistical analysis indicated that expression of the progesterone nuclear receptor is elevated in late grade breast cancer tissue

  9. Early pharmacological inhibition of angiotensin-I converting enzyme activity induces obesity in adulthood

    Directory of Open Access Journals (Sweden)

    Kely ede Picoli Souza

    2015-04-01

    Full Text Available We have investigated early programming of body mass in order to understand the multifactorial etiology of obesity. Considering that the renin-angiotensin system is expressed and functional in the white adipose tissue (WAT and modulates its development, we reasoned whether early transitory inhibition of angiotensin-I converting enzyme activity after birth could modify late body mass development. Therefore, newborn Wistar rats were treated with enalapril (10 mg/kg of body mass or saline, starting at the first day of life until the age of 16 days. Between days 90th and 180th, a group of these animals received high fat diet (HFD. Molecular, biochemical, histological and physiological data were collected. Enalapril treated animals presented hyperphagia, overweight and increased serum level of triglycerides, total cholesterol and leptin, in adult life. Body composition analyses revealed higher fat mass with increased adipocyte size in these animals. Molecular analyses revealed that enalapril treatment increases neuropeptide Y (NPY and cocaine- and amphetamine-regulated transcript (CART gene expression in hypothalamus, fatty acid synthase (FAS and hormone-sensitive lipase (HSL gene expression in retroperitoneal WAT and decreases peroxixome proliferators-activated receptor (PPAR γ, PPARα, uncoupling protein (UCP 2 and UCP3 gene expression in WAT. The results of the current study indicate that enalapril administration during early postnatal development increases body mass, adiposity and serum lipids in adulthood associated with enhanced food intake and decreased metabolic activity in WAT, predisposing to obesity in adulthood.

  10. Evolution of Dopamine Receptor Genes of the D1 Class in Vertebrates

    OpenAIRE

    Yamamoto, Kei(Department of Physics, Niigata University, Niigata 950-2181, Japan); Mirabeau, Olivier; Bureau, Charlotte; Blin, Maryline; Michon-Coudouel, Sophie; Demarque, Michaël; Vernier, Philippe

    2012-01-01

    The receptors of the dopamine neurotransmitter belong to two unrelated classes named D1 and D2. For the D1 receptor class, only two subtypes are found in mammals, the D1A and D1B, receptors, whereas additional subtypes, named D1C, D1D, and D1X, have been found in other vertebrate species. Here, we analyzed molecular phylogeny, gene synteny, and gene expression pattern of the D1 receptor subtypes in a large range of vertebrate species, which leads us to propose a new view of the evolution of D...

  11. Identification of Modulators of the Nuclear Receptor Peroxisome Proliferator-Activated Receptor α (PPARα) in a Mouse Liver Gene Expression Compendium

    Science.gov (United States)

    The nuclear receptor family member peroxisome proliferator-activated receptor α (PPARα) is activated by therapeutic hypolipidemic drugs and environmentally-relevant chemicals to regulate genes involved in lipid transport and catabolism. Chronic activation of PPARα in rodents inc...

  12. Increased perfusion pressure enhances the expression of endothelin (ETB) and angiotensin II (AT1, AT2) receptors in rat mesenteric artery smooth muscle cells

    DEFF Research Database (Denmark)

    Lindstedt, Isak; Xu, Cang-Bao; Zhang, Yaping;

    2009-01-01

    In the present study, we hypothesized that changes in perfusion pressure result in altered expression of mRNA and protein encoding for the ETA-, ETB-, AT1- and AT2-receptors in rat mesenteric vessels. Segments of the rat mesenteric artery were cannulated with glass micropipettes, pressurized and...

  13. Rational design, efficient syntheses and biological evaluation of N,N '-symmetrically bis-substituted butylimidazole analogs as a new class of potent Angiotensin II receptor blockers

    Czech Academy of Sciences Publication Activity Database

    Agelis, G.; Resvani, A.; Koukoulitsa, C.; Tůmová, Tereza; Slaninová, Jiřina; Kalavrizioti, D.; Spyridaki, K.; Afantitis, A.; Melagraki, G.; Siafaka, A.; Gkini, E.; Megariotis, G.; Grdadolnik, S. G.; Papadopoulos, M. G.; Vlahakos, D.; Maragoudakis, M.; Liapakis, G.; Mavromoustakos, T.; Matsoukas, J.

    2013-01-01

    Roč. 62, Apr (2013), s. 352-370. ISSN 0223-5234 Institutional support: RVO:61388963 Keywords : AT1 receptor blockers * N,N '-Bis-alkylated butylimidazole analogs * synthesis * Wittig reaction * hydroxymethylation * structure elucidation Subject RIV: CC - Organic Chemistry Impact factor: 3.432, year: 2013

  14. Angiotensin II type 1 receptors stimulate protein synthesis in human cardiac fibroblasts via a Ca2+-sensitive PKC-dependent tyrosine kinase pathway

    DEFF Research Database (Denmark)

    Hou, M; Pantev, E; Möller, S;

    2000-01-01

    ) was obtained at a concentration of 10 nM. There were no significant alterations of cell number or total protein content, suggesting that Ang II stimulated protein synthesis but did not induce hypertrophy. The accumulation of 3H-leucine was blocked by the AT1 receptor antagonist candesartan but not by...

  15. Genomic organization of the human thyroid hormone receptor alpha (c-erbA-1) gene.

    OpenAIRE

    Laudet, V; Begue, A; Henry-Duthoit, C; Joubel, A; P. Martin; Stehelin, D.; Saule, S.

    1991-01-01

    The thyroid hormone receptor alpha (THRA or c-erbA-1) gene belongs to a family of genes which encode nuclear receptors for various hydrophobic ligands such as steroids, vitamin D, retinoic acid and thyroid hormones. These receptors are composed of several domains important for hormone-binding, DNA-binding, dimerization and activation of transcription. We show here that the human THRA gene is organized in 10 exons distributed along 27 kbp of genomic DNA on chromosome 17. The position of the in...

  16. Differential regulation of interleukin-8 gene transcription by death receptor 3 (DR3) and type I TNF receptor (TNFRI).

    Science.gov (United States)

    Su, Wenlynn B; Chang, Ying-Hsin; Lin, Wan-Wan; Hsieh, Shie-Liang

    2006-02-01

    TL1A induces interleukin-8 (IL-8) secretion in human peripheral blood monocyte-derived macrophage in a dose- and time-dependent manner. Overexpression of its cognate receptor DR3 can induce a higher amount of IL-8 protein secretion than that induced by TNFRI even though both receptors activate IL-8 gene transcription in a similar fashion. The underlying mechanism for the regulation of the IL-8 gene transcription by DR3 has not been investigated yet. Here, we used HEK293 cells as a model system to dissect the possible signaling components that are involved in the regulation of DR3-mediated IL-8 gene expression. Although both DR3 and TNFRI activated TRAF2 and NF-kappaB to induce IL-8 gene transcription, the kinase cascades that transduce signals for DR3- and TNFRI-induced IL-8 gene transcription are different. The axis TAK1/ASK1-MKK4/MKK7-JNK2 is responsible for DR3-mediated IL-8 gene expression whereas the axis ASK1-MKK4-JNK1/JNK2/p38MAPK is the choice for TNFRI-mediated activation of IL-8 gene expression. This indicates that the downstream signaling pathways of DR3 and TNFRI for IL-8 secretion are divergent even though both receptors contain death-domain and induce IL-8 secretion via TRAF2. PMID:16324699

  17. Penguins reduced olfactory receptor genes common to other waterbirds

    Science.gov (United States)

    Lu, Qin; Wang, Kai; Lei, Fumin; Yu, Dan; Zhao, Huabin

    2016-01-01

    The sense of smell, or olfaction, is fundamental in the life of animals. However, penguins (Aves: Sphenisciformes) possess relatively small olfactory bulbs compared with most other waterbirds such as Procellariiformes and Gaviiformes. To test whether penguins have a reduced reliance on olfaction, we analyzed the draft genome sequences of the two penguins, which diverged at the origin of the order Sphenisciformes; we also examined six closely related species with available genomes, and identified 29 one-to-one orthologous olfactory receptor genes (i.e. ORs) that are putatively functionally conserved and important across the eight birds. To survey the 29 one-to-one orthologous ORs in penguins and their relatives, we newly generated 34 sequences that are missing from the draft genomes. Through the analysis of totaling 378 OR sequences, we found that, of these functionally important ORs common to other waterbirds, penguins have a significantly greater percentage of OR pseudogenes than other waterbirds, suggesting a reduction of olfactory capability. The penguin-specific reduction of olfactory capability arose in the common ancestor of penguins between 23 and 60 Ma, which may have resulted from the aquatic specializations for underwater vision. Our study provides genetic evidence for a possible reduction of reliance on olfaction in penguins. PMID:27527385

  18. Effects of angiotensin II on visual neurons in the superficial laminae of the hamster's superior colliculus.

    Science.gov (United States)

    Mooney, R D; Zhang, Y; Rhoades, R W

    1994-01-01

    Superficial layer superior colliculus (SC) neurons were recorded extracellularly with multibarreled recording/ejecting micropipettes. Angiotensin II was delivered via micropressure ejection during visual stimulation (n = 215 cells), or during electrical stimulation of either the optic chiasm (OX; n = 150 cells) or visual cortex (CTX; n = 42 cells). Application of angiotensin II decreased visual responses of SC cells to 43.8% +/- 30.7% (mean +/- S.D.) and reduced responses to electrical stimulation of the OX and CTX to 58.6% +/- 34.1% and 43.8% +/- 30.7% of control values, respectively. Angiotensin II enhanced responses by at least 30% in only 6 cells (1.5%). Of the 35 neurons tested with both OX and CTX stimulation, the correlation of evoked response suppression by angiotensin II was highly significant (r = 0.69; P iontophoresis of glutamate and then tested with angiotensin II. Angiotensin II reduced the glutamate-evoked responses to an average 29.1% +/- 21.1% of control values (n = 9 cells). This suggest that the site of action of angiotensin II is most likely postsynaptic. To identify which receptors were involved in these effects, angiotensin II was ejected concurrently with the AT1 antagonist Losartan (DUP753) or with either of two AT2 antagonists, CGP42112A or PD123177. Losartan antagonized the action of angiotensin II in 65.6% of the cells tested (n = 99) and CGP42112A and PD123177 had antagonistic effects in 58% (n = 65) and 60% (n = 5), respectively. Both classes of antagonists were tested in 29 cells; and there was no significant correlation between their effectiveness. These results suggest that both AT1 and AT2 receptors may independently mediate the suppressive effects of angiotensin II, and that collicular neurons may have either or both receptor subtypes. PMID:7841124

  19. Family structure and phylogenetic analysis of odorant receptor genes in the large yellow croaker (Larimichthys crocea

    Directory of Open Access Journals (Sweden)

    Zhu Peng

    2011-08-01

    Full Text Available Abstract Background Chemosensory receptors, which are all G-protein-coupled receptors (GPCRs, come in four types: odorant receptors (ORs, vomeronasal receptors, trace-amine associated receptors and formyl peptide receptor-like proteins. The ORs are the most important receptors for detecting a wide range of environmental chemicals in daily life. Most fish OR genes have been identified from genome databases following the completion of the genome sequencing projects of many fishes. However, it remains unclear whether these OR genes from the genome databases are actually expressed in the fish olfactory epithelium. Thus, it is necessary to clone the OR mRNAs directly from the olfactory epithelium and to examine their expression status. Results Eighty-nine full-length and 22 partial OR cDNA sequences were isolated from the olfactory epithelium of the large yellow croaker, Larimichthys crocea. Bayesian phylogenetic analysis classified the vertebrate OR genes into two types, with several clades within each type, and showed that the L. crocea OR genes of each type are more closely related to those of fugu, pufferfish and stickleback than they are to those of medaka, zebrafish and frog. The reconciled tree showed 178 duplications and 129 losses. The evolutionary relationships among OR genes in these fishes accords with their evolutionary history. The fish OR genes have experienced functional divergence, and the different clades of OR genes have evolved different functions. The result of real-time PCR shows that different clades of ORs have distinct expression levels. Conclusion We have shown about 100 OR genes to be expressed in the olfactory epithelial tissues of L. crocea. The OR genes of modern fishes duplicated from their common ancestor, and were expanded over evolutionary time. The OR genes of L. crocea are closely related to those of fugu, pufferfish and stickleback, which is consistent with its evolutionary position. The different expression

  20. Anti-atherosclerotic effects of an angiotensin converting enzyme inhibitor and an angiotensin II antagonist in Cynomolgus monkeys fed a high-cholesterol diet

    OpenAIRE

    Miyazaki, Mizuo; Sakonjo, Hiroshi; Takai, Shinji

    1999-01-01

    We investigated the relationship between angiotensin II formation and the development of atherosclerotic lesions in the aorta of monkeys (Macaca fascicularis) fed a high-cholesterol (4% cholesterol and 6% corn oil) diet for 6 months, and studied the effects of an angiotensin converting enzyme (ACE) inhibitor, trandolapril (10 mg kg−1 per day, p.o.), and an angiotensin II type 1 receptor antagonist, 2-butyl-4-(methylthio)-1-[[2′[[[(propylamino)carbonyl]amino]sulfonyl](1,1′-biphenyl)-4-yl]methy...

  1. Inhibition of oxytocin-induced but not angiotensin-induced rat uterine contractions following exposure to sodium sulfide

    Energy Technology Data Exchange (ETDEWEB)

    Hayden, L.J.; Franklin, K.J.; Roth, S.H.; Moore, G.J. (Univ. of Calgary, Alberta (Canada))

    1989-01-01

    Low concentrations of sodium sulfide reversibly attenuate the contractile response of the isolate rat uterus to oxytocin without affecting angiotensin II responsiveness. These findings suggest that functionally important disulfide bonds in the rat uterine oxytocin receptor, but not the angiotensin receptor, are sensitive to hydrosulfide ion. Reduction of oxytocin receptors by hydrosulfide ion may be a mechanism by which low level of H{sub 2}S delay parturition in rats.

  2. Elevated AT1 receptor protein but lower angiotensin II-binding in adipose tissue of rats with monosodium glutamate-induced obesity

    Czech Academy of Sciences Publication Activity Database

    Pinterová, L.; Železná, Blanka; Ficková, M.; Macho, L.; Križanová, O.; Ježová, D.; Zórad, Š.

    2001-01-01

    Roč. 33, č. 12 (2001), s. 708-12. ISSN 0018-5043 R&D Projects: GA ČR GA204/99/1453 Grant ostatní: VEGA(SK) VEGA 2/7213; VEGA(SK) VEGA 2/6084; VEGA(SK) VEGA 2/7158 Keywords : AT1 receptor * fat tissue * MSG rat Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition Impact factor: 1.910, year: 2001

  3. A Peroxisome Proliferator-Activated Receptor-α Activator Induces Renal CYP2C23 Activity and Protects from Angiotensin II-Induced Renal Injury

    OpenAIRE

    Muller, Dominik N.; Theuer, Juergen; Shagdarsuren, Erdenechimeg; Kaergel, Eva; Honeck, Horst; Park, Joon-Keun; Markovic , Marija; Barbosa-Sicard, Eduardo; Dechend, Ralf; Wellner, Maren; Kirsch, Torsten; Fiebeler, Anette; Rothe, Michael; Haller, Hermann; Luft, Friedrich C.

    2004-01-01

    Cytochrome P450 (CYP)-dependent arachidonic acid (AA) metabolites are involved in the regulation of renal vascular tone and salt excretion. The epoxygenation product 11,12-epoxyeicosatrienoic acid (EET) is anti-inflammatory and inhibits nuclear factor-κB activation. We tested the hypothesis that the peroxisome proliferator-activated receptor-α-activator fenofibrate (Feno) induces CYP isoforms, AA hydroxylation, and epoxygenation activity, and protects against inflammatory organ damage. Double...

  4. Upregulation of AT2 receptor and iNOS impairs angiotensin II-induced contraction without endothelium influence in young normotensive diabetic rats

    OpenAIRE

    Lee, Jin Hee; Xia, Shichao; Ragolia, Louis

    2008-01-01

    Diabetes and insulin resistance are associated with an increased risk of hypertension and cardiovascular disease. Recent evidence demonstrates that AT2 receptors (AT2R) play an important role in the hemodynamic control of hypertension by vasodilation. The quantitative significance of AT2R in the establishment of diabetic vascular dysfunction, however, is not well defined and needs further investigation. Goto-Kakizaki (GK) rats, a polygenic model of spontaneous normotensive type 2 diabetes, we...

  5. Increased perfusion pressure enhances the expression of endothelin (ETB) and angiotensin II (AT1, AT2) receptors in rat mesenteric artery smooth muscle cells

    DEFF Research Database (Denmark)

    Lindstedt, Isak; Xu, Cang-Bao; Zhang, Yaping;

    2009-01-01

    In the present study, we hypothesized that changes in perfusion pressure result in altered expression of mRNA and protein encoding for the ETA-, ETB-, AT1- and AT2-receptors in rat mesenteric vessels. Segments of the rat mesenteric artery were cannulated with glass micropipettes, pressurized and...... luminally perfused in a perfusion chamber. After either exposure to no ("organ culture" (0 mmHg)), normal (85/75 mmHg) or high pressure (160/150 mmHg) at constant flow for 1-17 h, the vessel segments were snap frozen and real-time polymerase chain reaction was performed to quantify the ET- and AT-receptor m......RNA content, or immersed in a fixative solution, dehydrated, frozen, cut in a cryostat and immunohistology stained for ET- and AT-receptor protein. The mRNA expressions of ETB and of AT2 were significantly enhanced in vessels exposed to high perfusion pressure, compared with normal and no perfusion pressure...

  6. A mutation in the DNA-binding domain of the androgen receptor gene causes complete testicular feminization in a patient with receptor-positive androgen resistance.

    OpenAIRE

    M. Marcelli; Zoppi, S; Grino, P B; Griffin, J E; Wilson, J. D.; McPhaul, M J

    1991-01-01

    Androgen resistance is associated with a wide range of quantitative and qualitative defects in the androgen receptor. However, fibroblast cultures from approximately 10% of patients with the clinical, endocrine, and genetic features characteristic of androgen resistance express normal quantities of apparently normal androgen receptor in cultured genital skin fibroblasts (receptor-positive androgen resistance). We have analyzed the androgen receptor gene of one patient (P321) with receptor-pos...

  7. Impact of The Protective Renin-Angiotensin System (RAS) on The Vasoreparative Function of CD34+ CACs in Diabetic Retinopathy

    Science.gov (United States)

    Duan, Yaqian; Moldovan, Leni; Miller, Rehae C.; Beli, Eleni; Salazar, Tatiana; Hazra, Sugata; Al-Sabah, Jude; Chalam, KV; Raghunandan, Sneha; Vyas, Ruchi; Parsons-Wingerter, Patricia; Oudit, Gavin Y.; Grant, Maria B.

    2016-01-01

    Purpose: In diabetes, the impaired vasoreparative function of Circulating Angiogenic Cells (CACs) is believed to contribute to the progression of diabetic retinopathy (DR). Accumulating evidence suggests that the protective arm of renin-angiotensin system (RAS) ACE2 Angiotensin-(1-7) Mas plays an important role in restoring the function of diabetic CACs. We examined the protective RAS in CACs in diabetic individuals with different stages of retinopathy. Methods: Study subjects (n43) were recruited as controls or diabetics with either no DR, mild non-proliferative DR (NPDR), moderate NPDR, severe NPDR or proliferative DR (PDR). Fundus photography and fluorescein angiograms were analyzed using Vessel Generation Analysis (VESGEN) software in a cohort of subjects. CD34+ CACs were isolated from peripheral blood of diabetics and control subjects. RAS gene expressions in CACs were measured by qPCR. The vasoreparative function of CACs was assessed by migration ability toward CXCL12 using the QCM 5M 96-well chemotaxis cell migration assay. Results: ACE2 gene is a key enzyme converting the deleterious Angiotensin II to the beneficial Angiotensin-(1-7). ACE2 expression in CACs from diabetic subjects without DR was increased compared to controls, suggestive of compensation (p0.0437). The expression of Mas (Angiotensin-(1-7) receptor) in CACs was also increased in diabetics without DR, while was reduced in NPDR compared to controls (p0.0002), indicating a possible loss of compensation of the protective RAS at this stage of DR. The presence of even mild NPDR was associated with CD34+ CAC migratory dysfunction. When pretreating CACs of DR subjects with Angiotensin-(1-7), migratory ability to a chemoattractant CXCL12 was restored (p0.0008). By VESGEN analysis, an increase in small vessel density was observed in NPDR subjects when compared with the controls. Conclusions: These data suggest the protective RAS axis within diabetic CACs may help maintain their vasoreparative potential

  8. Test of Association Between 10 SNPs in the Oxytocin Receptor Gene and Conduct Disorder

    OpenAIRE

    Sakai, Joseph T.; Crowley, Thomas J.; Stallings, Michael C.; McQueen, Matthew; Hewitt, John K.; Hopfer, Christian; Hoft, Nicole R.; Ehringer, Marissa A.

    2012-01-01

    Animal and human studies have implicated oxytocin (OXT) in affiliative and prosocial behaviors. We tested whether genetic variation in the OXT receptor (OXTR) gene is associated with conduct disorder (CD).

  9. Interaction effects between estrogen receptor α and vitamin D receptor genes on age at menarche in Chinese women

    Institute of Scientific and Technical Information of China (English)

    Hong XU; Ji-rong LONG; Miao-xin LI; Hong-wen DENG

    2005-01-01

    Aim: To evaluate whether estrogen receptor α (ER-α) and vitamin D receptor (VDR) genes are associated with the age at menarche in Chinese women.Methods:A total of 390 pre-menopausal Chinese women were genotyped at the ER-α PvuⅡ,XbaⅠ, and VDR ApaⅠ loci using polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP).Results: Neither the ER-α gene nor the VDR gene individually had significant effects on the age at menarche in our subjects (P>0.10).However, evidence of interaction effects between the two genes were observed: with the aa genotype at the VDR ApaⅠ locus, subjects with haplotype PX at the ER-α gene had, on average, 6 months later onset of menarche than the non-carriers (P=0.01).Conclusion: We found that neither the ER-α gene or the VDR gene had a significant association with the age at menarche individually.However, potential interaction effects between the two genes were observed in Chinese women.

  10. Toll-like receptor 4 gene polymorphism is associated with chronic periodontitis

    OpenAIRE

    Ding, Yuan-Sheng; Zhao, Yue; Xiao,Yuan-Yuan; Zhao, Gang

    2015-01-01

    Toll-like receptors (TLRs) contribute to the immune response by recognizing patterns presented by bacteria and other pathogens. These receptors have been implicated in the inflammatory response that contributes to gingivitis and periodontitis. Conflicting reports have suggested that variations in the genes encoding TLRs, particularly TLR2 and TLR4, may influence susceptibility to periodontitis. In this study, the contribution of variations in the genes encoding TLR2 and TLR4 in the context of...

  11. Common Oxytocin Receptor Gene Polymorphisms and the Risk for Preterm Birth

    OpenAIRE

    Lorenz Kuessel; Christoph Grimm; Martin Knöfler; Peter Haslinger; Heinz Leipold; Georg Heinze; Christian Egarter; Maximilian Schmid

    2013-01-01

    Oxytocin is crucially involved in the onset and maintenance of labor. We investigated the association between oxytocin receptor gene polymorphisms and preterm birth. The presence of four common oxytocin receptor gene polymorphisms (rs2254298, rs53576, rs2228485 and rs237911) was evaluated in one hundred women with preterm birth and one hundred healthy women using restriction fragment length polymorphism genotyping. No association was found between the presence of any individual oxytocin recep...

  12. Osteoblast-Specific Transcription Factor Osterix Increases Vitamin D Receptor Gene Expression in Osteoblasts

    OpenAIRE

    Zhang, Chi; Tang, Wanjin; LI Yang; Yang, Fan; Dowd, Diane R.; MacDonald, Paul N.

    2011-01-01

    Osterix (Osx) is an osteoblast-specific transcription factor required for osteoblast differentiation from mesenchymal stem cells. In Osx knock-out mice, no bone formation occurs. The vitamin D receptor (VDR) is a member of the nuclear hormone receptor superfamily that regulates target gene transcription to ensure appropriate control of calcium homeostasis and bone development. Here, we provide several lines of evidence that show that the VDR gene is a target for transcriptional regulation by ...

  13. In vitro biliary clearance of angiotensin II receptor blockers and 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors in sandwich-cultured rat hepatocytes: comparison with in vivo biliary clearance.

    Science.gov (United States)

    Abe, Koji; Bridges, Arlene S; Yue, Wei; Brouwer, Kim L R

    2008-09-01

    Previous reports have indicated that in vitro biliary clearance (Cl(biliary)) determined in sandwich-cultured hepatocytes correlates well with in vivo Cl(biliary) for limited sets of compounds. This study was designed to estimate the in vitro Cl(biliary) in sandwich-cultured rat hepatocytes (SCRHs) of angiotensin II receptor blockers and HMG-CoA reductase inhibitors that undergo limited metabolism, to compare the estimated Cl(biliary) values with published in vivo Cl(biliary) data in rats, and to characterize the mechanism(s) of basolateral uptake and canalicular excretion of these drugs in rats. The average biliary excretion index (BEI) and in vitro Cl(biliary) values of olmesartan, valsartan, pravastatin, rosuvastatin, and pitavastatin were 15, 19, 43, 45, and 20%, respectively, and 1.7, 3.2, 4.4, 46.1, and 34.6 ml/min/kg, respectively. Cl(biliary) predicted from SCRHs, accounting for plasma unbound fraction, correlated with reported in vivo Cl(biliary) for these drugs. The rank order of Cl(biliary) values predicted from SCRHs was consistent with in vivo Cl(biliary) values. Bromosulfophthalein inhibited the uptake of all drugs. BEI and Cl(biliary) values of olmesartan, valsartan, pravastatin, and rosuvastatin, known multidrug resistance-associated protein (Mrp) 2 substrates, were reduced in SCRHs from Mrp2-deficient (TR(-)) compared with wild-type (WT) rats. Although Mrp2 plays a minor role in pitavastatin biliary excretion, pitavastatin BEI and Cl(biliary) were reduced in TR(-) compared with WT SCRHs; Bcrp expression in SCRHs from TR(-) rats was decreased. In conclusion, in vitro Cl(biliary) determined in SCRHs can be used to estimate and compare in vivo Cl(biliary) of compounds in rats and to characterize transport proteins responsible for their hepatic uptake and excretion. PMID:18574002

  14. A comparison between diuretics and angiotensin-receptor blocker agents in patients with stage I hypertension (PREVER-treatment trial: study protocol for a randomized double-blind controlled trial

    Directory of Open Access Journals (Sweden)

    Figueiredo Neto José A

    2011-02-01

    Full Text Available Abstract Background Cardiovascular disease is the leading cause of death in Brazil, and hypertension is its major risk factor. The benefit of its drug treatment to prevent major cardiovascular events was consistently demonstrated. Angiotensin-receptor blockers (ARB have been the preferential drugs in the management of hypertension worldwide, despite the absence of any consistent evidence of advantage over older agents, and the concern that they may be associated with lower renal protection and risk for cancer. Diuretics are as efficacious as other agents, are well tolerated, have longer duration of action and low cost, but have been scarcely compared with ARBs. A study comparing diuretic and ARB is therefore warranted. Methods/design This is a randomized, double-blind, clinical trial, comparing the association of chlorthalidone and amiloride with losartan as first drug option in patients aged 30 to 70 years, with stage I hypertension. The primary outcomes will be variation of blood pressure by time, adverse events and development or worsening of microalbuminuria and of left ventricular hypertrophy in the EKG. The secondary outcomes will be fatal or non-fatal cardiovascular events: myocardial infarction, stroke, heart failure, evidence of new subclinical atherosclerosis and sudden death. The study will last 18 months. The sample size will be of 1200 participants for group in order to confer enough power to test for all primary outcomes. The project was approved by the Ethics committee of each participating institution. Discussion The putative pleiotropic effects of ARB agents, particularly renal protection, have been disputed, and they have been scarcely compared with diuretics in large clinical trials, despite that they have been at least as efficacious as newer agents in managing hypertension. Even if the null hypothesis is not rejected, the information will be useful for health care policy to treat hypertension in Brazil. Clinical trials

  15. Short and Long-Term Effects of the Angiotensin II Receptor Blocker Irbesartan on Intradialytic Central Hemodynamics: A Randomized Double-Blind Placebo-Controlled One-Year Intervention Trial (the SAFIR Study.

    Directory of Open Access Journals (Sweden)

    Christian Daugaard Peters

    Full Text Available Little is known about the tolerability of antihypertensive drugs during hemodialysis treatment. The present study evaluated the use of the angiotensin II receptor blocker (ARB irbesartan.Randomized, double-blind, placebo-controlled, one-year intervention trial.Eighty-two hemodialysis patients with urine output >300 mL/day and dialysis vintage <1 year.Irbesartan/placebo 300 mg/day for 12 months administered as add-on to antihypertensive treatment using a predialytic systolic blood pressure target of 140 mmHg in all patients.Cardiac output, stroke volume, central blood volume, total peripheral resistance, mean arterial blood pressure, and frequency of intradialytic hypotension.At baseline, the groups were similar regarding age, comorbidity, blood pressure, antihypertensive medication, ultrafiltration volume, and dialysis parameters. Over the one-year period, predialytic systolic blood pressure decreased significantly, but similarly in both groups. Mean start and mean end cardiac output, stroke volume, total peripheral resistance, heart rate, and mean arterial pressure were stable and similar in the two groups, whereas central blood volume increased slightly but similarly over time. The mean hemodynamic response observed during a dialysis session was a drop in cardiac output, in stroke volume, in mean arterial pressure, and in central blood volume, whereas heart rate increased. Total peripheral resistance did not change significantly. Overall, this pattern remained stable over time in both groups and was uninfluenced by ARB treatment. The total number of intradialytic hypotensive episodes was (placebo/ARB 50/63 (P = 0.4. Ultrafiltration volume, left ventricular mass index, plasma albumin, and change in intradialytic total peripheral resistance were significantly associated with intradialytic hypotension in a multivariate logistic regression analysis based on baseline parameters.Use of the ARB irbesartan as an add-on to other antihypertensive

  16. Role of angiotensin AT2 receptors and nitric oxide in the cardiopulmonary baroreflex control of renal sympathetic nerve activity in anaesthetised rats

    OpenAIRE

    Abdulla, Mohammed H.; Johns, Edward J.

    2013-01-01

    This study investigated the role of AT2 receptor activation and the possible interaction with nitric oxide (NO) in low-pressure baroreceptor regulation of renal sympathetic nerve activity (RSNA). Renal sympatho-inhibition to a saline volume expansion (VEP, 0.25% bwt/min I.V. for 30 min) was studied following intracerebroventricular (i.c.v.) saline, CGP42112 (CGP, AT2 agonist), PD123319 (PD, AT2 antagonist) and losartan (AT1 antagonist), and then in combination with L-NAME (NO synthase inhibit...

  17. Computational characterization of modes of transcriptional regulation of nuclear receptor genes.

    Directory of Open Access Journals (Sweden)

    Yogita Sharma

    Full Text Available BACKGROUND: Nuclear receptors are a large structural class of transcription factors that act with their co-regulators and repressors to maintain a variety of biological and physiological processes such as metabolism, development and reproduction. They are activated through the binding of small ligands, which can be replaced by drug molecules, making nuclear receptors promising drug targets. Transcriptional regulation of the genes that encode them is central to gaining a deeper understanding of the diversity of their biochemical and biophysical roles and their role in disease and therapy. Even though they share evolutionary history, nuclear receptor genes have fundamentally different expression patterns, ranging from ubiquitously expressed to tissue-specific and spatiotemporally complex. However, current understanding of regulation in nuclear receptor gene family is still nascent. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we investigate the relationship between long-range regulation of nuclear receptor family and their known functionality. Towards this goal, we identify the nuclear receptor genes that are potential targets based on counts of highly conserved non-coding elements. We validate our results using publicly available expression (RNA-seq and histone modification (ChIP-seq data from the ENCODE project. We find that nuclear receptor genes involved in developmental roles show strong evidence of long-range mechanism of transcription regulation with distinct cis-regulatory content they feature clusters of highly conserved non-coding elements distributed in regions spanning several Megabases, long and multiple CpG islands, bivalent promoter marks and statistically significant higher enrichment of enhancer mark around their gene loci. On the other hand nuclear receptor genes that are involved in tissue-specific roles lack these features, having simple transcriptional controls and a greater variety of mechanisms for producing paralogs. We

  18. The PGE(2)-EP4 receptor is necessary for stimulation of the renin-angiotensin-aldosterone system in response to low dietary salt intake in vivo

    DEFF Research Database (Denmark)

    Pöschke, Antje; Kern, Niklas; Maruyama, Takayuki; Pavenstädt, Hermann; Narumiya, Shuh; Jensen, Boye L; Nüsing, Rolf M

    2012-01-01

    (+/+), EP4(-/-), and in wild-type mice treated with EP4 receptor antagonist. After 2 wk of a low-salt diet (0.02% wt/wt NaCl), EP4(+/+) mice showed diminished Na(+) excretion, unchanged K(+) excretion, and reduced Ca(2+) excretion. Diuresis and plasma electrolytes remained unchanged. EP4(-/-) exhibited a......, creatinine clearance, and plasma antidiuretic hormone (ADH) concentration. Following salt restriction, plasma renin and aldosterone concentrations and kidney renin mRNA level rose significantly in EP4(+/+) but not in EP4(-/-) and in wild-type mice treated with EP4 antagonist ONO-AE3-208. In the latter two......Increased cyclooxygenase-2 (COX-2) expression and PGE(2) synthesis have been shown to be prerequisites for renal renin release after Na(+) deprivation. To answer the question of whether EP4 receptor type of PGE(2) mediates renin regulation under a low-salt diet, we examined renin regulation in EP4...

  19. Molecular Pathways: Breaking the Epithelial Cancer Barrier for Chimeric Antigen Receptor and T-cell Receptor Gene Therapy.

    Science.gov (United States)

    Hinrichs, Christian S

    2016-04-01

    Adoptive transfer of T cells genetically engineered to express a tumor-targeting chimeric antigen receptor (CAR) or T-cell receptor (TCR) can mediate cancer regression in some patients. CARs are synthetic single-chain proteins that use antibody domains to target cell surface antigens. TCRs are natural heterodimeric proteins that can target intracellular antigens through recognition of peptides bound to human leukocyte antigens. CARs have shown promise in B-cell malignancies and TCRs in melanoma, but neither approach has achieved clear success in an epithelial cancer. Treatment of epithelial cancers may be particularly challenging because of a paucity of target antigens expressed by carcinomas and not by important healthy tissues. In addition, epithelial cancers may be protected by inhibitory ligands and soluble factors in the tumor microenvironment. One strategy to overcome these negative regulators is to modulate expression of T-cell genes to enhance intrinsic T-cell function. Programmable nucleases, which can suppress inhibitory genes, and inducible gene expression systems, which can enhance stimulatory genes, are entering clinical testing. Other work is delineating whether control of genes for immune checkpoint receptors (e.g.,PDCD1, CTLA4) and cytokine and TCR signaling regulators (e.g.,CBLB, CISH, IL12, IL15) can increase the antitumor activity of therapeutic T cells.Clin Cancer Res; 22(7); 1559-64. ©2016 AACR. PMID:27037253

  20. Evolutionary patterns and selective pressures of odorant/pheromone receptor gene families in teleost fishes.

    Directory of Open Access Journals (Sweden)

    Yasuyuki Hashiguchi

    Full Text Available BACKGROUND: Teleost fishes do not have a vomeronasal organ (VNO, and their vomeronasal receptors (V1Rs, V2Rs are expressed in the main olfactory epithelium (MOE, as are odorant receptors (ORs and trace amine-associated receptors (TAARs. In this study, to obtain insights into the functional distinction among the four chemosensory receptor families in teleost fishes, their evolutionary patterns were examined in zebrafish, medaka, stickleback, fugu, and spotted green pufferfish. METHODOLOGY/PRINCIPAL FINDINGS: Phylogenetic analysis revealed that many lineage-specific gene gains and losses occurred in the teleost fish TAARs, whereas only a few gene gains and losses have taken place in the teleost fish vomeronasal receptors. In addition, synonymous and nonsynonymous nucleotide substitution rate ratios (K(A/K(S in TAARs tended to be higher than those in ORs and V2Rs. CONCLUSIONS/SIGNIFICANCE: Frequent gene gains/losses and high K(A/K(S in teleost TAARs suggest that receptors in this family are used for detecting some species-specific chemicals such as pheromones. Conversely, conserved repertoires of V1R and V2R families in teleost fishes may imply that receptors in these families perceive common odorants for teleosts, such as amino acids. Teleost ORs showed intermediate evolutionary pattern between TAARs and vomeronasal receptors. Many teleost ORs seem to be used for common odorants, but some ORs may have evolved to recognize lineage-specific odors.