RESUMEN
In a physiological context, the extracellular matrix (ECM) provides an important scaffold for organs. Dysregulation of ECM in disease conditions, characterised by excess deposition of connective tissue and extracellular matrix in response to a pathological insult, is a key driver of disease progression in multiple organs. The resultant fibrosis is predominantly an irreversible process and directly contributes to, and exacerbates, dysfunction of an affected organ. This is particularly paramount in the kidney, liver, heart and lung. A hybrid Joint Meeting of NC-IUPHAR and British Pharmacological Society was held in Paris and via a webinar in November 2020, when two successive sessions were devoted to translational advances in fibrosis as a therapeutic target. On the upsurge of response to these sessions, the concept of a special themed issue on this topic emerged, and is entitled Translational Advances in Fibrosis as a Therapeutic Target. In this special issue, we seek to provide an up-to-date account of the diverse molecular mechanisms and causal role that fibrosis plays in disease progression (contributing to, and exacerbating, dysfunction of affected organs). Recent developments in the understanding of molecular targets involved in fibrosis, and how their actions can be manipulated therapeutically, are included. LINKED ARTICLES: This article is part of a themed issue on Translational Advances in Fibrosis as a Therapeutic Target. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v180.22/issuetoc.
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Matriz Extracelular , Corazón , Humanos , Fibrosis , Progresión de la EnfermedadRESUMEN
Urotensin II (UII) is a cyclic neuropeptide that was first isolated from the urophysis of teleost fish on the basis of its ability to contract the hindgut. Subsequently, UII was characterized in tetrapods including humans. Phylogenetic studies and synteny analysis indicate that UII and its paralogous peptide urotensin II-related peptide (URP) belong to the somatostatin/cortistatin superfamily. In mammals, the UII and URP genes are primarily expressed in cholinergic neurons of the brainstem and spinal cord. UII and URP mRNAs are also present in various organs notably in the cardiovascular, renal, and endocrine systems. UII and URP activate a common G protein-coupled receptor, called UT, that exhibits relatively high sequence identity with somatostatin, opioid, and galanin receptors. The UT gene is widely expressed in the central nervous system (CNS) and in peripheral tissues including the retina, heart, vascular bed, lung, kidney, adrenal medulla, and skeletal muscle. Structure-activity relationship studies and NMR conformational analysis have led to the rational design of a number of peptidic and nonpeptidic UT agonists and antagonists. Consistent with the wide distribution of UT, UII has now been shown to exert a large array of biologic activities, in particular in the CNS, the cardiovascular system, and the kidney. Here, we review the current knowledge concerning the pleiotropic actions of UII and discusses the possible use of antagonists for future therapeutic applications.
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Hormonas Peptídicas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Urotensinas/metabolismo , Secuencia de Aminoácidos , Animales , Antagonistas de Hormonas/farmacología , Humanos , Péptidos y Proteínas de Señalización Intracelular , Ligandos , Datos de Secuencia Molecular , Hormonas Peptídicas/antagonistas & inhibidores , Hormonas Peptídicas/química , Hormonas Peptídicas/genética , Conformación Proteica , Receptores Acoplados a Proteínas G/antagonistas & inhibidores , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/genética , Transducción de Señal , Relación Estructura-Actividad , Urotensinas/antagonistas & inhibidores , Urotensinas/química , Urotensinas/genéticaRESUMEN
BACKGROUND: ß-Adrenoceptor agonists are effective in animal models of bladder dysfunction, and the human bladder primarily expresses the ß3 receptor subtype. OBJECTIVE: To evaluate the efficacy and tolerability of the highly selective and potent ß3-adrenoceptor agonist solabegron in a clinical proof-of-concept study in incontinent women with overactive bladder (OAB). DESIGN, SETTING, AND PARTICIPANTS: This was a randomized, double-blind trial in adult women with OAB (one or more 24-h incontinence episodes and eight or more average 24-h micturitions). INTERVENTIONS: Solabegron 50 mg (n=88), solabegron 125 mg (n=85), or placebo (n=85)-all twice daily-were administered. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary efficacy end point was percentage change from baseline to week 8 in the number of incontinence episodes over 24 h. Secondary end points included actual change and percentage change from baseline to week 4 and week 8 in micturitions per 24 h, urgency episodes per 24 h, and volume voided per micturition. Adverse events (AEs) were assessed, as well. RESULTS AND LIMITATIONS: Solabegron 125 mg produced a statistically significant difference in percent change from baseline to week 8 in incontinence episodes over 24h when compared with placebo (p=0.025). Solabegron 125 mg treatment also showed statistically significant reductions from baseline to weeks 4 and 8 in micturitions over 24 h and a statistically significant increase from baseline to week 8 in urine volume voided. Solabegron was well tolerated, with a similar incidence of AEs in each treatment group. There were no significant treatment differences for mean changes from baseline to week 8 in systolic blood pressure (BP), diastolic BP, mean arterial pressure (MAP), or heart rate during the 24-h ambulatory measurement. CONCLUSIONS: Solabegron significantly reduced the symptoms of OAB in women with moderate to severe OAB. Solabegron was safe, well tolerated, and did not demonstrate significant differences in AEs as compared to placebo. ß3-Adrenoceptor agonists may represent a new therapeutic approach for treating OAB symptoms.
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Agonistas de Receptores Adrenérgicos beta 3/uso terapéutico , Compuestos de Anilina/uso terapéutico , Benzoatos/uso terapéutico , Compuestos de Bifenilo/uso terapéutico , Vejiga Urinaria Hiperactiva/tratamiento farmacológico , Vejiga Urinaria/efectos de los fármacos , Incontinencia Urinaria/tratamiento farmacológico , Agonistas de Receptores Adrenérgicos beta 3/administración & dosificación , Agonistas de Receptores Adrenérgicos beta 3/efectos adversos , Adulto , Anciano , Compuestos de Anilina/administración & dosificación , Compuestos de Anilina/efectos adversos , Argentina , Australia , Benzoatos/administración & dosificación , Benzoatos/efectos adversos , Compuestos de Bifenilo/administración & dosificación , Compuestos de Bifenilo/efectos adversos , Método Doble Ciego , Esquema de Medicación , Europa (Continente) , Femenino , Humanos , Modelos Lineales , Persona de Mediana Edad , Nueva Zelanda , República de Corea , Sudáfrica , Taiwán , Factores de Tiempo , Resultado del Tratamiento , Vejiga Urinaria/fisiopatología , Vejiga Urinaria Hiperactiva/fisiopatología , Incontinencia Urinaria/fisiopatología , Micción/efectos de los fármacos , Urodinámica/efectos de los fármacos , Adulto JovenRESUMEN
RATIONALE: Expression of the vasoactive peptide Urotensin II (UII) is elevated in a number of cardiovascular diseases. OBJECTIVE: Here, we sought to determine the effect of UII receptor (UT) gene deletion in a mouse model of atherosclerosis. METHODS AND RESULTS: UT knockout (KO) mice were crossed with ApoE KO mice to generate UT/ApoE double knockout (DKO) mice. Mice were placed on a high-fat Western-type diet for 12 weeks. We evaluated the degree of atherosclerosis and hepatic steatosis by histology. In addition, serum glucose, insulin, and lipids were determined. DKO mice exhibited significantly increased atherosclerosis compared to ApoE KO mice (P<0.05). This was associated with a significant increase in serum insulin and lipids (P<0.001) but a decrease in hepatic steatosis (P<0.001). UT gene deletion led to a significant increase in systolic pressure and pulse pressure. RT-PCR and immunoblot analyses showed significant reductions in hepatic scavenger receptors, nuclear receptors, and acyl-CoA:cholesterol acyltransferase (ACAT1) expression in DKO mice. UII induced a significant increase in intracellular cholesteryl ester formation in primary mouse hepatocytes, which was blocked by the MEK inhibitor, PD98059. Hepatocytes of UTKO mice showed a significant reduction in lipoprotein uptake compared to wild-type mice. CONCLUSIONS: We propose that UT gene deletion in an ApoE-deficient background promotes downregulation of ACAT1, which in turn attenuates hepatic lipoprotein receptor-mediated uptake and lipid transporter expression. As the liver is the main organ for uptake of lipoprotein-derived lipids, DKO leads to an increase in hyperlipidemia, with a concomitant decrease in hepatic steatosis, and consequently increased atherosclerotic lesion formation. Furthermore, the hypertension associated with UT gene deletion is likely to contribute to the increased atherosclerotic burden.
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Aorta/metabolismo , Apolipoproteínas E/deficiencia , Aterosclerosis/metabolismo , Hiperlipidemias/metabolismo , Hígado/metabolismo , Receptores Acoplados a Proteínas G/deficiencia , Urotensinas/metabolismo , Acetil-CoA C-Acetiltransferasa/metabolismo , Animales , Aorta/efectos de los fármacos , Aorta/patología , Apolipoproteínas E/genética , Aterosclerosis/genética , Aterosclerosis/patología , Aterosclerosis/fisiopatología , Glucemia/metabolismo , Presión Sanguínea , Células Cultivadas , Ésteres del Colesterol/metabolismo , Grasas de la Dieta/administración & dosificación , Modelos Animales de Enfermedad , Hígado Graso/metabolismo , Hígado Graso/prevención & control , Genotipo , Hiperlipidemias/genética , Hiperlipidemias/patología , Hiperlipidemias/fisiopatología , Insulina/sangre , Lípidos/sangre , Hígado/efectos de los fármacos , Hígado/patología , Macrófagos Peritoneales/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Fenotipo , Inhibidores de Proteínas Quinasas/farmacología , Receptores Citoplasmáticos y Nucleares/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Depuradores/metabolismo , Factores de TiempoRESUMEN
Urotensin II (UII) and its receptor UT are upregulated in the pathological setting of various cardiovascular diseases including atherosclerosis. However, their exact role in atherosclerosis remains to be determined. In the present study we used four strains of mice; wild-type (WT), UT(+) (a transgenic strain expressing human UT driven by the alpha-smooth muscle-specific, SM22, promoter), ApoE knockout (ko), and UT(+)/ApoE ko. All animals were fed high fat diet for 12 weeks. Western blot analysis revealed a significant increase in aortic UT expression in UT(+) relative to WT mice (P<0.05). Aortas of ApoE ko mice expressed comparable UT protein level to that of UT(+). Immunohistochemistry revealed the presence of strong expression of UT and UII proteins in the atheroma of UT(+), ApoE ko and UT(+)/ApoE ko mice, particularly in foam cells. Serum cholesterol and triglyceride levels were significantly increased in ApoE ko and in UT(+)/ApoE ko but not in UT(+) mice when compared to WT mice (P<0.0001). Analysis of aortas showed a significant increase in atherosclerotic lesion in the UT(+), ApoE ko and UT(+)/ApoE ko compared to WT mice (P<0.05). Oral administration of the UT receptor antagonist SB-657510A (30 microg/Kg/day gavage) for 10 weeks in a group of ApoE ko mice fed on high fat diet resulted in a significant reduction of lesion (P<0.001). SB-657510A also significantly reduced ACAT-1 protein expression in the atherosclerotic lesion of ApoE ko mice (P<0.05). The present findings demonstrate an important role for UT in the pathogenesis of atherosclerosis. The use of UT receptor antagonists may provide a beneficial tool in the management of this debilitating disease process.
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Enfermedades de la Aorta/prevención & control , Apolipoproteínas E/deficiencia , Aterosclerosis/prevención & control , Fármacos Cardiovasculares/farmacología , Músculo Liso Vascular/efectos de los fármacos , Miocitos del Músculo Liso/efectos de los fármacos , Receptores Acoplados a Proteínas G/antagonistas & inhibidores , Sulfonamidas/farmacología , Acetil-CoA C-Acetiltransferasa/metabolismo , Animales , Aorta/efectos de los fármacos , Aorta/metabolismo , Enfermedades de la Aorta/genética , Enfermedades de la Aorta/metabolismo , Enfermedades de la Aorta/patología , Apolipoproteínas E/genética , Aterosclerosis/genética , Aterosclerosis/metabolismo , Aterosclerosis/patología , Western Blotting , Colesterol en la Dieta/sangre , Modelos Animales de Enfermedad , Células Espumosas/metabolismo , Humanos , Inmunohistoquímica , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Proteínas de Microfilamentos/genética , Proteínas Musculares/genética , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patología , Miocitos del Músculo Liso/metabolismo , Miocitos del Músculo Liso/patología , Regiones Promotoras Genéticas , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Triglicéridos/sangre , Urotensinas/metabolismoRESUMEN
The IUPHAR database (IUPHAR-DB) integrates peer-reviewed pharmacological, chemical, genetic, functional and anatomical information on the 354 nonsensory G protein-coupled receptors (GPCRs), 71 ligand-gated ion channel subunits and 141 voltage-gated-like ion channel subunits encoded by the human, rat and mouse genomes. These genes represent the targets of approximately one-third of currently approved drugs and are a major focus of drug discovery and development programs in the pharmaceutical industry. IUPHAR-DB provides a comprehensive description of the genes and their functions, with information on protein structure and interactions, ligands, expression patterns, signaling mechanisms, functional assays and biologically important receptor variants (e.g. single nucleotide polymorphisms and splice variants). In addition, the phenotypes resulting from altered gene expression (e.g. in genetically altered animals or in human genetic disorders) are described. The content of the database is peer reviewed by members of the International Union of Basic and Clinical Pharmacology Committee on Receptor Nomenclature and Drug Classification (NC-IUPHAR); the data are provided through manual curation of the primary literature by a network of over 60 subcommittees of NC-IUPHAR. Links to other bioinformatics resources, such as NCBI, Uniprot, HGNC and the rat and mouse genome databases are provided. IUPHAR-DB is freely available at http://www.iuphar-db.org.
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Bases de Datos de Proteínas , Canales Iónicos/genética , Canales Iónicos/fisiología , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/fisiología , Animales , Descubrimiento de Drogas , Humanos , Canales Iónicos/química , Ligandos , Ratones , Subunidades de Proteína/química , Subunidades de Proteína/genética , Subunidades de Proteína/fisiología , Ratas , Receptores Acoplados a Proteínas G/químicaRESUMEN
Peroxisome proliferator-activated receptor (PPAR)-delta is a transcription factor that belongs to the PPAR family. PPAR-delta is abundantly expressed in the heart, and its role in the heart is largely unknown. We tested whether pharmacological activation of PPAR-delta protects the heart from ischemia/reperfusion (I/R) injury in male Zucker fatty rats, a rodent model of obesity and dyslipidemia. A highly selective PPAR-delta agonist, [4-[[[2-[3-fluoro-4-(trifluoromethyl)phenyl]-4-methyl-5-thiazolyl]methyl] thio]-2-methylphenoxy]acetic acid (GW0742), was administered for 7 days at 10 mg/kg/day (p.o., once a day). Ischemic injury was produced by occlusion of the left anterior descending artery for 30 min followed by reperfusion for up to 24 h. Treatment with GW0742 reduced serum levels of cardiac troponin-I and infarct size by 63% (p < 0.01) and 32% (p < 0.01), respectively, and improved left ventricular function. Treatment with GW0742 up-regulated gene expression involved in cardiac fatty acid oxidation, increased fat use in the heart, and reduced serum levels of free fatty acids. The enhanced cardiac expression of interleukin (IL)-6, IL-8, intercellular adhesion molecule-1, and monocyte chemoattractant protein-1 induced by I/R were significantly attenuated by GW0742. Treatment with GW0742 also reduced apoptotic cardiomyocytes by 34% and cardiac caspase-3 activity by 61% (both p < 0.01 versus vehicle). GW0742 differentially regulated Bcl family members, favoring cell survival, and attenuated I/R-induced cardiac mitochondrial damage. In addition, GW0742 treatment augmented the cardiac Akt signaling pathway, as reflected by enhanced phospho-3-phosphoinositide-dependent kinase-1 and p-Akt. The results indicate that activation of PPAR-delta protected the heart from I/R injury in Zucker fatty rats, and multiple mechanisms including amelioration of lipotoxicity, anti-inflammation, and up-regulation of prosurvival signaling contribute together to the cardioprotection.
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Cardiotónicos/uso terapéutico , Daño por Reperfusión Miocárdica/prevención & control , PPAR delta/agonistas , Tiazoles/uso terapéutico , Animales , Presión Sanguínea/efectos de los fármacos , Citocinas/genética , Modelos Animales de Enfermedad , Ácidos Grasos/sangre , Ácidos Grasos/metabolismo , Corazón/fisiopatología , Cetonas/metabolismo , Masculino , Síndrome Metabólico/sangre , Síndrome Metabólico/fisiopatología , Daño por Reperfusión Miocárdica/sangre , Daño por Reperfusión Miocárdica/fisiopatología , PPAR delta/fisiología , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Mensajero/metabolismo , Ratas , Ratas Zucker , Troponina I/sangreRESUMEN
BACKGROUND/AIMS: Histological studies have provided evidence that carvedilol can prevent cardiac hypertrophy in spontaneously hypertensive-stroke prone rats (SP) fed a high-fat and -salt diet. However, the effects of carvedilol on cardiac function have not been studied in these animals. In addition, the ability of carvedilol to reverse established cardiac hypertrophy and dysfunction under these conditions remains to be determined. Here we have evaluated the ability of carvedilol to prevent and reverse cardiac hypertrophy and progressive dysfunction using echocardiography. METHODS: Two echocardiology studies were conducted to determine the effects of carvedilol treatment on cardiac hypertrophy and dysfunction. In the first prevention study, four groups of rats were evaluated. SP were fed a high-fat (24.5% in food) and high-salt (1% in water) diet (SFD) without (SP-SFD control group) or with carvedilol (SP-SFD carvedilol group; carvedilol concentration 2,400 parts per million) for 18 weeks. Carvedilol was administered in the food at an optimum concentration (i.e. known to provide clinically relevant blood concentrations and reduce cardiac hypertrophy determined from previous studies). In addition, SP and WKY rats were fed a normal diet (SP normal diet group and WKY normal diet group). These groups are known to not develop the same significant cardiac hypertrophy and dysfunction within this limited time of study, and provided two more normal control groups for comparison. In the second reversal study, one group of SP was fed SFD for 12 weeks (SP-SFD pretreatment period) to induce cardiac hypertrophy. Carvedilol (2,400 parts per million) was then added to the diet for an additional 6 weeks (SP-SFD carvedilol treatment period). RESULTS: In the first prevention study, carvedilol prolonged longevity (p < 0.05) and prevented left-ventricular hypertrophy and dysfunction (p < 0.05; SP-SFD control vs. SP-SFD carvedilol group). M-mode-measured and -calculated parameters demonstrated that carvedilol treatment in the SP-SFD carvedilol group prevented increases in left-ventricular wall thickness (p < 0.05) and decreases in diastolic chamber diameter and volume, stroke volume, ejection fraction and cardiac output (all p < 0.05) that occurred in the SP-SFD control group. Further, cardiac measurements in the SP-SFD carvedilol group were normalized to levels similar to those in the SP and WKY normal diet groups. All SFD-fed groups exhibited similar, significantly elevated blood pressure during the study. In the second reversal study, carvedilol treatment for 6 weeks reversed the cardiac hypertrophy and dysfunction that developed in SP-fed SFD for 12 weeks prior to carvedilol intervention. Under these conditions, carvedilol improved/normalized left-ventricular wall thickness, diastolic ventricular-chamber diameter and volume, stroke volume, ejection fraction and cardiac output (all p < 0.05). CONCLUSIONS: These data indicate that carvedilol provides protection from and facilitates reversal of progressive cardiac remodeling and dysfunction in this SP-SFD model of cardiac hypertrophy/heart failure. Since these effects occurred in the absence of effects on blood pressure, other known actions of carvedilol, especially its antioxidant activity, for example, may explain this significant cardiac protection. In addition, research using this SP-SFD model of cardiac hypertrophy/end-organ injury appears to translate well to human cardiovascular disease.
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Antagonistas Adrenérgicos beta/farmacología , Antioxidantes/farmacología , Carbazoles/farmacología , Cardiomegalia/prevención & control , Propanolaminas/farmacología , Vasodilatadores/farmacología , Administración Oral , Animales , Cardiomegalia/diagnóstico por imagen , Cardiomegalia/fisiopatología , Carvedilol , Dieta , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Masculino , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY , Resultado del Tratamiento , Ultrasonografía , Remodelación Ventricular/efectos de los fármacosRESUMEN
Treatment for symptomatic atherosclerosis is being carried out by balloon mediated angioplasty, with or without stent implantation, more and more frequently. Although advances with the development of drug eluting stents have improved prognosis, restenosis is still the most limiting factor for this treatment modality. Urotensin-II (UII), a small pleiotropic vasoactive peptide is increasingly being recognized as a contributory factor in cardiovascular diseases. We qualitatively evaluated UII immunoreactivity (IR) in three models of balloon angioplasty mediated restenosis. Specifically, we performed balloon angioplasty in the ilio-femoral arteries of New Zealand White Rabbits (NZWR) fed either a normal chow or high fat diet. In addition, UIIIR was also assessed in stent implanted abdominal aortae of NZWR fed a high fat diet. UII was constitutively expressed in the endothelium of all arterial segments evaluated. Abundant expression of UII was associated with lesion progression, particularly in myointimal cells, and less so in medial smooth muscle cells (SMC). The strongest UII-IR was observed in foam cells of animals fed a high fat diet. We demonstrate abundant expression of UII in regenerating endothelial cells and myointimal cells in vascular lesions following balloon mediated angioplasty and stent implantation in both animals fed a normal chow and high fat diet.
RESUMEN
It is now well established that urotensin-II (UII) levels are increased in several cardiovascular diseases. We previously demonstrated that UII and the UII receptor (UT) protein levels are significantly increased in the hearts of both humans and rats with congestive heart failure (CHF). We have also recently demonstrated that UII blockade, with a selective UII antagonist, improves heart function in a rat model of ischemic CHF. Here, we evaluated the attenuation of cardiac remodeling associated with UII antagonism in the same rat model of ischemic CHF. Animals were administered a specific UT receptor antagonist, SB-611812 (30 mg/kg/day, gavage), or vehicle 30 min prior to coronary artery ligation followed by daily treatment for 8 weeks. Myocardial interstitial fibrosis was analyzed by Masson's trichrome and picrosirius red staining. RT-PCR analysis was utilized for mRNA expression studies. We used Western blotting to assess levels of collagen types I and III. Mitogenic activity of UII on cultured neonatal cardiac fibroblasts was also evaluated. Following coronary ligation, SB-611812 significantly attenuated both myocardial and endocardial interstitial fibrosis, and reduced collagen type I:III ratio (P<0.01). UII induced proliferation of cardiac fibroblasts and this mitogenic effect was significantly inhibited with 1 microM of SB-611218 (P<0.05). We demonstrate here that selective blockade of UT reduces diastolic dysfunction by decreasing myocardial fibrosis post-coronary ligation in vivo, and inhibits UII-mediated fibroblast proliferation in vitro.
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Isquemia Miocárdica/tratamiento farmacológico , Isquemia Miocárdica/fisiopatología , Receptores Acoplados a Proteínas G/antagonistas & inhibidores , Sulfonamidas/farmacología , Remodelación Ventricular/efectos de los fármacos , Animales , Células Cultivadas , Modelos Animales de Enfermedad , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Fibrosis/patología , Fibrosis/prevención & control , Perfilación de la Expresión Génica , Masculino , Isquemia Miocárdica/patología , Miocardio/patología , Ratas , Ratas Endogámicas Lew , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Urotensinas/farmacologíaRESUMEN
Expression of urotensin II (UII) is significantly elevated in the hearts of patients with congestive heart failure (CHF). Recent reports have also shown increased plasma levels of UII in patients with CHF, and these levels correlated with the severity of disease. We therefore hypothesized that blockade of UII signaling would improve cardiac function in a rat model of CHF. CHF was induced in rats by ligating the left coronary artery. Animals were randomized to either treatment with a specific UT receptor antagonist, SB-611812 (30 mg/kg/day, UID by gavage), or vehicle, starting either 30 min prior to coronary ligation (early treatment) or 10 days after ligation (delayed treatment). Treatment drug or vehicle was administered daily thereafter for 8 weeks. We measured cardiac function and evaluated the levels of mRNA expression for mediators of CHF. In addition, we evaluated UII and UT protein levels using immunohistochemistry and Western blotting. Cardiomyocyte hypertrophy was evaluated by measuring cardiomyocyte cross-sectional area. Animals with CHF showed increased UII and UT expression as evidenced by immunohistochemistry and Western blotting. Treatment with the SB-611812 significantly reduced overall mortality, left ventricular end-diastolic pressure by 72%, lung edema by 71%, right ventricular systolic pressure by 92%, central venous pressure by 59%, cardiomyocyte hypertrophy by 54%, and ventricular dilatation by 79% (P < 0.05). Therefore, blockade of the UT receptor reduced mortality and improved cardiac function in this model of myocardial infarction and CHF, suggesting an important role for UII in the pathogenesis of this condition.
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Regulación de la Expresión Génica/efectos de los fármacos , Insuficiencia Cardíaca/prevención & control , Infarto del Miocardio/prevención & control , Sulfonamidas/farmacología , Urotensinas/antagonistas & inhibidores , Animales , Biomarcadores/metabolismo , Presión Sanguínea , Tamaño de la Célula/efectos de los fármacos , Vasos Coronarios , Modelos Animales de Enfermedad , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/patología , Insuficiencia Cardíaca/fisiopatología , Humanos , Ligadura , Masculino , Infarto del Miocardio/sangre , Infarto del Miocardio/complicaciones , Infarto del Miocardio/patología , Infarto del Miocardio/fisiopatología , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Ratas , Ratas Endogámicas Lew , Urotensinas/sangre , Función Ventricular Izquierda/efectos de los fármacos , BencenosulfonamidasRESUMEN
Gene identification followed by determination of the expression of genes in a given disease and understanding of the function of the gene products is central to the drug discovery process. The ability to associate a specific gene with a disease can be attributed primarily to the extraordinary progress that has been made in the areas of gene sequencing and information technologies. Selection and validation of novel molecular targets have become of great importance in light of the abundance of new potential therapeutic drug targets that have emerged from human gene sequencing. In response to this revolution within the pharmaceutical industry, the development of high-throughput methods in both biology and chemistry has been necessitated. Further, the successful translation of basic scientific discoveries into clinical experimental medicine and novel therapeutics is an increasing challenge. As such, a new paradigm for drug discovery has emerged. This process involves the integration of clinical, genetic, genomic, and molecular phenotype data partnered with cheminformatics. Central to this process, the data generated are managed, collated, and interpreted with the use of informatics. This review addresses the use of new technologies that have arisen to deal with this new paradigm.
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Diseño de Fármacos , Genoma Humano , Biotecnología , Industria Farmacéutica , Genómica , Humanos , Farmacogenética , ProteómicaRESUMEN
Recent studies have postulated that the vasoactive peptide urotensin II (UII) plays a role in the control of vascular remodeling by inducing smooth muscle proliferation and fibroblast-mediated collagen deposition. The present study examined the expression of UII mRNA and immunoreactivity in rat carotid arteries before and after balloon angioplasty. In addition, the effect of UT receptor blockade was assessed in this model using a selective non-peptidic UT receptor antagonist, SB-611812. In carotid arteries of uninjured rats (naïve group), there was weak expression of UII in endothelial cells and little to no expression in vascular smooth muscle cells. At day 7, there was intimal proliferation associated with pronounced expression of UII in myointimal cells. By day 14, there was extensive intimal thickening exhibiting strong expression of UII. The contralateral arteries of all groups exhibited similar UII expression to that of naïve arteries. Animals treated with methylcellulose (vehicle) for 28 days showed a significant increase in intimal thickening compared to sham operated animals. Treatment with the SB-611812 resulted in a significant 60% reduction in intima-to-media area ratio when compared to vehicle treatment (P<0.005). These findings demonstrate upregulation of UII following balloon angioplasty, and a significant reduction in intimal lesion in response to UT receptor blockade. The present study suggests an important role for UII in the pathogenesis of restenosis following balloon angioplasty.
Asunto(s)
Angioplastia de Balón , Reestenosis Coronaria/metabolismo , Receptores Acoplados a Proteínas G/antagonistas & inhibidores , Receptores Acoplados a Proteínas G/metabolismo , Urotensinas/antagonistas & inhibidores , Urotensinas/metabolismo , Actinas/metabolismo , Animales , Arterias Carótidas/citología , Humanos , Unión Proteica , ARN Mensajero/genética , ARN Mensajero/metabolismo , RatasRESUMEN
The vasoactive peptide urotensin-II (U-II) is best known for its ability to regulate peripheral vascular and cardiac contractile function in vivo, and recent in vitro studies have suggested a role for the peptide in the control of vascular remodeling by inducing smooth muscle proliferation and fibroblast-mediated collagen deposition. Therefore, U-II may play a role in the etiology of atherosclerosis. In the present study we sought to determine the expression of U-II in coronary arteries from patients with coronary atherosclerosis and from normal control subjects, using immunohistochemistry and in situ hybridization. In normal coronary arteries, there was little expression of U-II in all types of cells. In contrast, in patients with coronary atherosclerosis, endothelial expression of U-II was significantly increased in all diseased segments (P<0.05). Greater expression of U-II was noted in endothelial cells of lesions with subendothelial inflammation or fibrofatty lesion compared with that of endothelial cells underlined by dense fibrosis or minimal intimal thickening. Myointimal cells and foam cells also expressed U-II. In most diseased segments, medial smooth muscle cells exhibited moderate expression of U-II. These findings demonstrate upregulation of U-II in endothelial, myointimal and medial smooth muscle cells of atherosclerotic human coronary arteries, and suggest a possible role for U-II in the pathogenesis of coronary atherosclerosis.
Asunto(s)
Enfermedad de la Arteria Coronaria/metabolismo , Vasos Coronarios/metabolismo , Células Espumosas/metabolismo , Regulación de la Expresión Génica , Túnica Íntima/metabolismo , Urotensinas/biosíntesis , Adulto , Enfermedad de la Arteria Coronaria/patología , Vasos Coronarios/patología , Femenino , Células Espumosas/patología , Humanos , Inmunohistoquímica , Hibridación in Situ , Masculino , Persona de Mediana Edad , Túnica Íntima/patologíaRESUMEN
1. SB-706375 potently inhibited [(125)I]hU-II binding to both mammalian recombinant and 'native' UT receptors (K(i) 4.7+/-1.5 to 20.7+/-3.6 nM at rodent, feline and primate recombinant UT receptors and K(i) 5.4+/-0.4 nM at the endogenous UT receptor in SJRH30 cells). 2. Prior exposure to SB-706375 (1 microM, 30 min) did not alter [(125)I]hU-II binding affinity or density in recombinant cells (K(D) 3.1+/-0.4 vs 5.8+/-0.9 nM and B(max) 3.1+/-1.0 vs 2.8+/-0.8 pmol mg(-1)) consistent with a reversible mode of action. 3. The novel, nonpeptidic radioligand [(3)H]SB-657510, a close analogue of SB-706375, bound to the monkey UT receptor (K(D) 2.6+/-0.4 nM, B(max) 0.86+/-0.12 pmol mg(-1)) in a manner that was inhibited by both U-II isopeptides and SB-706375 (K(i) 4.6+/-1.4 to 17.6+/-5.4 nM) consistent with the sulphonamides and native U-II ligands sharing a common UT receptor binding domain. 4. SB-706375 was a potent, competitive hU-II antagonist across species with pK(b) 7.29-8.00 in HEK293-UT receptor cells (inhibition of [Ca(2+)](i)-mobilization) and pK(b) 7.47 in rat isolated aorta (inhibition of contraction). SB-706375 also reversed tone established in the rat aorta by prior exposure to hU-II (K(app) approximately 20 nM). 5. SB-706375 was a selective U-II antagonist with >/=100-fold selectivity for the human UT receptor compared to 86 distinct receptors, ion channels, enzymes, transporters and nuclear hormones (K(i)/IC(50)>1 microM). Accordingly, the contractile responses induced in isolated aortae by KCl, phenylephrine, angiotensin II and endothelin-1 were unaltered by SB-706375 (1 microM). 6. In summary, SB-706375 is a high-affinity, surmountable, reversible and selective nonpeptide UT receptor antagonist with cross-species activity that will assist in delineating the pathophysiological actions of U-II in mammals.
Asunto(s)
Pirrolidinas/farmacología , Receptores Acoplados a Proteínas G/antagonistas & inhibidores , Receptores Acoplados a Proteínas G/genética , Sulfonamidas/farmacología , Algoritmos , Animales , Aorta Torácica/efectos de los fármacos , Unión Competitiva/efectos de los fármacos , Gatos , Línea Celular Tumoral , Membrana Celular/metabolismo , Haplorrinos , Humanos , Técnicas In Vitro , Ratones , Contracción Muscular/efectos de los fármacos , Músculo Liso Vascular/efectos de los fármacos , Ensayo de Unión Radioligante , Ratas , Proteínas Recombinantes/metabolismo , Rabdomiosarcoma/metabolismo , Especificidad de la EspecieRESUMEN
The mechanism responsible for the enhanced myocardial susceptibility to ischemic insult in patients with type 2 diabetes is not clear. The present study examines the effect of rosiglitazone treatment on cardiac insulin sensitization and its association with cardioprotection from ischemia/reperfusion injury in an animal model of diabetes. Male Zucker diabetic fatty (ZDF) rats were treated with rosiglitazone (3 mg . kg(-1) . day(-1) orally) or vehicle for 8 days before undergoing 30 min of coronary artery ligation, followed by reperfusion for 4 h (apoptosis) or 24 h (infarction). Rosiglitazone reduced the blood levels of glucose, triglycerides, and free fatty acids; enhanced cardiac glucose oxidation; and increased Akt phosphorylation (Akt-pS473) 2.1-fold and Akt kinase activity 1.8-fold in the ischemic myocardium. The phosphorylation of two downstream targets of Akt, glycogen synthase kinase-3beta and FKHR (forkhead transcription factor), was also enhanced by 2- and 2.9-fold, respectively. In rosiglitazone-treated rats, the number of apoptotic cardiomyocytes and the myocardial infarct size were decreased by 58 and 46%, respectively, and the myocardial contractile dysfunction was improved. Blockade of the insulin-Akt signaling pathway by wortmannin in the 8-day rosiglitazone-treated ZDF rats resulted in a markedly diminished cardioprotective effect of rosiglitazone. In addition, 8-day rosiglitazone treatment in Zucker lean rats or 2-day rosiglitazone treatment in ZDF rats, both of which showed no change in whole-body insulin sensitivity, resulted in a significant reduction in cardiac infarct size, but to a lesser degree when compared with that observed in 8-day rosiglitazone-treated ZDF rats. These results suggest that chronic treatment with rosiglitazone protects the heart against ischemia/reperfusion injury in ZDF rats, and that the enhanced cardiac protection observed after rosiglitazone treatment might be attributable in part to an improvement in cardiac insulin sensitivity.
Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Corazón/fisiopatología , Resistencia a la Insulina/fisiología , Infarto del Miocardio/prevención & control , Daño por Reperfusión Miocárdica/prevención & control , Tiazolidinedionas/uso terapéutico , Administración Oral , Animales , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Vasos Coronarios/fisiopatología , Ácidos Grasos no Esterificados/sangre , Corazón/efectos de los fármacos , Hipoglucemiantes/uso terapéutico , Masculino , Infarto del Miocardio/patología , Miocardio/metabolismo , Ratas , Ratas Zucker , Rosiglitazona , Triglicéridos/sangreRESUMEN
Urotensin II (U-II), a novel vasoactive peptide, possesses a wide range of cardiovascular effects. U-II binds a seven transmembrane spanning G-protein coupled receptor termed GPR14. In the present study, we have characterized U-II expression in both carotid and aortic atherosclerotic plaques. Using immunohistochemistry we demonstrated U-II immunoreactivity in endothelial, smooth muscle and inflammatory cells of both carotid and aortic plaques, with a clear propensity for intimal staining. Using quantitative real-time RT-PCR we observed both increased U-II and GPR14 mRNA expression in tissue extracts from abdominal aortic aneurysms. We also extended our PCR analysis to include leukocyte expression of U-II and GPR14. We found that lymphocytes were by far the largest producers of U-II mRNA. In contrast monocytes and macrophages were the largest producers of GPR14 mRNA, with relatively little expression in foam cells, lymphocytes, and platelets. Our findings qualitatively and quantitatively demonstrate increased expression of U-II in atherosclerosis with a large degree of inflammatory cell involvement. These findings suggest a possible role for U-II in the pathophysiology of atherosclerosis.
Asunto(s)
Aorta/metabolismo , Aneurisma de la Aorta Abdominal/metabolismo , Enfermedades de las Arterias Carótidas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Urotensinas/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Aneurisma de la Aorta Abdominal/fisiopatología , Aneurisma de la Aorta Abdominal/cirugía , Enfermedades de las Arterias Carótidas/fisiopatología , Enfermedades de las Arterias Carótidas/cirugía , Endarterectomía Carotidea , Expresión Génica , Humanos , Inmunohistoquímica , Leucocitos/fisiología , Masculino , Persona de Mediana Edad , ARN Mensajero/metabolismo , Receptores Acoplados a Proteínas G/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Urotensinas/genéticaRESUMEN
Chronic heart failure (HF) has become a significant healthcare problem in the US. The number of new cases per year continues to grow steadily due to an ageing population and improved survival from acute coronary syndromes. As a consequence, the management of HF patients is of great importance. Effective management of HF includes stabilising the patient and improving the clinical symptoms associated with HF. Patients with HF have increased sympathetic nervous system activity that contributes to impaired cardiovascular function over time and subsequently results in death. beta-blockers prevent such impairment through inhibition of the sympathetic nervous system neurohormonal pathway. Numerous clinical trials conducted over the past decade have demonstrated that beta-blockers, in conjunction with angiotensin-converting enzyme inhibitors, are not only effective but are superior to other medical interventions for the treatment of HF. The standard of care for patients with HF now includes beta-blockers as well as ACE inhibitors.