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1.
BMC Public Health ; 17(1): 452, 2017 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-28511688

RESUMEN

BACKGROUND: Poor adherence to micronutrient supplementation often limits the effectiveness of public health programs. While predictors of adherence to micronutrient supplementation during pregnancy are well documented, information on adherence to preconception supplements is scarce. The objective of this study was to describe the predictors of adherence to preconception and prenatal micronutrient supplementation among women participating in a randomized control trial in Vietnam. METHODS: Adherence data were collected prospectively from a double blind randomized controlled trial in rural Vietnam. Five thousand eleven women of reproductive age were randomized to receive preconception supplements for weekly consumption containing either: Folic Acid, Iron and Folic Acid (IFA), or Multiple Micronutrients. Women who became pregnant received prenatal IFA supplements for daily consumption through delivery. Village health workers visited participants' homes every two weeks to deliver supplements and record consumption and side effects. Multivariate logistic regression was used to assess individual, household, and programmatic predictors of supplement adherence. RESULTS: Adherence was high with 78 and 82% of the women consuming more than 80% of the preconception and prenatal supplements, respectively. Women of minority ethnicity (OR = 0.78 95% CI = 0.67, 0.91) and farmers (OR = 0.71 95% CI = 0.58, 0.88) were less likely to consume >80% of the preconception supplements while socioeconomic status (SES) (OR = 2.71 highest vs. lowest quintile; 95% CI = 2.10, 3.52) was positively associated with >80% adherence in the entire preconception sample with available information (n = 4417). Women in their first pregnancy had lower prenatal adherence compared to multiparous women. At the programmatic level, each village health worker visit was associated with higher odds of >80% adherence by 3-5% before pregnancy and 18% during pregnancy. CONCLUSIONS: Key determinants of adherence included SES, ethnicity, occupation (farmer) and parity which may be helpful for targeting women for counseling on supplement adherence. Increased contact with village health workers was positively associated with adherence to micronutrient supplementation both before conception and during pregnancy indicating the need for resources to support community outreach to women of reproductive age. TRIAL REGISTRATION: NCT01665378 . Registered on August 12, 2012.


Asunto(s)
Suplementos Dietéticos/estadística & datos numéricos , Cumplimiento de la Medicación/estadística & datos numéricos , Micronutrientes/administración & dosificación , Adulto , Método Doble Ciego , Femenino , Ácido Fólico/administración & dosificación , Humanos , Hierro/administración & dosificación , Micronutrientes/uso terapéutico , Paridad , Embarazo , Estudios Prospectivos , Población Rural , Factores Socioeconómicos , Vietnam
2.
Public Health Nutr ; 19(5): 861-71, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26139153

RESUMEN

OBJECTIVE: In India, national databases indicate anaemia prevalence of 80 % among 6-35-month-old children and 58 % among 36-59-month-old children. The present study aimed to characterise anaemia and the associated factors among infants and pre-schoolers living in rural India. DESIGN: Multivariate logistic regression analysis of data collected prior to an intervention trial. Fe-deficiency with anaemia (IDA), Fe deficiency with no anaemia (IDNA) and anaemia without Fe deficiency were defined. Serum ferritin, soluble transferrin receptor (sTfR) and sTfR/log ferritin index were used to indicate Fe status. SETTING: Twenty-six villages of Nalgonda district, Telangana, India. Data were collected in community sites. Participants Four hundred and seventy-six infants (aged 6-12 months), 316 pre-schoolers (aged 29-56 months) and their mothers. RESULTS: Prevalence of anaemia among infants and pre-schoolers was 66·4 and 47·8 %, prevalence of IDA was 52·2 and 42·1 %, prevalence of IDNA was 22·2 and 29·8 %, prevalence of anaemia without Fe deficiency was 14·2 and 5·7 %. Among infants, anaemia was positively associated with maternal anaemia (OR=3·31; 95 % CI 2·10, 5·23; P<0·001), and sTfR/log ferritin index (OR=2·21; 95 % CI 1·39, 3·54; P=0·001). Among pre-schoolers, anaemia was positively associated with maternal anaemia (OR=3·77; 95 % CI 1·94, 7·30; P<0·001), sTfR/log ferritin index (OR=5·29; 95 % CI 2·67, 10·50; P<0·001), high C-reactive protein (OR=4·39; 95 % CI 1·91, 10·06, P<0·001) and young age (29-35 months: OR=1·92; 05 % CI 1·18, 3·13, P=0·009). CONCLUSIONS: Anaemia prevalence continues to be high among infants and pre-schoolers in rural India. Based on sTfR/ferritin index, Fe deficiency is a major factor associated with anaemia. Anaemia is also associated with inflammation among pre-schoolers and with maternal anaemia among infants and pre-schoolers, illustrating the importance of understanding the aetiology of anaemia in designing effective control strategies.


Asunto(s)
Anemia Ferropénica/diagnóstico , Anemia Ferropénica/epidemiología , Anemia/diagnóstico , Anemia/epidemiología , Deficiencias de Hierro , Población Rural , Anemia/sangre , Anemia Ferropénica/sangre , Índice de Masa Corporal , Peso Corporal , Proteína C-Reactiva/metabolismo , Preescolar , Composición Familiar , Femenino , Ferritinas/sangre , Ácido Fólico/sangre , Abastecimiento de Alimentos , Humanos , India , Lactante , Hierro/sangre , Modelos Logísticos , Masculino , Micronutrientes/administración & dosificación , Micronutrientes/sangre , Morbilidad , Análisis Multivariante , Evaluación Nutricional , Prevalencia , Receptores de Transferrina/sangre , Factores de Riesgo , Factores Socioeconómicos , Vitamina B 12/sangre
3.
Matern Child Nutr ; 11 Suppl 4: 203-13, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25819697

RESUMEN

Inadequate energy intake and poor diet quality are important causes of chronic child undernutrition. Strategies for improving diet quality using lipid-based nutrient supplements (LNS) are currently being tested in several countries. To date, information on children's dietary intakes during LNS use is available only from Africa. In this study, we collected 24-h dietary recalls at baseline, 3, 6, 9 and 12 months on Honduran children (n = 298) participating in a cluster-randomised trial of LNS. Generalised estimating equations were used to examine differences in number of servings of 12 food groups in the LNS and control arms, and multi-level mixed effects models were used to compare macro- and micronutrient intakes. Models accounted for clustering and adjusted for child's age, season and breastfeeding status. Mean daily servings of 12 food groups did not differ by study arm at baseline and remained similar throughout the study with the exception of groups that were partially or entirely supplied by LNS (nuts and nut butters, fats, and sweets). Baseline intakes of energy, fat, carbohydrates, protein, folate and vitamin A, but not vitamin B12, iron and zinc were lower in the LNS than control arm. The change in all macro- and micronutrients from baseline to each study visit was larger for the LNS arm than the control, except for carbohydrates from baseline to 9 months. These findings indicate that LNS improved the macro- and micronutrient intakes of young non-malnourished Honduran children without replacing other foods in their diet.


Asunto(s)
Grasas de la Dieta/administración & dosificación , Suplementos Dietéticos , Ingestión de Energía , Desnutrición/dietoterapia , Micronutrientes/administración & dosificación , Lactancia Materna , Preescolar , Análisis por Conglomerados , Carbohidratos de la Dieta/administración & dosificación , Carbohidratos de la Dieta/análisis , Grasas de la Dieta/análisis , Proteínas en la Dieta/administración & dosificación , Proteínas en la Dieta/análisis , Ácido Fólico/administración & dosificación , Ácido Fólico/análisis , Estudios de Seguimiento , Calidad de los Alimentos , Honduras , Humanos , Lactante , Fórmulas Infantiles/química , Fenómenos Fisiológicos Nutricionales del Lactante , Hierro de la Dieta/administración & dosificación , Hierro de la Dieta/análisis , Recuerdo Mental , Micronutrientes/análisis , Vitamina A/administración & dosificación , Vitamina A/análisis , Vitamina B 12/administración & dosificación , Vitamina B 12/análisis , Zinc/administración & dosificación , Zinc/análisis
4.
ACS Med Chem Lett ; 15(4): 478-485, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38628803

RESUMEN

A novel class of nonpeptide melanocortin type 2 receptor (MC2R) antagonists was discovered through modification of known nonpeptide MC4R ligands. Structure-activity relationship (SAR) studies led to the discovery of 17h (CRN04894), a highly potent and subtype-selective first-in-class MC2R antagonist, which demonstrated remarkable efficacy in a rat model of adrenocorticotrophic hormone (ACTH)-stimulated corticosterone secretion. Oral administration of 17h suppressed ACTH-stimulated corticosterone secretion in a dose-dependent manner at doses ≥3 mg/kg. With its satisfactory pharmaceutical properties, 17h was advanced to Phase 1 human clinical trials in healthy volunteers with the goal of moving into patient trials to evaluate CRN04894 for the treatment of ACTH-dependent diseases, including congenital adrenal hyperplasia (CAH) and Cushing's disease (CD).

5.
Nutrients ; 14(7)2022 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-35405979

RESUMEN

Background: About 47% of children < 5 years of age are stunted in Guatemala. In this study, the investigators aimed to compare growth and cognitive outcomes between children in second grade that attended five Guatemala City Municipal Nurseries (GCMN) vs. same sex, grade, and age-matched children. Methods: A cross-sectional design nested in a retrospective cohort was implemented between 2015 and 2019. Children that attended the GCMN and matched controls completed a math test and validated receptive language and fluid intelligence tests. The primary caregivers completed a sociodemographic survey. General and generalized linear mixed effect models were used to compare children that attended the GCMN vs. controls. The models were adjusted by maternal education, sex, asset score, and other relevant covariates. Results: Children that attended the GCMN exhibited greater math and fluid intelligence scores relative to the controls in the adjusted models (ß = 6.48; 95% CI (2.35−10.61)) and (ß = 1.20; 95% CI (0.12−2.29)), respectively. Lower odds of stunting were significant for children who went to any early childcare institution (AOR = 0.28; 95% CI (0.09−0.89)). Conclusions: The importance of integrating nutrition and high-quality early childhood education interventions in cognitive and growth outcomes is highlighted in this study. The GCMN model may be a scalable model in similar low-resource settings.


Asunto(s)
Casas Cuna , Niño , Preescolar , Estudios Transversales , Trastornos del Crecimiento , Guatemala/epidemiología , Humanos , Lactante , Inteligencia , Estudios Retrospectivos
6.
Endocrinology ; 148(2): 857-67, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17095587

RESUMEN

Suppression of the hypothalamic-pituitary-gonadal axis by peptides that act at the GnRH receptor has found widespread use in clinical practice for the management of sex-steroid-dependent diseases (such as prostate cancer and endometriosis) and reproductive disorders. Efforts to develop orally available GnRH receptor antagonists have led to the discovery of a novel, potent nonpeptide antagonist, NBI-42902, that suppresses serum LH concentrations in postmenopausal women after oral administration. Here we report the in vitro and in vivo pharmacological characterization of this compound. NBI-42902 is a potent inhibitor of peptide radioligand binding to the human GnRH receptor (K(i) = 0.56 nm). Tritiated NBI-42902 binds with high affinity (K(d) = 0.19 nm) to a single class of binding sites and can be displaced by a range of peptide and nonpeptide GnRH receptor ligands. In vitro experiments demonstrate that NBI-42902 is a potent functional, competitive antagonist of GnRH stimulated IP accumulation, Ca(2+) flux, and ERK1/2 activation. It did not stimulate histamine release from rat peritoneal mast cells. Finally, it is effective in lowering serum LH in castrated male macaques after oral administration. Overall, these data provide a benchmark of pharmacological characteristics required for a nonpeptide GnRH antagonist to effectively suppress gonadotropins in humans and suggest that NBI-42902 may have clinical utility as an oral agent for suppression of the hypothalamic-pituitary-gonadal axis.


Asunto(s)
Receptores LHRH/antagonistas & inhibidores , Timina/análogos & derivados , Administración Oral , Animales , Sitios de Unión , Unión Competitiva , Bloqueadores de los Canales de Calcio/farmacología , Línea Celular , Activación Enzimática/efectos de los fármacos , Hormona Liberadora de Gonadotropina/farmacología , Liberación de Histamina/efectos de los fármacos , Humanos , Fosfatos de Inositol/antagonistas & inhibidores , Fosfatos de Inositol/metabolismo , Ligandos , Hormona Luteinizante/sangre , Macaca , Masculino , Mastocitos/metabolismo , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Orquiectomía , Receptores LHRH/metabolismo , Timina/administración & dosificación , Timina/metabolismo , Timina/farmacología
7.
J Med Chem ; 49(2): 637-47, 2006 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-16420049

RESUMEN

Peptide agonists and antagonists of the human gonadotropin-releasing hormone receptor (GnRH-R) are widely used to treat a range of reproductive hormone related diseases. Recently, nonpeptide, orally available GnRH-R antagonists have emerged from several chemical classes. To understand how a relatively large peptide-binding pocket can recognize numerous nonpeptide ligands, we undertook a systematic mapping of GnRH-R residues involved in the binding of three nonpeptide antagonists. A region composed of the extracellular portions of transmembrane helices 6 and 7, extracellular loop 3, and the N-terminal domain significantly contributed to nonpeptide antagonist binding. However, each molecule was affected by a different subset of residues in these regions, indicating that each appears to occupy distinct, partially overlapping subregions within the more extensive peptide-binding pocket. Moreover, the resulting receptor interaction maps provide a basis to begin to reconcile structure-activity relationships between various nonpeptide and peptide series and facilitate the design of improved therapeutic agents.


Asunto(s)
Indoles/farmacología , Modelos Moleculares , Compuestos de Fenilurea/farmacología , Pirimidinonas/farmacología , Receptores LHRH/antagonistas & inhibidores , Timina/análogos & derivados , Secuencia de Aminoácidos , Animales , Sitios de Unión , Células COS , Chlorocebus aethiops , Humanos , Indoles/química , Ligandos , Datos de Secuencia Molecular , Mutación , Péptidos/química , Compuestos de Fenilurea/química , Mutación Puntual , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Pirimidinonas/química , Ensayo de Unión Radioligante , Receptores LHRH/agonistas , Receptores LHRH/genética , Homología de Secuencia de Aminoácido , Relación Estructura-Actividad , Timina/química , Timina/farmacología
8.
J Med Chem ; 49(21): 6170-6, 2006 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-17034124

RESUMEN

We have investigated the specific interactions of a series thienopyrimidinediones with the gonadotropin-releasing hormone receptor (GnRH-R). Competitive radioligand binding assays were used to determine the effect of several mutants on nonpeptide binding. Distinct interactions were observed in two separate regions: the N-terminal end of TM7 and the C-terminal end of TM6. The effects of mutants at D302((7.32)) and H306((7.36)) suggest that these residues are part of a hydrogen-bond network important for anchoring the nonpeptides. Structure-activity relationships indicated urea substituents on the 6-(4-aminophenyl) group with a trans conformational preference bind with high affinity and are sensitive to D302((7.32)) mutations. Another interaction area was found between the N-benzyl-N-methylamino substituent and L300((6.68)) and Y290((6.58)). These interaction sites facilitated the derivation of a model in which a representative member of the series was docked into GnRH-R. The model is consistent with known SAR and illuminates inconsistencies with previous hypotheses regarding how this series interacts with the receptor.


Asunto(s)
Modelos Moleculares , Pirimidinas/síntesis química , Receptores LHRH/antagonistas & inhibidores , Receptores LHRH/química , Tiofenos/síntesis química , Secuencia de Aminoácidos , Animales , Unión Competitiva , Células COS , Chlorocebus aethiops , Humanos , Ligandos , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Estructura Secundaria de Proteína , Pirimidinas/química , Pirimidinas/farmacología , Ensayo de Unión Radioligante , Receptores LHRH/genética , Homología de Secuencia de Aminoácido , Relación Estructura-Actividad , Tiofenos/química , Tiofenos/farmacología
9.
J Med Chem ; 48(4): 1169-78, 2005 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-15715483

RESUMEN

Further structure-activity relationship studies of a series of substituted uracils at the 1, 3, and 5 positions resulted in the discovery of several potent antagonists of the human gonadotropin-releasing hormone receptor. Uracils bearing a side chain derived from phenylglycinol at the 3-position were shown to be orally bioavailable in monkeys. 3-[(2R)-Amino-2-phenylethyl]-1-(2,6-difluorobenzyl)-5-(2-fluoro-3-methoxyphenyl)-6-methylpyrimidin-2,4-dione (R-13b, NBI 42902) displayed subnanomolar binding affinity (K(i) = 0.56 nM) and was a potent functional antagonist (IC(50) = 3.0 nM in Ca(2+) flux assay) at the human GnRH receptor. It also bound to the monkey GnRH receptor with high affinity (K(i) = 3.9 nM). In addition, R-13bhad good plasma exposure in cynomolgus monkeys after oral administration, with a C(max) of 737 ng/mL and an AUC of 2392 ng/mL.h at a 10 mg/kg dose. Moreover, oral administration of R-13b to castrated male cynomolgus monkeys resulted in a significant decrease in serum levels of luteinizing hormone. These results demonstrate that compounds from this series of uracils are potent GnRH antagonists with good oral bioavailability and efficacy in nonhuman primates.


Asunto(s)
Receptores LHRH/antagonistas & inhibidores , Timina/análogos & derivados , Timina/síntesis química , Administración Oral , Animales , Disponibilidad Biológica , Cristalografía por Rayos X , Diseño de Fármacos , Humanos , Técnicas In Vitro , Macaca fascicularis , Masculino , Membranas/efectos de los fármacos , Membranas/metabolismo , Estructura Molecular , Orquiectomía , Hipófisis/efectos de los fármacos , Hipófisis/metabolismo , Ratas , Especificidad de la Especie , Estereoisomerismo , Relación Estructura-Actividad , Timina/química , Timina/farmacología
10.
J Med Chem ; 46(9): 1769-72, 2003 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-12699396

RESUMEN

SAR studies of 7-phenylpyrrolo[1,2-a]pyrimid-4-ones 1 and 2, and 2-phenylimidazolo[1,2-a]pyrimidines 3 and 4, as nonpeptide human GnRH receptor antagonists, lead us to believe that the aromatic ring at position-2 of 4 is no longer crucial for the binding once an aryl group is incorporated at postion-6. We report here the use of a 2-alkyl group on the imidazolo[1,2-a]pyrimidone core to generate potent GnRH receptor antagonists. This discovery enabled us to obtain smaller but equally potent GnRH receptor antagonists.


Asunto(s)
Pirimidinonas/síntesis química , Receptores LHRH/antagonistas & inhibidores , Diseño de Fármacos , Humanos , Pirimidinonas/química , Pirimidinonas/farmacología , Relación Estructura-Actividad
11.
J Med Chem ; 46(11): 2023-6, 2003 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-12747774

RESUMEN

Based on SAR from bicyclic GnRH antagonists such as 6-aminomethyl-7-arylpyrrolo[1,2-a]pyrimid-4-ones (1) and 2-aryl-3-aminomethylimidazolo[1,2-a]pyrimid-5-ones (2a,b), a series of novel uracil compounds (4) were derived as the GnRH antagonists. Their syntheses and initial SAR are discussed herein. This is the first time that monocycle-based GnRH receptor antagonists are reported.


Asunto(s)
Imidazoles/síntesis química , Pirroles/síntesis química , Receptores LHRH/antagonistas & inhibidores , Uracilo/síntesis química , Animales , Estabilidad de Medicamentos , Humanos , Imidazoles/química , Imidazoles/farmacología , Técnicas In Vitro , Tasa de Depuración Metabólica , Ratones , Microsomas Hepáticos/metabolismo , Pirroles/química , Pirroles/farmacología , Estereoisomerismo , Relación Estructura-Actividad , Uracilo/química , Uracilo/farmacología
12.
J Med Chem ; 47(5): 1259-71, 2004 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-14971906

RESUMEN

Based on the SAR from bicyclic gonadotropin-releasing hormone (GnRH) antagonists such as 6-aminomethyl-7-aryl-pyrrolo[1,2-a]pyrimid-4-ones (5) and 2-aryl-3-aminomethyl-imidazolo[1,2-a]pyrimid-5-ones (6a,b), a series of novel uracil compounds (8) were derived as GnRH antagonists. The synthesis and SAR studies of 6-methyluracils as human GnRH receptor antagonists are discussed herein. Introduction of a small methyl substituent at the beta-position of the N3 side-chain improved the GnRH binding potency by 5-10-fold. Introduction of a methyl group of (R)-configuration at the alpha-carbon of the N-3 side-chain gave a modest improvement in binding affinity over the unsubstituted ethylene analogues. This modification enabled us to make uracil compounds without the labile 2-pyridylethyl motif on the basic nitrogen while still maintained excellent potency against the hGnRH receptor.


Asunto(s)
Receptores LHRH/antagonistas & inhibidores , Uracilo/análogos & derivados , Uracilo/síntesis química , Animales , Área Bajo la Curva , Disponibilidad Biológica , Calcio/antagonistas & inhibidores , Calcio/metabolismo , Línea Celular , Cristalografía por Rayos X , Haplorrinos , Humanos , Tasa de Depuración Metabólica , Ratones , Microsomas Hepáticos/metabolismo , Estructura Molecular , Ensayo de Unión Radioligante , Estereoisomerismo , Relación Estructura-Actividad , Uracilo/farmacocinética , Uracilo/farmacología
13.
J Med Chem ; 47(14): 3483-6, 2004 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-15214774

RESUMEN

Uracils possessing N-3 side chains derived from various amino alcohols were designed and synthesized as potent human gonadotropin releasing hormone receptor antagonists. The compounds herein presented displayed superior metabolic stability than their predecessor molecules. Selected compounds from this series featured good oral bioavailability in mice and cynomolgus monkeys.


Asunto(s)
Receptores de HL/antagonistas & inhibidores , Uracilo/análogos & derivados , Uracilo/síntesis química , Administración Oral , Animales , Disponibilidad Biológica , Humanos , Macaca fascicularis , Ratones , Estereoisomerismo , Relación Estructura-Actividad , Uracilo/farmacología
14.
Ann N Y Acad Sci ; 1308: 218-231, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24673168

RESUMEN

This article describes the development, design, and implementation of an integrated randomized double-masked placebo-controlled trial (Project Grow Smart) that examines how home/preschool fortification with multiple micronutrient powder (MNP) combined with an early child-development intervention affects child development, growth, and micronutrient status among infants and preschoolers in rural India. The 1-year trial has an infant phase (enrollment age: 6-12 months) and a preschool phase (enrollment age: 36-48 months). Infants are individually randomized into one of four groups: placebo, placebo plus early learning, MNP alone, and MNP plus early learning (integrated intervention), conducted through home visits. The preschool phase is a cluster-randomized trial conducted in Anganwadi centers (AWCs), government-run preschools sponsored by the Integrated Child Development System of India. AWCs are randomized into MNP or placebo, with the MNP or placebo mixed into the children's food. The evaluation examines whether the effects of the MNP intervention vary by the quality of the early learning opportunities and communication within the AWCs. Study outcomes include child development, growth, and micronutrient status. Lessons learned during the development, design, and implementation of the integrated trial can be used to guide large-scale policy and programs designed to promote the developmental, educational, and economic potential of children in developing countries.


Asunto(s)
Desarrollo Infantil , Fenómenos Fisiológicos Nutricionales Infantiles , Intervención Educativa Precoz , Intervención Médica Temprana , Preescolar , Conducta Cooperativa , Prestación Integrada de Atención de Salud/organización & administración , Método Doble Ciego , Femenino , Estado de Salud , Humanos , India , Lactante , Masculino , Micronutrientes/administración & dosificación , Relaciones Madre-Hijo , Grupo de Atención al Paciente , Proyectos Piloto , Población Rural , Recursos Humanos
15.
Science ; 335(6070): 851-5, 2012 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-22344443

RESUMEN

The lyso-phospholipid sphingosine 1-phosphate modulates lymphocyte trafficking, endothelial development and integrity, heart rate, and vascular tone and maturation by activating G protein-coupled sphingosine 1-phosphate receptors. Here, we present the crystal structure of the sphingosine 1-phosphate receptor 1 fused to T4-lysozyme (S1P(1)-T4L) in complex with an antagonist sphingolipid mimic. Extracellular access to the binding pocket is occluded by the amino terminus and extracellular loops of the receptor. Access is gained by ligands entering laterally between helices I and VII within the transmembrane region of the receptor. This structure, along with mutagenesis, agonist structure-activity relationship data, and modeling, provides a detailed view of the molecular recognition and requirement for hydrophobic volume that activates S1P(1), resulting in the modulation of immune and stromal cell responses.


Asunto(s)
Receptores de Lisoesfingolípidos/química , Anilidas/química , Sitios de Unión , Cristalografía por Rayos X , Modelos Moleculares , Muramidasa/química , Mutagénesis , Organofosfonatos/química , Conformación Proteica , Receptores de Lisoesfingolípidos/agonistas , Receptores de Lisoesfingolípidos/antagonistas & inhibidores , Receptores de Lisoesfingolípidos/genética , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética
16.
J Med Chem ; 51(23): 7478-85, 2008 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-19006286

RESUMEN

The discovery of novel uracil phenylethylamines bearing a butyric acid as potent human gonadotropin-releasing hormone receptor (hGnRH-R) antagonists is described. A major focus of this optimization was to improve the CYP3A4 inhibition liability of these uracils while maintaining their GnRH-R potency. R-4-{2-[5-(2-fluoro-3-methoxyphenyl)-3-(2-fluoro-6-[trifluoromethyl]benzyl)-4-methyl-2,6-dioxo-3,6-dihydro-2H-pyrimidin-1-yl]-1-phenylethylamino}butyric acid sodium salt, 10b (elagolix), was identified as a potent and selective hGnRH-R antagonist. Oral administration of 10b suppressed luteinizing hormone in castrated macaques. These efforts led to the identification of 10b as a clinical compound for the treatment of endometriosis.


Asunto(s)
Descubrimiento de Drogas , Hidrocarburos Fluorados/farmacología , Pirimidinas/farmacología , Receptores LHRH/antagonistas & inhibidores , Animales , Células CACO-2 , Inhibidores del Citocromo P-450 CYP3A , Evaluación Preclínica de Medicamentos , Humanos , Hidrocarburos Fluorados/química , Hidrocarburos Fluorados/metabolismo , Macaca fascicularis , Masculino , Microsomas Hepáticos/química , Microsomas Hepáticos/metabolismo , Estructura Molecular , Pirimidinas/química , Pirimidinas/metabolismo , Estereoisomerismo , Relación Estructura-Actividad , Factores de Tiempo
17.
J Biol Chem ; 279(22): 23214-22, 2004 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-15054093

RESUMEN

Many members of the chemokine receptor family of G protein-coupled receptors utilize multiple endogenous ligands. However, differences between the signaling properties of multiple chemokines through a single receptor have yet to be well characterized. In this study we investigated the early signaling events of CCR7 initiated by its two endogenous ligands, CCL19 and CCL21. Both CCL19 and CCL21 induce G protein activation and calcium mobilization with equal potency. However, only activation by CCL19, not CCL21, promotes robust desensitization of endogenous CCR7 in the human T cell lymphoma cell line H9. Desensitization occurs through the induction of receptor phosphorylation and beta-arrestin recruitment (shown in HEK293 cells expressing CCR7-FLAG). The sites of CCL19-induced phosphorylation were mapped by mutating to alanines the serines and threonines found within kinase phosphorylation consensus sequences in the carboxyl terminus of CCR7. A cluster of sites, including Thr-373-376 and Ser-378 is important for CCL19-mediated phosphorylation of the receptor, whereas residues serine 356, 357, 364, and 365 are important for basal receptor phosphorylation by protein kinase C. Activation of CCR7 by both ligands leads to signaling to the ERK1/2 mitogen-activated protein kinase pathway. However, CCL19 promotes 4-fold more ERK1/2 phosphorylation than does CCL21. The mechanism by which CCL19 activates ERK1/2 was determined to be beta-arrestin-dependent, because it is reduced both by depletion of beta-arrestin-2 with small interfering RNA and by elimination of the phosphorylation sites in the tail of the receptor. Taken together, these findings demonstrate that CCL19 and CCL21 place CCR7 in functionally distinct conformations that are independent of their G protein-coupling potency: one that allows the efficient desensitization of the receptor and activation of ERK1/2, and another that is impaired in these functions.


Asunto(s)
Arrestinas/metabolismo , Receptores de Quimiocina/metabolismo , Transducción de Señal , Línea Celular Tumoral , Quimiocina CCL19 , Quimiocina CCL21 , Quimiocinas CC/metabolismo , Humanos , Ligandos , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Mutación , Fosforilación , Conformación Proteica , Receptores CCR7 , Receptores de Quimiocina/agonistas , Receptores de Quimiocina/genética , Arrestina beta 2 , beta-Arrestinas
18.
J Biol Chem ; 279(33): 34115-22, 2004 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-15155770

RESUMEN

Efforts to develop orally available gonadotropin-releasing hormone (GnRH) receptor antagonists have led to the discovery of several classes of potent nonpeptide antagonists. Here we investigated molecular interactions of three classes of nonpeptide antagonists with human, rat, and macaque GnRH receptors. Although all are high affinity ligands of the human receptor (K(i) <5 nm), these compounds show reduced affinity for the macaque receptor and bind only weakly (K(i) >1 microm) to the rat receptor. To identify residues responsible for this selectivity, a series of chimeric receptors and mutant receptors was constructed and evaluated for nonpeptide binding. Surprisingly, 4 key residues located in the amino terminus (Met-24) and extracellular loops II (Ser-203, Gln-208) and III (Leu-300) of the GnRH receptor appear to be primarily responsible for species-selective binding. Comparisons of reciprocal mutations suggest that these may not be direct contacts but rather may be involved in organizing extracellular portions of the receptor. These data are novel because most previous reports of residues involved in binding of nonpeptide ligands to peptide-activated G protein-coupled receptors, including the GnRH receptor as well as mono-amine receptors, have identified binding sites in the transmembrane regions.


Asunto(s)
Receptores LHRH/química , Receptores LHRH/metabolismo , Animales , Sitios de Unión , Unión Competitiva , Células CHO , Bovinos , Quimera , Cricetinae , Relación Dosis-Respuesta a Droga , Humanos , Concentración de Iones de Hidrógeno , Cinética , Ligandos , Macaca mulatta , Modelos Químicos , Mutación , Fragmentos de Péptidos/farmacología , Péptidos/química , Mutación Puntual , Unión Proteica , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Ratas , Receptores LHRH/antagonistas & inhibidores , Rodopsina/química , Homología de Secuencia de Aminoácido , Especificidad de la Especie , Transfección
19.
Bioorg Med Chem Lett ; 13(19): 3311-5, 2003 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-12951116

RESUMEN

The novel synthesis and SAR studies of 6-methyluracils as human GnRH receptor antagonists are discussed. Introduction of a small methyl substituent at the beta-position from N3 of the uracil improved the GnRH binding potency by 5- to 10-fold. The best compound from the series had binding affinity of 5 nM (K(i)) to the human GnRH receptor.


Asunto(s)
Receptores LHRH/antagonistas & inhibidores , Uracilo/análogos & derivados , Uracilo/síntesis química , Uracilo/farmacología , Relación Dosis-Respuesta a Droga , Humanos , Unión Proteica/efectos de los fármacos , Unión Proteica/fisiología , Receptores LHRH/fisiología , Relación Estructura-Actividad
20.
Bioorg Med Chem Lett ; 13(19): 3317-22, 2003 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-12951117

RESUMEN

A new class of small molecule GnRH antagonists, the 1-arylmethyl-3-(1-methyl-2-amino)ethyl-5-aryl-6-methyluracils, was designed and a novel stereoselective synthesis for these compounds was developed. The stereochemical integrities of key intermediates (S)-6 and (R)-6 were confirmed by a combination of X-ray crystallography and chiral HPLC determinations. SAR studies were performed, which allowed the identification of derivatives (R)-9f, (R)-9h and (R)-12 as potent hGnRH antagonists (K(i)=20 nM).


Asunto(s)
Receptores LHRH/antagonistas & inhibidores , Uracilo/análogos & derivados , Uracilo/síntesis química , Uracilo/farmacología , Relación Dosis-Respuesta a Droga , Humanos , Unión Proteica/efectos de los fármacos , Unión Proteica/fisiología , Receptores LHRH/fisiología , Estereoisomerismo , Relación Estructura-Actividad
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