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1.
Adv Nutr ; 14(5): 948-958, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37270030

RESUMEN

Achieving optimal health is an aspirational goal for the population, yet the definition of health remains unclear. The role of nutrition in health has evolved beyond correcting malnutrition and specific deficiencies and has begun to focus more on achieving and maintaining 'optimal' health through nutrition. As such, the Council for Responsible Nutrition held its October 2022 Science in Session conference to advance this concept. Here, we summarize and discuss the findings of their Optimizing Health through Nutrition - Opportunities and Challenges workshop, including several gaps that need to be addressed to advance progress in the field. Defining and evaluating various indices of optimal health will require overcoming these key gaps. For example, there is a strong need to develop better biomarkers of nutrient status, including more accurate markers of food intake, as well as biomarkers of optimal health that account for maintaining resilience-the ability to recover from or respond to stressors without loss to physical and cognitive performance. In addition, there is a need to identify factors that drive individualized responses to nutrition, including genotype, metabotypes, and the gut microbiome, and to realize the opportunity of precision nutrition for optimal health. This review outlines hallmarks of resilience, provides current examples of nutritional factors to optimize cognitive and performance resilience, and gives an overview of various genetic, metabolic, and microbiome determinants of individualized responses.


Asunto(s)
Microbioma Gastrointestinal , Ciencias de la Nutrición , Humanos , Estado Nutricional , Biomarcadores
2.
Stress Health ; 39(S1): 4-9, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37182211

RESUMEN

The National Institutes of Health (NIH) have recently gathered internal and external input towards a shared understanding of resilience in the wide context of human health and the biomedical sciences that would help accelerate advances in human health and its maintenance. This shared view is that resilience refers in general to a system's capacity to recover, grow, adapt, or resist perturbation from a challenge or stressor. Over time, a system's response to a challenge might show varied degrees of reactions that likely fluctuate in response to the type of challenge (internal and/or external), severity of the challenge, the length of time exposed to the challenge, other external factors and/or biological factors (innate and/or external). We have embarked on this special issue as an opportunity to explore commonalities amongst viewpoints on the science of resilience covered by the various NIH Institutes, Centers, and Offices (ICOs) with respect to the characterization of various systems, stressors, outcomes measures and metrics, and interventions and/or protective factors that are shared within each domain and across multiple domains. Here, resilience is characterized broadly by four areas of scientific study: molecular/cellular, physiologic, psychosocial and spiritual, and environmental/community resilience. Each area or domain provides general frameworks for designing studies that may help advance the science of resilience within the context of health maintenance. This special issue will also acknowledge the remaining gaps that impede advancement of the science of resilience and offer considerations for potential next steps towards addressing the research gaps.


Asunto(s)
Adaptación Fisiológica , National Institutes of Health (U.S.) , Humanos , Estados Unidos
3.
Stress Health ; 39(S1): 62-66, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37184110

RESUMEN

The National Institutes of Health have recently gathered internal and external input towards a shared understanding of resilience in the wide context of human health and the biomedical sciences that would help accelerate advances in human health and its maintenance. We suggest the current view that resilience refers in general to a system's capacity to recover, grow, adapt, or resist perturbation from a challenge or stressor. To help harmonize the design and reporting of resilience research studies across multiple domains we have developed and are proposing a Resilience Research Design (ResD) Tool. Researchers can use the Resilience ResD Tool to proceed through a flowchart of six questions that will guide identification of key features in a resilience research study. Through this special supplement, we have shown the application of the Resilience ResD Tool and suggest opportunities and gaps with respect to next steps towards operationalizing resilience research.


Asunto(s)
Salud , Resiliencia Psicológica , Estrés Psicológico , Humanos , Investigación Biomédica , Promoción de la Salud , Investigación Operativa , National Institutes of Health (U.S.) , Estados Unidos
5.
Nutrients ; 14(21)2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36364865

RESUMEN

Immune health products represent approximately 10% of all US dietary supplement sales. Claims made on products to support or boost the immune system are attractive to the otherwise healthy consumer who may or may not be experiencing certain life stressors. The purpose of this systematic review is to critically evaluate the purported benefits and/or potential harms of select dietary supplement ingredients frequently listed on the labels of products having immune health or related market claims. With a focus on resilience, research questions were related to whether dietary supplement ingredients are efficacious in preserving and protecting immune health in healthy individuals; and when faced with a stressor, whether taking a supplement prophylactically can assist in maintaining health and resisting or bouncing back more quickly. Thirty-nine randomized controlled studies involving populations including children, adults and seniors exposed to stressors, such as air travel, intense exercise, academic stress, and/or exposure to winter weather, met eligibility criteria. The studies included eight of the 27 supplement ingredients identified through a market-driven scoping review. Those ingredients used in single ingredient products were echinacea, elderberry, garlic, vitamin A, vitamin C, vitamin D, vitamin E, and zinc. Whereas some studies may point to evidence for benefit, specific gaps preclude the authors from making firm statements with regard to the overall evidence-base for these products and ingredients and in answering the research questions. As we move toward a vision of health promotion and resilience rather than a sole focus on disease prevention and treatment, further work in this area of dietary supplements is of utmost importance.


Asunto(s)
Productos Biológicos , Suplementos Dietéticos , Adulto , Niño , Humanos , Vitaminas , Ejercicio Físico , Sistema Inmunológico
6.
Life Sci ; 288: 120160, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34801514

RESUMEN

AIMS: This study aimed to: 1) investigate sex differences in heat-induced mitochondrial dysfunction, ROS production, and skeletal muscle injury in mice; 2) evaluate whether curcumin and astaxanthin, alone or together, would prevent those heat-induced changes. MAIN METHODS: Male and female C57BL/6J mice were treated with curcumin and astaxanthin for 10 days, then exposed to 39.5 °C heat for up to 3 h. Heat-induced hyperthermia, changes in mitochondrial morphology and function, and oxidative damage to skeletal muscle were evaluated. KEY FINDINGS: Although female mice had a slightly higher basal core body temperature (Tc) than male mice, peak Tc during heat exposure was significantly lower in females than in males. Heat increased ROS levels in skeletal muscle in both sexes; interestingly, the increases in ROS were greater in females than in males. Despite the above-mentioned differences, heat induced similar levels of mitochondrial fragmentation and membrane potential depolarization, caspase 3/7 activation, and injury in male and female skeletal muscle. Individual treatment of curcumin or astaxanthin did not affect basal and peak Tc but prevented heat-induced mitochondrial dysfunction, ROS increases, and apoptosis in a dose-dependent manner. Moreover, a low-dose combination of curcumin and astaxanthin, which individually showed no effect, reduced the heat-induced oxidative damage to skeletal muscle. SIGNIFICANCE: Both male and female mice can develop mitochondrial dysfunction and oxidative stress in skeletal muscle when exposed to heat stress. High doses of either curcumin or astaxanthin limit heat-induced skeletal muscle injury, but a low-dose combination of these ingredients may increase their efficacy.


Asunto(s)
Curcumina/farmacología , Respuesta al Choque Térmico , Hipertermia Inducida/efectos adversos , Músculo Esquelético/efectos de los fármacos , Enfermedades Musculares/tratamiento farmacológico , Especies Reactivas de Oxígeno/metabolismo , Animales , Antiinflamatorios no Esteroideos/farmacología , Dieta , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Músculo Esquelético/lesiones , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Enfermedades Musculares/etiología , Enfermedades Musculares/metabolismo , Enfermedades Musculares/patología , Estrés Oxidativo , Sustancias Protectoras/farmacología , Xantófilas/farmacología
7.
Nutr Res ; 96: 9-19, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34890857

RESUMEN

In the market of dietary supplements, a low level of certainty exists in the state of the science, coupled with not always knowing what is in the product. Together these issues make weighing benefits/risks difficult and hinder the ability to guide evidence-based practice decisions. The authors sought to identify priorities and develop potential solutions to address research gaps so that information disseminated, can ultimately, be relied upon, when trying to make appropriate and safe decisions. Using a modified-Delphi process, 8 panelists reviewed evidence, provided from systematic review, on dietary supplement ingredients for brain health, and prioritized gaps identified and offered potential solutions. Research gaps specific to dietary supplements research included the need for quality testing of products, the question of bioavailability and absorption of ingredients, and optimal composition and standardization of supplements under investigation. Other gaps related to populations studied; a general sense of bias towards focusing research on diseased rather than maintaining or optimizing performance in healthy populations. Additionally, the lack of uniform cognitive performance measures and metrics used across research is a gap, as well as whether the metrics are accurate representations of or even generalizable to "real-life" participants wishing to optimize their performance. Methodological quality and ethical concerns in the conduct and reporting of science encompass all issues. If resources map to potential solutions outlined in this paper, then these proposed next steps offered will help facilitate meaningful research, move evidence into practice recommendations, and ultimately develop better decision-making tools for consumers to trust and rely upon for making safe supplement decisions.


Asunto(s)
Encéfalo , Suplementos Dietéticos , Cognición , Humanos
8.
J Womens Health (Larchmt) ; 30(2): 207-211, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33164624

RESUMEN

Women tend to supplement their diets with multivitamin/mineral (MVM) supplements more often than men, and reports indicate that more than 90% of pregnant women in the United States supplement their diets with prenatal MVMs. Given the widespread use of MVMs among women and given the increasing efforts to unveil the importance of phenotype-specific health determinants, it seems imperative to review what is known about variations in nutrient physiology among women from different ethnic and racial groups and at different reproductive stages of life. In this study, we embark on an assessment of the scientific evidence and knowledge gaps that impact the precise determination of nutrient levels (specifically calcium, iron, and folic acid) that confer benefits to various subpopulations of women in the United States.


Asunto(s)
Ácido Fólico , Hierro , Calcio , Suplementos Dietéticos , Femenino , Humanos , Masculino , Embarazo , Atención Prenatal , Estados Unidos , Vitaminas
9.
J Nutr ; 149(6): 890-893, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-31149713

RESUMEN

In the US, 70% of pregnant women use an iron-containing prenatal supplement product; however, only 2.6% of pregnant women have iron-deficiency anemia and 16.3% are iron deficient. Yet, published data on the amounts and chemical forms of iron used in formulating these products are not available, although they are known to affect bioavailability. This information is especially important in comparing commercially available products with those that were tested in clinical trials. Our examination of nonprescription and prescription iron-containing prenatal supplement products in NIH's Dietary Supplement Label Database (DSLD) and DailyMed found the labeled amount of elemental iron ranged between 9 and 60 mg/serving in 148 nonprescription supplements and between 4.5 and 106 mg/serving in 101 prescription supplements. Ferrous fumarate was the preferred chemical form used in these products. In contrast, ferrous sulfate was the preferred chemical form of iron reported in the clinical trials summarized in a 2015 Cochrane Systematic review assessing the effects of daily oral iron supplements for pregnant women. Ferrous sulfate was not found on any prenatal supplement product label in the DSLD or DailyMed. The chemical forms of products on the market and those tested in clinical trials are dissimilar, and we believe this may have clinical implications. The findings raise several questions. Do outcomes in clinical trials correlate with the benefits and risks that might adhere to iron supplements with different iron formulations? Should the differences in chemical forms, their bioavailability, and safety profiles, be considered in greater depth when evaluating the effect of the various formulations on maternal iron nutriture? Should new clinical trials for pregnant and lactating women in the US use a form of iron not found in prenatal supplements sold in the US or should a more common form be used?


Asunto(s)
Suplementos Dietéticos/análisis , Hierro/química , Disponibilidad Biológica , Ensayos Clínicos como Asunto , Femenino , Compuestos Ferrosos/administración & dosificación , Humanos , Hierro/farmacocinética , Hierro de la Dieta/administración & dosificación , Hierro de la Dieta/farmacocinética , Embarazo , Atención Prenatal , Fenómenos Fisiologicos de la Nutrición Prenatal , Seguridad
10.
BMC Proc ; 12(Suppl 6): 6, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30044889

RESUMEN

The Office of Dietary Supplements, the National Institute on Minority Health and Health Disparities, the National Institute on Aging, and the National Institute of Diabetes and Digestive and Kidney Diseases, all components of the U.S. National Institutes of Health, co-sponsored an expert panel meeting to discuss the vitamin D paradox in Black Americans. The paradox is that despite markedly low (or "deficient") measures of vitamin D status in Black Americans, the incidence of falls, fractures, or osteopenia are significantly lower compared to White American counterparts with similar vitamin D status. Six panelists were invited to engage in guided discussions on the state of the science with respect to key knowledge gaps impacting vitamin D status and bone health. They were also asked to reflect on best approaches for advancing the science. A central theme throughout the discussions was that there may be many factors that impact Vitamin D levels in Black Americans and understanding these factors may be key to understanding mechanisms for improving bone health in all populations. Data presented showed that although adiposity, skin pigmentation, vitamin D binding protein polymorphisms, and genetics all contributed to differences in 25(OH)D levels in Black vs. White Americans, no one factor alone could fully explain the vitamin D paradox in Black Americans. However, the panelists did agree that the paradox is significant and warrants further investigation. There was consensus that Black Americans gained no skeletal benefits from high doses of vitamin D supplementation, and that high levels of the biomarker of vitamin D status, serum 25-hydroxyvitamin D or 25(OH)D, in this population are almost certain to result in adverse effects. Some panelists proposed that additional studies are needed so that the Institute of Medicine (IOM) can better define the safe upper limits of vitamin D intake in this and other subpopulations. Others suggested a need for better, more generalizable biomarkers of bone health to advance the science.

12.
J Acad Nutr Diet ; 117(9): 1429-1436, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28571654

RESUMEN

BACKGROUND: Prenatal supplements are often recommended to pregnant women to help meet their nutrient needs. Many products are available, making it difficult to choose a suitable supplement because little is known about their labeling and contents to evaluate their appropriateness. OBJECTIVE: To determine differences between prescription and nonprescription prenatal supplements available in the United States regarding declared nutrient and nonnutrient ingredients and the presence of dosing and safety-related information. DESIGN: Using two publicly available databases with information about prenatal supplement products, information from prescription and nonprescription product labels were extracted and evaluated. For the 82 prescription and 132 nonprescription products, declared label amounts of seven vitamins and minerals, docosahexaenoic acid (DHA), the presence of other nonnutrient components, and the presence of key safety and informational elements as identified in two Department of Health and Human Services Office of Inspector General (OIG)'s 2003 reports were compiled and compared. RESULTS: Compared with nonprescription products, prescription products contained significantly fewer vitamins (9±0.2 vs 11±0.3; P≤0.05) and minerals (4±0.1 vs 8±0.3; P≤0.05). Declared amounts of folic acid were higher in prescription products, whereas vitamin A, vitamin D, iodine, and calcium were higher in the nonprescription products. Amounts of iron, zinc, and DHA were similar. Virtually all products contained levels of one or more nutrients that exceeded the Recommended Dietary Allowances for pregnant and/or lactating women. Product type also influenced ingredients added. Fewer prescription products contained botanical ingredients (6% prescription vs 33% nonprescription) and probiotics (2% prescription vs 8% nonprescription). Only prescription products contained the stool softener docusate sodium. CONCLUSIONS: Our analysis of prenatal supplements indicates that prescription and nonprescription supplements differ in terms of declared composition and nutrient strength, but have labels that are similarly sparse regarding aspects of use such as dosing information.


Asunto(s)
Suplementos Dietéticos/normas , Etiquetado de Medicamentos/normas , Etiquetado de Alimentos/normas , Medicamentos sin Prescripción/normas , Medicamentos bajo Prescripción/normas , Bases de Datos Factuales , Etiquetado de Medicamentos/métodos , Femenino , Etiquetado de Alimentos/métodos , Humanos , Valor Nutritivo , Embarazo , Atención Prenatal , Fenómenos Fisiologicos de la Nutrición Prenatal , Ingesta Diaria Recomendada , Estados Unidos
13.
Neurochem Res ; 40(10): 2131-42, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26508288

RESUMEN

Nicotinic acetylcholine receptors (nAChRs) play a crucial role in a number of clinically relevant mental and neurological pathways, as well as autonomic and immune functions. The development of subtype-selective ligands for nAChRs therefore is potentially useful for targeted therapeutic management of conditions where nAChRs are involved. We tested if selectivity for a particular nAChR subtype can be achieved through small structural modifications of a lead compound containing the nicotinic pharmacophore by changing the distance between the electronegative elements. For this purpose, analogs of A-84543 were designed, synthesized and characterized as potentially new nAChR subtype-selective ligands. Compounds were tested for their binding properties in rat cerebral cortical tissue homogenates, and subtype-selectivity was determined using stably transfected HEK cells expressing different nAChR subtypes. All compounds synthesized were found to competitively displace [(3)H]-epibatidine ([(3)H]EB) from the nAChR binding site. Of all the analogues, H-11MNH showed highest affinity for nAChRs compared to a ~ fivefold to tenfold lower affinity of A-84543. All other compounds had affinities >10,000 nM. Both A-84543 and H-11MNH have highest affinity for α2ß2 and α4ß2 nAChRs and show moderate affinity for ß4- and α7-containing receptors. H-11MNH was found to be a full agonist with high potency at α3ß4, while A-84543 is a partial agonist with low potency. Based on their unique pharmacological binding properties we suggest that A-84543 and its desmethylpyrrolidine analog can be useful as pharmacological ligands for studying nAChRs if selective pharmacological and/or genetic tools are used to mask the function of other receptors subtypes.


Asunto(s)
Neuronas/efectos de los fármacos , Nicotina/farmacología , Nitrógeno/metabolismo , Piridinas/farmacología , Pirrolidinas/farmacología , Receptores Nicotínicos/metabolismo , Animales , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Humanos , Neuronas/metabolismo , Piridinas/metabolismo , Ratas , Receptores Nicotínicos/efectos de los fármacos , Relación Estructura-Actividad
14.
Phytochemistry ; 95: 259-267, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23993294

RESUMEN

Asthma is a serious health problem worldwide, particularly in industrialized countries. Despite a better understanding of the pathophysiology of asthma, there are still considerable gaps in knowledge as well as a need for classes of drugs. ASHMI™ (Anti-asthma Herbal Medicine Intervention) is an aqueous extract of Ganoderma lucidum (Fr.) P. Karst (Ling Zhi), Sophora flavescens Aiton (Ku Shen) and Glycyrrhiza uralensis Fisch. ex DC (Gan Cao). It prevents allergic asthma airway hyper-reactivity in mice and inhibits acetylcholine (ACh) induced airway smooth muscle (ASM) contraction in tracheal rings from allergic asthmatic mice. The purpose of this research was to identify individual herb(s) and their active compound(s) that inhibit ASM contraction. It was found that S. flavescens, but not G. lucidum or G. uralensis aqueous extracts, inhibited ASM contraction in tracheal rings from asthmatic mice. Bioassay-guided isolation and identification of flavonoid fractions/compound(s) via methylene chloride extraction, preparative HPLC fractionation, and LC-MS and NMR spectroscopic analyses showed that trifolirhizin is an active constituent that inhibits acetylcholine mediated ASM contraction or directly relaxes pre-contracted ASM independent of ß2-adrenoceptors.


Asunto(s)
Asma/fisiopatología , Flavonoides/farmacología , Glucósidos/farmacología , Compuestos Heterocíclicos de 4 o más Anillos/farmacología , Contracción Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Sophora/química , Tráquea/efectos de los fármacos , Acetilcolina/metabolismo , Animales , Asma/tratamiento farmacológico , Asma/metabolismo , Ganoderma , Glycyrrhiza , Ratones , Fitoterapia , Extractos Vegetales/farmacología
15.
J Allergy Clin Immunol ; 123(2): 297-306; quiz 307-8, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19203653

RESUMEN

BACKGROUND: Although corticosteroids and beta(2)-agonists are effective in managing asthma symptoms, a curative therapy for asthma is lacking. Traditional Chinese medicine (TCM), used in Asia for centuries, is beginning to play a role in Western health care as a complementary and alternative medicine modality. There is increasing scientific evidence supporting the use of TCM for asthma treatment. OBJECTIVE: This review article discusses promising TCM interventions for asthma and explores their possible mechanisms of action. METHODS: We first reviewed 5 clinical studies of antiasthma TCM herbal remedies published between 2005 and 2007. We then summarized possible mechanisms underlying their effects on the basis of data in the original articles, published abstracts, and available databases. Possible mechanisms include anti-inflammation, inhibition of airway smooth muscle contraction, and immunomodulation. Research on TCM herbal therapy for food allergy is rare, and we therefore focused on the effect and mechanism of action of food allergy herbal formula-2 on a murine model of peanut allergy and preliminary clinical study results. CONCLUSION: Evidence from clinical studies supports beneficial effects of TCM herbal therapy on asthma. A number of mechanisms may be responsible for efficacy of these agents. Strong preclinical study data suggest the potential efficacy of food allergy herbal formula-2 for food allergy.


Asunto(s)
Antialérgicos/farmacología , Antiasmáticos/farmacología , Asma/tratamiento farmacológico , Medicamentos Herbarios Chinos/farmacología , Hipersensibilidad a los Alimentos/tratamiento farmacológico , Factores Inmunológicos/farmacología , Medicina Tradicional China , Animales , Antialérgicos/uso terapéutico , Antiasmáticos/uso terapéutico , Asma/inmunología , Medicamentos Herbarios Chinos/uso terapéutico , Hipersensibilidad a los Alimentos/inmunología , Humanos , Factores Inmunológicos/uso terapéutico , Ratones , Fitoterapia
16.
J Neurochem ; 91(3): 600-12, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15485491

RESUMEN

A novel series of compounds derived from the high-affinity nicotinic acetylcholine receptor (nAChR) ligand, 5-(2-(4-pyridinyl)vinyl)-6-chloro-3-((1-methyl-2-(S)-pyrrolidinyl)methoxy)pyridine (Me-p-PVC), originally developed by Abbott Laboratories, was characterized in vitro in nAChR binding assays at 37 degrees C to show K(i) values in the range of 9-611 pm. Several compounds of this series were radiolabeled with (11)C and evaluated in vivo in mice and monkeys as potential candidates for PET imaging of nAChRs. [(11)C]Me-p-PVC (K(i) =56 pm at 37 degrees C; logD = 1.6) was identified as a radioligand suitable for the in vivo imaging of the alpha 4 beta 2* nAChR subtype. Compared with 2-[(18)F]FA, a PET radioligand that has been successfully used in humans and is characterized by a slow kinetic of brain distribution, [(11)C]Me-p-PVC is more lipophilic. As a result, [(11)C]Me-p-PVC accumulated in the brain more rapidly than 2-[(18)F]FA. Pharmacological evaluation of Me-p-PVC in mice demonstrated that the toxicity of this compound was comparable with or lower than that of 2-FA. Taken together, these results suggest that [(11)C]Me-p-PVC is a promising PET radioligand for studying nAChR occupancy by endogenous and exogenous ligands in the brain in vivo.


Asunto(s)
Unión Competitiva , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Tomografía de Emisión de Positrones/métodos , Piridinas/farmacocinética , Pirrolidinas/farmacocinética , Receptores Nicotínicos/metabolismo , Animales , Azetidinas/farmacocinética , Unión Competitiva/efectos de los fármacos , Radioisótopos de Carbono/química , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Macaca mulatta , Masculino , Ratones , Piridinas/química , Piridinas/farmacología , Pirrolidinas/química , Pirrolidinas/farmacología , Ratas , Receptores Nicotínicos/efectos de los fármacos
17.
J Med Chem ; 47(10): 2453-65, 2004 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-15115389

RESUMEN

Potential positron emission tomography (PET) ligands with low picomolar affinity at the nicotinic acetylcholine receptor (nAChR) and with lipophilicity (log D) ranging from -1.6 to +1.5 have been synthesized. Most members of the series, which are derivatives of 5-substituted-6-halogeno-A-85380, exhibited a higher binding affinity at alpha4beta2-nAChRs than epibatidine. An analysis, by molecular modeling, revealed an important role of the orientation of the additional heterocyclic ring on the binding affinity of the ligands with nAChRs. The existing nicotinic pharmacophore models do not accommodate this finding. Two compounds of the series, 6-[(18)F]fluoro-5-(pyridin-3-yl)-A-85380 ([(18)F]31) and 6-chloro-3-((2-(S)-azetidinyl)methoxy)-5-(2-[(18)F]fluoropyridin-5-yl)pyridine) ([(18)F]35), were radiolabeled with (18)F. Comparison of PET data for [(18)F]31 and 2-[(18)F]FA shows the influence of lipophilicity on the binding potential. Our recent PET studies with [(18)F]35 demonstrated that its binding potential values in Rhesus monkey brain were ca. 2.5 times those of 2-[(18)F]FA. Therefore, [(18)F]35 and several other members of the series, when radiolabeled, will be suitable for quantitative imaging of extrathalamic nAChRs.


Asunto(s)
Azetidinas/síntesis química , Piridinas/síntesis química , Pirrolidinas/síntesis química , Radiofármacos/síntesis química , Receptores Nicotínicos/metabolismo , Animales , Azetidinas/química , Azetidinas/farmacología , Unión Competitiva , Encéfalo/metabolismo , Radioisótopos de Flúor , Técnicas In Vitro , Marcaje Isotópico , Ligandos , Macaca mulatta , Modelos Moleculares , Piridinas/química , Piridinas/farmacología , Pirrolidinas/química , Pirrolidinas/farmacología , Ensayo de Unión Radioligante , Radiofármacos/química , Radiofármacos/farmacología , Ratas , Ratas Sprague-Dawley , Estereoisomerismo , Relación Estructura-Actividad , Tomografía Computarizada de Emisión/métodos
18.
J Med Chem ; 45(13): 2841-9, 2002 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-12061886

RESUMEN

Reportedly, 2-[(18)F]fluoro-A-85380, 1, a promising radiotracer for imaging the nicotinic acetylcholine receptor (nAChR) by positron emission tomography (PET) in humans, exhibits slow penetration through the blood-brain barrier (BBB) due to its low lipophilicity. A ligand for nAChRs with greater lipophilicity than that of 1 would be potentially more favorable for PET imaging of nAChR due to its faster penetration through the BBB. Herein, a novel series of compounds has been developed based on the high affinity ligand for nAChRs, 2-chloro-5-((1-methyl-2-(S)-pyrrolidinyl)methoxy)-3-(2-(4-pyridinyl)vinyl)pyridine, 3b. The in vitro binding affinities for the new series were found to be in the range of K(i) = 9-331 pM. A molecular modeling study showed differences in the comformational profiles and the electronic properties of these compounds, which provides further insight into the structure-activity relationships at nAChR. Lipophilicities of the compounds 3b-6b have been found to be substantially higher than that of 1. As a result, compounds 3b-6b might exhibit a faster penetration through the BBB than the less lipophilic 1. The N-methyl derivatives 3b and 6b demonstrated very high affinities at nAChRs (K(i) = 28 and 23 pM, respectively) and will be targets for development of (11)CH(3)-labeled derivatives as radiotracers for PET imaging of nAChRs.


Asunto(s)
Piridinas/síntesis química , Pirrolidinas/síntesis química , Receptores Nicotínicos/metabolismo , Animales , Unión Competitiva , Encéfalo/metabolismo , Técnicas In Vitro , Ligandos , Modelos Moleculares , Conformación Molecular , Piridinas/química , Piridinas/farmacología , Pirrolidinas/química , Pirrolidinas/farmacología , Ensayo de Unión Radioligante , Ratas , Relación Estructura-Actividad , Tomografía Computarizada de Emisión
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