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1.
Neuron ; 105(4): 663-677.e8, 2020 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-31837915

RESUMO

A major function of GPCRs is to inhibit presynaptic neurotransmitter release, requiring ligand-activated receptors to couple locally to effectors at terminals. The current understanding of how this is achieved is through receptor immobilization on the terminal surface. Here, we show that opioid peptide receptors, GPCRs that mediate highly sensitive presynaptic inhibition, are instead dynamic in axons. Opioid receptors diffuse rapidly throughout the axon surface and internalize after ligand-induced activation specifically at presynaptic terminals. We delineate a parallel regulated endocytic cycle for GPCRs operating at the presynapse, separately from the synaptic vesicle cycle, which clears activated receptors from the surface of terminals and locally reinserts them to maintain the diffusible surface pool. We propose an alternate strategy for achieving local control of presynaptic effectors that, opposite to using receptor immobilization and enforced proximity, is based on lateral mobility of receptors and leverages the inherent allostery of GPCR-effector coupling.


Assuntos
Endocitose/fisiologia , Terminações Pré-Sinápticas/metabolismo , Receptores Acoplados a Proteínas-G/metabolismo , Vesículas Sinápticas/metabolismo , Analgésicos Opioides/farmacologia , Animais , Células Cultivadas , Endocitose/efeitos dos fármacos , Ala(2)-MePhe(4)-Gly(5)-Encefalina/farmacologia , Terminações Pré-Sinápticas/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Transporte Proteico/fisiologia , Ratos , Ratos Sprague-Dawley , Receptores Acoplados a Proteínas-G/agonistas , Receptores de Neurotransmissores/agonistas , Receptores de Neurotransmissores/metabolismo , Vesículas Sinápticas/efeitos dos fármacos
2.
Mol Pharm ; 17(1): 32-39, 2020 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-31765157

RESUMO

Obesity and metabolic syndrome are threats to the health of large population worldwide as they are associated with high mortality, mainly linked to cardiovascular diseases. Recently, CPN-116 (CPN), which is an agonist peptide specific to neuromedin-U receptor 2 (NMUR2) that is expressed predominantly in the brain, has been developed as a new therapeutic candidate for the treatment of obesity and metabolic syndrome. However, treatment with CPN poses a challenge due to the limited delivery of CPN to the brain. Recent studies have clarified that the direct anatomical connection of the nasal cavity with brain allows delivery of several drugs to the brain. In this study, we confirm the nasal cavity as a promising CPN delivery route to the brain for the treatment of obesity and metabolic syndrome. According to the pharmacokinetic study, the clearance of CPN from the blood was very rapid with a half-life of 3 min. In vitro study on its stability in the serum and cerebrospinal fluid (CSF) indicates that CPN was more stable in the CSF than in the blood. The concentration of CPN in the brain was higher after nasal administration, despite its lower concentrations in the plasma than that after intravenous administration. The study on its pharmacological potency suggests the effective suppression of increased body weight in mice in a dose-dependent manner due to the direct activation of NMUR2 by CPN. This results from the higher concentration of corticosterone in blood after nasal administration of CPN as compared to nasal application of saline. In conclusion, the above findings indicate that the nasal cavity is a promising CPN delivery route to the brain to treat obesity and metabolic syndrome.


Assuntos
Fármacos Antiobesidade/administração & dosagem , Encéfalo/efeitos dos fármacos , Obesidade/tratamento farmacológico , Peptídeos/administração & dosagem , Receptores de Neurotransmissores/agonistas , Administração Intranasal , Animais , Fármacos Antiobesidade/sangue , Fármacos Antiobesidade/líquido cefalorraquidiano , Fármacos Antiobesidade/farmacocinética , Corticosterona/sangue , Células HEK293 , Humanos , Camundongos , Obesidade/sangue , Obesidade/líquido cefalorraquidiano , Peptídeos/sangue , Peptídeos/líquido cefalorraquidiano , Peptídeos/farmacocinética , Ratos , Ratos Wistar
3.
Yakugaku Zasshi ; 139(11): 1377-1384, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31685733

RESUMO

Biomolecule-derived peptides are attractive research resources to develop drugs and elucidate the basic mechanisms of life phenomena. This review article focuses on two biomolecules called "neuromedin U (NMU)" and "myostatin" that are deeply involved in obesity and muscle weakness caused by modern lifestyles and aging. A structure-activity relationship (SAR) study based on a biomolecule reveals the structural features required for the biological activity and gives clues leading the drug discovery process. NMU activates two types of receptors (NMUR1 and NMUR2). NMU, which is an attractive candidate for treating obesity, displays a variety of physiological actions in addition to appetite suppression. The discovery of useful receptor-selective agonists helps in elucidating the detailed roles of the respective receptors for each action and in developing therapeutic drugs based on receptor function. Hence, SAR studies focused on the amidated C-terminal heptapeptide of NMU were carried out to obtain selective agonists. Consequently, the respective hexapeptidic NMUR1 and NMUR2 agonists CPN-267 and CPN-116 were discovered. Myostatin, an endogenous negative regulator of skeletal muscle mass, is a promising target for treating muscle atrophy disorders. Focused on the inactivation mechanism of mature myostatin by the myostatin precursor-derived prodomain, a core peptide (23-mer) for effective myostatin inhibition was identified from the mouse myostatin prodomain sequence. The SAR study based on this core peptide afforded a 25-fold more potent derivative (16-mer), which increased skeletal muscle mass and hindlimb grip strength. Therefore, this derivative could be a novel platform for a peptidic drug useful in the treatment of muscle atrophy.


Assuntos
Química Farmacêutica , Descoberta de Drogas , Miostatina/química , Neuropeptídeos/química , Peptídeos/química , Envelhecimento , Humanos , Estilo de Vida , Terapia de Alvo Molecular , Debilidade Muscular , Atrofia Muscular/terapia , Neuropeptídeos/uso terapêutico , Obesidade/tratamento farmacológico , Receptores de Neurotransmissores/agonistas , Relação Estrutura-Atividade
4.
Pharmacol Rev ; 71(4): 520-538, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31530573

RESUMO

Chromosome conformation capture methods have revealed the dynamics of genome architecture which is spatially organized into topologically associated domains, with gene regulation mediated by enhancer-promoter pairs in chromatin space. New evidence shows that endogenous hormones and several xenobiotics act within circumscribed topological domains of the spatial genome, impacting subsets of the chromatin contacts of enhancer-gene promoter pairs in cis and trans Results from the National Institutes of Health-funded PsychENCODE project and the study of chromatin remodeling complexes have converged to provide a clearer understanding of the organization of the neurogenic epigenome in humans. Neuropsychiatric diseases, including schizophrenia, bipolar spectrum disorder, autism spectrum disorder, attention deficit hyperactivity disorder, and other neuropsychiatric disorders are significantly associated with mutations in neurogenic transcriptional networks. In this review, we have reanalyzed the results from publications of the PsychENCODE Consortium using pharmacoinformatics network analysis to better understand druggable targets that control neurogenic transcriptional networks. We found that valproic acid and other psychotropic drugs directly alter these networks, including chromatin remodeling complexes, transcription factors, and other epigenetic modifiers. We envision a new generation of CNS therapeutics targeted at neurogenic transcriptional control networks, including druggable parts of chromatin remodeling complexes and master transcription factor-controlled pharmacogenomic networks. This may provide a route to the modification of interconnected gene pathways impacted by disease in patients with neuropsychiatric and neurodegenerative disorders. Direct and indirect therapeutic strategies to modify the master regulators of neurogenic transcriptional control networks may ultimately help extend the life span of CNS neurons impacted by disease.


Assuntos
Redes Reguladoras de Genes/efeitos dos fármacos , Transcrição Genética/efeitos dos fármacos , Sistema Nervoso Central/efeitos dos fármacos , Sistema Nervoso Central/fisiologia , Cromatina/efeitos dos fármacos , Cromatina/genética , Cromatina/metabolismo , Epigênese Genética , Genoma Humano/efeitos dos fármacos , Humanos , Receptores de Neurotransmissores/agonistas , Receptores de Neurotransmissores/antagonistas & inibidores , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
5.
Cell Host Microbe ; 26(2): 273-282.e7, 2019 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-31378678

RESUMO

Despite evidence linking the human microbiome to health and disease, how the microbiota affects human physiology remains largely unknown. Microbiota-encoded metabolites are expected to play an integral role in human health. Therefore, assigning function to these metabolites is critical to understanding these complex interactions and developing microbiota-inspired therapies. Here, we use large-scale functional screening of molecules produced by individual members of a simplified human microbiota to identify bacterial metabolites that agonize G-protein-coupled receptors (GPCRs). Multiple metabolites, including phenylpropanoic acid, cadaverine, 9-10-methylenehexadecanoic acid, and 12-methyltetradecanoic acid, were found to interact with GPCRs associated with diverse functions within the nervous and immune systems, among others. Collectively, these metabolite-receptor pairs indicate that diverse aspects of human health are potentially modulated by structurally simple metabolites arising from primary bacterial metabolism.


Assuntos
Bactérias/metabolismo , Interações entre Hospedeiro e Microrganismos/imunologia , Interações entre Hospedeiro e Microrganismos/fisiologia , Microbiota/imunologia , Microbiota/fisiologia , Receptores Acoplados a Proteínas-G/agonistas , Proteínas Angiogênicas/agonistas , Animais , Cadaverina/metabolismo , Cadaverina/farmacologia , Ácidos Graxos/metabolismo , Ácidos Graxos/farmacologia , Fermentação , Vida Livre de Germes , Agonistas dos Receptores Histamínicos , Humanos , Sistema Imunitário , Ligantes , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , Propionatos/metabolismo , Propionatos/farmacologia , Receptores Acoplados a Proteínas-G/metabolismo , Receptores Histamínicos/efeitos dos fármacos , Receptores de Neurotransmissores/agonistas
6.
Cell Microbiol ; 21(9): e13044, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31099148

RESUMO

Staphylococcus aureus is a facultative intracellular pathogen that invades a wide range of professional and nonprofessional phagocytes by triggering internalisation by interaction of surface-bound adhesins with corresponding host cell receptors. Here, we identified a new concept of host cell internalisation in animal-pathogenic staphylococcal species. This new mechanism exemplified by Staphylococcus pseudintermedius ED99 is not based on surface-bound adhesins but is due to excreted small neurochemical compounds, such as trace amines (TAs), dopamine (DOP), and serotonin (SER), that render host cells competent for bacterial internalisation. The neurochemicals are produced by only one enzyme, the staphylococcal aromatic amino acid decarboxylase (SadA). Here, we unravelled the mechanism of how neurochemicals trigger internalisation into the human colon cell line HT-29. We found that TAs and DOP are agonists of the α2-adrenergic receptor, which, when activated, induces a cascade of reactions involving a decrease in the cytoplasmic cAMP level and an increase in F-actin formation. The signalling cascade of SER follows a different pathway. SER interacts with 5HT receptors that trigger F-actin formation without decreasing the cytoplasmic cAMP level. The neurochemical-induced internalisation in host cells is independent of the fibronectin-binding protein pathway and has an additive effect. In a sadA deletion mutant, ED99ΔsadA, internalisation was decreased approximately threefold compared with that of the parent strain, and treating S. aureus USA300 with TAs increased internalisation by approximately threefold.


Assuntos
Descarboxilases de Aminoácido-L-Aromático/metabolismo , Células Epiteliais/metabolismo , Neurotransmissores/farmacologia , Staphylococcus/enzimologia , Actinas/metabolismo , Agonistas de Receptores Adrenérgicos alfa 2/farmacologia , Antagonistas de Receptores Adrenérgicos alfa 2/farmacologia , Adulto , Idoso , Animais , Descarboxilases de Aminoácido-L-Aromático/genética , Linhagem Celular Tumoral , AMP Cíclico/metabolismo , Citoplasma/metabolismo , Dopamina/metabolismo , Dopamina/farmacologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/microbiologia , Fibronectinas/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Neurotransmissores/metabolismo , Receptores Adrenérgicos alfa 2/metabolismo , Receptores de Neurotransmissores/agonistas , Receptores de Neurotransmissores/metabolismo , Serotonina/metabolismo , Serotonina/farmacologia , Transdução de Sinais , Staphylococcus/efeitos dos fármacos , Staphylococcus/metabolismo , Staphylococcus/patogenicidade , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/metabolismo , Staphylococcus aureus/patogenicidade
7.
Biomolecules ; 9(4)2019 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-30970612

RESUMO

Levodopa (LD) is the most effective drug in the treatment of Parkinson's disease (PD). However, although it represents the "gold standard" of PD therapy, LD can cause side effects, including gastrointestinal and cardiovascular symptoms as well as transient elevated liver enzyme levels. Moreover, LD therapy leads to LD-induced dyskinesia (LID), a disabling motor complication that represents a major challenge for the clinical neurologist. Due to the many limitations associated with LD therapeutic use, other dopaminergic and non-dopaminergic drugs are being developed to optimize the treatment response. This review focuses on recent investigations about non-dopaminergic central nervous system (CNS) receptor ligands that have been identified to have therapeutic potential for the treatment of motor and non-motor symptoms of PD. In a different way, such agents may contribute to extending LD response and/or ameliorate LD-induced side effects.


Assuntos
Antiparkinsonianos/efeitos adversos , Levodopa/efeitos adversos , Neurotransmissores/efeitos adversos , Doença de Parkinson/tratamento farmacológico , Receptores de Neurotransmissores/metabolismo , Animais , Antiparkinsonianos/uso terapêutico , Discinesia Induzida por Medicamentos/tratamento farmacológico , Discinesia Induzida por Medicamentos/etiologia , Humanos , Levodopa/uso terapêutico , Neurotransmissores/uso terapêutico , Receptores de Neurotransmissores/agonistas , Receptores de Neurotransmissores/antagonistas & inibidores
8.
Pharmacol Res Perspect ; 6(5): e00425, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30151213

RESUMO

Obesity is a growing public health concern, with 37.5% of the adult population in need of therapeutics that are more efficacious with a better side effect profile. An innovative target in this regard is neuromedin U, a neuropeptide shown to suppress food intake and attenuate weight gain in animal models. These effects of neuromedin U on feeding behavior are thought to be related to agonism at the centrally expressed neuromedin U receptor 2 (NMUR2). As peptides present unique challenges that limit their therapeutic potential, the discovery of small-molecule NMUR2 agonists is needed to validate the targets therapeutic value, but to date, none have been evaluated in any animal model of disease. We therefore assessed two small-molecule NMUR2 agonists for their in vitro signaling and their in vivo efficacy. The NMUR2 agonists were synthesized and both NMUR2 agonists, NY0116 and NY0128, decreased cAMP while stimulating calcium signaling in stably expressing NMUR2 HEK293 cells. When small-molecule NMUR2 agonists were tested in vivo, acute administration significantly decreased high-fat diet consumption. Repeated administration of the compounds decreased body weight and more specifically, decreased the percentage of visceral adipose tissue (VAT) in obese mice. These results have confirmed small-molecule NMUR2 agonists are efficacious in animal models to decrease fat content, food intake, and body weight, suggesting NMUR2 is a promising therapeutic target for metabolic disorders.


Assuntos
Fármacos Antiobesidade/farmacologia , Ingestão de Alimentos/efeitos dos fármacos , Gordura Intra-Abdominal/efeitos dos fármacos , Obesidade/tratamento farmacológico , Receptores de Neurotransmissores/agonistas , Adulto , Animais , Fármacos Antiobesidade/síntese química , Fármacos Antiobesidade/uso terapêutico , Peso Corporal/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Células HEK293 , Humanos , Masculino , Camundongos Endogâmicos C57BL , Neuropeptídeos/metabolismo , Obesidade/etiologia , Ratos , Ratos Sprague-Dawley , Resultado do Tratamento
9.
Eur J Med Chem ; 144: 887-897, 2018 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-29329072

RESUMO

Neuromedin U (NMU) is a highly conserved endogenous peptide that is involved in a wide range of physiological processes such as regulation of feeding behavior, the stress response and nociception. The major limitation to use NMU as a therapeutic is its short half-life. Here, we describe the development of a set of novel NMU-analogs based on NMU-8, by introducing unnatural amino acids into the native sequence. This approach shows that it is possible to generate molecules with increased potency and improved plasma stability without major changes of the peptidic nature or the introduction of large conjugates. When compared to the native NMU-8 peptide, compounds 16, 18 and 20 have potent agonist activity and affinity for both NMU receptors. Selectivity towards NMUR1 was observed when the Phe residue in position 4 was modified, whereas higher potencies at NMUR2 were found when substitutions of the Pro residue in position 6 were executed. To study the effect of the modifications on the proteolytic stability of the molecules, an in vitro stability assay in human plasma at 37 °C was performed. All analyzed analogs possessed an increased resistance against enzymatic degradation in human plasma resulting in half-lifes from 4 min for NMU-8, up to more than 23 h for compound 42.


Assuntos
Neuropeptídeos/farmacologia , Proteólise/efeitos dos fármacos , Receptores de Neurotransmissores/agonistas , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Neuropeptídeos/síntese química , Neuropeptídeos/química , Relação Estrutura-Atividade
10.
Br J Pharmacol ; 175(2): 359-373, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29057457

RESUMO

BACKGROUND AND PURPOSE: Neuromedin U (NmU) may be a novel target for obesity treatment owing to its anorectic and energy expenditure enhancing effects. Although two receptors, NMU1 and NMU2, are both responsible for the NmU-mediated anti-obesity effects, the receptor agonist with the most appropriate profiles for treating obesity and diabetes in terms of efficacy and safety is as yet unknown. Thus, we developed and evaluated novel NMU1/2 receptor-selective agonists. EXPERIMENTAL APPROACH: Efficacy and safety were assessed in mice with diet-induced obesity (DIO) and those with leptin-deficient diabetes (ob/ob) through repeated peripheral administration of selective agonists to NMU1 (NMU-6102) and NMU2 (NMU-2084), along with non-selective NMU1/2 agonists (NMU-0002 and NMU-6014). We also performed immunohistochemistry for c-Fos protein expression in the brain to probe their mechanisms of action. KEY RESULTS: Although both non-selective NMU1/2 agonists and the NMU2-selective agonist had high efficacy compared with the NMU1-selective agonist, only the NMU2-selective agonist led to relatively low adverse effects, such as diarrhoea, in DIO mice. However, the non-selective NMU1/2 agonist and the NMU1-selective agonist, but not the NMU2-selective agonist, were effective in diabetic ob/ob mice. Mechanistically, NMU2-selective agonists preferentially activate pro-opiomelanocortin neurons in the hypothalamic arcuate nucleus but not in the paraventricular nucleus. CONCLUSIONS AND IMPLICATIONS: These results suggest that an NMU2 receptor-selective agonist may be a well-balanced drug for the treatment of obesity and that an NMU1 receptor-selective agonist may also be beneficial for treating obesity and diabetes once its side effects are minimized.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Obesidade/tratamento farmacológico , Oligopeptídeos/efeitos adversos , Oligopeptídeos/uso terapêutico , Receptores de Neurotransmissores/agonistas , Animais , Núcleo Arqueado do Hipotálamo/fisiologia , Encéfalo/metabolismo , Masculino , Camundongos , Núcleo Hipotalâmico Paraventricular/fisiologia , Proteínas Proto-Oncogênicas c-fos/metabolismo
11.
Behav Brain Res ; 334: 129-134, 2017 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-28760699

RESUMO

The insular cortex (IC) receives projections from prefrontal, entorhinal and cingulate cortex, olfactory bulb and basal nuclei and has reciprocal connections with the amygdala and entorhinal cortex. These connections suggest a possible involvement in memory processes; this has been borne out by data on several behaviors. Social recognition memory (SRM) is essential to form social groups and to establish hierarchies and social and affective ties. Despite its importance, knowledge about the brain structures and the neurotransmitter mechanisms involved in its processing is still scarce. Here we study the participation of NMDA-glutamatergic, D1/D5-dopaminergic, H2-histaminergic, ß-adrenergic and 5-HT1A-serotoninergic receptors of the IC in the consolidation of SRM. Male Wistar rats received intra-IC infusions of substances acting on these receptors immediately after the sample phase of a social discrimination task and 24h later were exposed to a 5-min retention test. The intra-IC infusion of antagonists of D1/D5, ß-adrenergic or 5-HT1A receptors immediately after the sample phase impaired the consolidation of SRM. These effects were blocked by the concomitant intra-IC infusion of agonists of these receptors. Antagonists and agonists of NMDA and H2 receptors had no effect on SRM. The results suggest that the dopaminergic D1/D5, ß-adrenergic and serotonergic 5-HT1A receptors in the IC, but not glutamatergic NMDA and the histaminergic H2 receptors, participate in the consolidation of SRM in the IC.


Assuntos
Córtex Cerebral/metabolismo , Consolidação da Memória/fisiologia , Receptores de Neurotransmissores/metabolismo , Reconhecimento Psicológico/fisiologia , Percepção Social , Animais , Cateteres de Demora , Córtex Cerebral/efeitos dos fármacos , Discriminação Psicológica/efeitos dos fármacos , Discriminação Psicológica/fisiologia , Comportamento Exploratório/efeitos dos fármacos , Comportamento Exploratório/fisiologia , Masculino , Consolidação da Memória/efeitos dos fármacos , Neurotransmissores/farmacologia , Testes Psicológicos , Ratos Wistar , Receptores de Neurotransmissores/agonistas , Receptores de Neurotransmissores/antagonistas & inibidores , Reconhecimento Psicológico/efeitos dos fármacos
12.
Int J Obes (Lond) ; 41(12): 1790-1797, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28757640

RESUMO

BACKGROUND: Neuromedin U (NMU) is a neuropeptide with various physiological functions, including regulation of smooth-muscle contraction, blood pressure, stress responses and feeding behaviors. NMU activates two distinct receptors, NMUR1 and NMUR2, which are predominantly expressed in peripheral tissues and the central nervous system (CNS), respectively. It is reported that the NMU signaling system regulates food intake (FI) and body weight (BW) via NMUR2, suggesting that an NMUR2 agonist exhibiting anorectic effects would be a potential therapy for obesity. METHODS: Antiobesity effects of NMUR2 activation were assessed using a recently developed, novel NMUR2-selective agonist, NMU-7005 (a polyethylene glycolated octapeptide). Here we assessed cumulative FI and BW loss after peripheral administration of NMU-7005 in NMUR2 knockout and diet-induced obese mice. To gain mechanistic insights, we performed immunohistochemical analysis of c-Fos-like protein expression in the brain. RESULTS: We found that NMU-7005 was a NMUR2-selective agonist with little activity toward NMUR1. The anorectic effect of NMU-7005 was completely abrogated in NMUR2 knockout mice. Repeated subcutaneous administration of NMU-7005 showed a potent antiobesity effect with FI inhibition (P<0.025) in diet-induced obese mice. NMU-7005 in combination with the glucagon-like peptide-1 receptor (GLP-1R) agonist liraglutide showed an additive antiobesity effect, suggesting that NMUR2-mediated anorectic action is different from that of GLP-1R agonists. NMU-7005 also elicited a minimal conditioned taste-aversive effect, while the effect of liraglutide was significant. As c-Fos expression was upregulated in the hypothalamus and the medulla oblongata in NMU-7005-administered mice, the pharmacological effects of NMU-7005 appeared to be mediated via activation of the CNS. CONCLUSION: Our results demonstrated that a novel NMUR2-selective agonist, NMU-7005, is a beneficial tool for the elucidation of NMUR2-mediated physiological functions, which is a promising therapeutic strategy for treating obesity.


Assuntos
Fármacos Antiobesidade/farmacologia , Peso Corporal/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Liraglutida/farmacologia , Neuropeptídeos/farmacologia , Obesidade/tratamento farmacológico , Receptores de Neurotransmissores/agonistas , Animais , Modelos Animais de Doenças , Comportamento Alimentar , Imuno-Histoquímica , Camundongos , Camundongos Obesos
13.
Sci Rep ; 7(1): 9037, 2017 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-28831096

RESUMO

During acute neuroinflammation, increased levels of cytokines within the brain may contribute to synaptic reorganization that results in long-term changes in network hyperexcitability. Indeed, inflammatory cytokines are implicated in synaptic dysfunction in epilepsy and in an array of degenerative and autoimmune diseases of the central nervous system. Current tools for studying the impact of inflammatory factors on neural networks are either insufficiently fast and sensitive or require complicated and costly experimental rigs. Calcium imaging offers a reasonable surrogate for direct measurement of neuronal network activity, but traditional imaging paradigms are confounded by cellular heterogeneity and cannot readily distinguish between glial and neuronal calcium transients. While the establishment of pure neuron cultures is possible, the removal of glial cells ignores physiologically relevant cell-cell interactions that may be critical for circuit level disruptions induced by inflammatory factors. To overcome these issues, we provide techniques and algorithms for image processing and waveform feature extraction using automated analysis of spontaneous and evoked calcium transients in primary murine cortical neuron cultures transduced with an adeno-associated viral vector driving the GCaMP6f reporter behind a synapsin promoter. Using this system, we provide evidence of network perturbations induced by the inflammatory cytokines TNFα, IL1ß, and IFNγ.


Assuntos
Cálcio/metabolismo , Córtex Cerebral/citologia , Córtex Cerebral/patologia , Citocinas/metabolismo , Imagem Molecular , Vias Neurais , Neurônios/fisiologia , Animais , Biomarcadores , Sinalização do Cálcio , Células Cultivadas , Imunofluorescência , Expressão Gênica , Mediadores da Inflamação/metabolismo , Camundongos , Rede Nervosa , Neurônios/efeitos dos fármacos , Receptores de Neurotransmissores/agonistas , Receptores de Neurotransmissores/antagonistas & inibidores
14.
J Med Chem ; 60(14): 6089-6097, 2017 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-28657315

RESUMO

Neuromedin U (NMU) is a neuropeptide that mediates a variety of physiological functions via its receptors, NMUR1 and NMUR2. Recently, there has been an increased focus on NMU as a promising treatment option for diabetes and obesity. A short form of NMU (NMU-8) has potent agonist activity for both receptors but is metabolically unstable. Therefore, we designed and synthesized NMU-8 analogues modified by polyethylene glycol (PEG; molecular weight, 20 kDa; PEG20k) via a linker. 3-(2-Naphthyl)alanine substitution at position 19 increased NMUR2 selectivity of NMU-8 analogues with retention of high agonist activity. Compound 37, an NMUR2-selective PEG20k analogue containing piperazin-1-ylacetyl linker, exhibited a potent body weight-lowering effect with concomitant inhibition of food intake in a dose-dependent manner (body weight loss of 12.4% at 30 nmol/kg) by once-daily repeated dosing for 2 weeks in mice with diet-induced obesity.


Assuntos
Fármacos Antiobesidade/síntese química , Neuropeptídeos/química , Obesidade/tratamento farmacológico , Fragmentos de Peptídeos/síntese química , Polietilenoglicóis/química , Receptores de Neurotransmissores/agonistas , Animais , Fármacos Antiobesidade/farmacocinética , Fármacos Antiobesidade/farmacologia , Peso Corporal/efeitos dos fármacos , Gorduras na Dieta/administração & dosagem , Masculino , Camundongos Endogâmicos C57BL , Naftalenos/síntese química , Naftalenos/farmacocinética , Naftalenos/farmacologia , Obesidade/fisiopatologia , Fragmentos de Peptídeos/farmacocinética , Fragmentos de Peptídeos/farmacologia , Piperazinas/síntese química , Piperazinas/farmacocinética , Piperazinas/farmacologia , Relação Estrutura-Atividade
15.
J Med Chem ; 60(12): 5228-5234, 2017 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-28548497

RESUMO

Neuromedin U (NMU) activates two NMU receptors (NMUR1 and NMUR2) and is a useful antiobesity drug lead. We report discovery of a hexapeptide agonist, 2-thienylacetyl-Trp1-Phe(4-F)2-Arg3-Pro4-Arg5-Asn6-NH2 (4). However, the NMUR1 selectivity and serum stability of this agonist were unsatisfactory. Through a structure-activity relationship study focused on residue 2 of agonist 4, serum stability, and pharmacokinetic properties, we report here the discovery of a novel NMUR1 selective hexapeptide agonist 7b that suppresses body weight gain in mice.


Assuntos
Peptídeos/farmacologia , Receptores de Neurotransmissores/agonistas , Ganho de Peso/efeitos dos fármacos , Animais , Cálcio/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Estabilidade de Medicamentos , Humanos , Masculino , Peptídeos/sangue , Peptídeos/farmacocinética , Ratos Wistar
16.
Mol Diagn Ther ; 21(4): 357-373, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28197949

RESUMO

Next-generation sequencing (NGS) has contributed to the identification of many monogenic epilepsy syndromes and is favouring earlier and more accurate diagnosis in a subset of paediatric patients with epilepsy. The cumulative information emerging from NGS studies is rapidly changing our comprehension of the relations between early-onset severe epilepsy and the associated neurological impairment, progressively delineating specific entities previously gathered under the umbrella definition of epileptic encephalopathies, thereby influencing treatment choices and limiting the most aggressive drug regimens only to those conditions that are likely to actually benefit from them. Although ion channel genes represent the gene family most frequently causally related to epilepsy, other genes have gradually been associated with complex developmental epilepsy conditions, revealing the pathogenic role of mutations affecting diverse molecular pathways that regulate membrane excitability, synaptic plasticity, presynaptic neurotransmitter release, postsynaptic receptors, transporters, cell metabolism, and many formative steps in early brain development. Some of these discoveries are being followed by proof-of-concept laboratory studies that might open new pathways towards personalized treatment choices. No specific treatment is available for most of the monogenic disorders that can now be diagnosed early using NGS, and the main benefits of knowing the specific cause include etiological diagnosis, better prognostication and genetic counselling; however, for a limited number of disorders, timely treatment based on their known molecular pathology is already possible and sometimes decisive. Discovery of a causative gene defect associated with a non-progressive course may reduce the need for further diagnostic investigations in the search for a progressive disorder at the biochemical and imaging level. NGS has also improved the turnaround time for molecular diagnosis and allowed more timely and straightforward treatment choices for specific conditions as well as avoiding needless investigations and inappropriate or unnecessary treatment choices.


Assuntos
Anticonvulsivantes/uso terapêutico , Epilepsia/diagnóstico , Epilepsia/tratamento farmacológico , Sequenciamento de Nucleotídeos em Larga Escala/estatística & dados numéricos , Medicina de Precisão/métodos , Idade de Início , Criança , Diagnóstico Precoce , Epilepsia/genética , Epilepsia/fisiopatologia , Expressão Gênica , Aconselhamento Genético , Humanos , Canais Iônicos/agonistas , Canais Iônicos/antagonistas & inibidores , Canais Iônicos/genética , Canais Iônicos/metabolismo , Mutação , Plasticidade Neuronal/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Neurotransmissores/agonistas , Neurotransmissores/antagonistas & inibidores , Neurotransmissores/metabolismo , Receptores de Neurotransmissores/agonistas , Receptores de Neurotransmissores/antagonistas & inibidores , Receptores de Neurotransmissores/genética , Receptores de Neurotransmissores/metabolismo
17.
Neuron ; 89(4): 683-94, 2016 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-26889809

RESUMO

To understand brain function, it is essential that we discover how cellular signaling specifies normal and pathological brain function. In this regard, chemogenetic technologies represent valuable platforms for manipulating neuronal and non-neuronal signal transduction in a cell-type-specific fashion in freely moving animals. Designer Receptors Exclusively Activated by Designer Drugs (DREADD)-based chemogenetic tools are now commonly used by neuroscientists to identify the circuitry and cellular signals that specify behavior, perceptions, emotions, innate drives, and motor functions in species ranging from flies to nonhuman primates. Here I provide a primer on DREADDs highlighting key technical and conceptual considerations and identify challenges for chemogenetics going forward.


Assuntos
Desenho de Fármacos , Terapia de Alvo Molecular/métodos , Pesquisa Médica Translacional , Animais , Humanos , Ligantes , Receptores de Neurotransmissores/agonistas , Receptores de Neurotransmissores/antagonistas & inibidores , Receptores de Neurotransmissores/genética , Receptores de Neurotransmissores/metabolismo , Transdução de Sinais
18.
J Neurophysiol ; 115(2): 1031-42, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26581874

RESUMO

A pressing need in neurobiology is the comprehensive identification and characterization of neuronal subclasses within the mammalian nervous system. To this end, we used constellation pharmacology as a method to interrogate the neuronal and glial subclasses of the mouse cerebellum individually and simultaneously. We then evaluated the data obtained from constellation-pharmacology experiments by cluster analysis to classify cells into neuronal and glial subclasses, based on their functional expression of glutamate, acetylcholine, and GABA receptors, among other ion channels. Conantokin peptides were used to identify N-methyl-d-aspartate (NMDA) receptor subtypes, which revealed that neurons of the young mouse cerebellum expressed NR2A and NR2B NMDA receptor subunits. Additional pharmacological tools disclosed differential expression of α-amino-3-hydroxy-5-methyl-4-isoxazloepropionic, nicotinic acetylcholine, and muscarinic acetylcholine receptors in different neuronal and glial subclasses. Certain cell subclasses correlated with known attributes of granule cells, and we combined constellation pharmacology with genetically labeled neurons to identify and characterize Purkinje cells. This study illustrates the utility of applying constellation pharmacology to classify neuronal and glial subclasses in specific anatomical regions of the brain.


Assuntos
Cerebelo/citologia , Neuroglia/classificação , Neurônios/classificação , Potenciais de Ação , Animais , Células Cultivadas , Canais Iônicos/antagonistas & inibidores , Canais Iônicos/classificação , Camundongos , Camundongos Endogâmicos C57BL , Neuroglia/metabolismo , Neuroglia/fisiologia , Neurônios/metabolismo , Neurônios/fisiologia , Receptores de Neurotransmissores/agonistas , Receptores de Neurotransmissores/antagonistas & inibidores , Receptores de Neurotransmissores/classificação
19.
Bioorg Med Chem ; 22(21): 6117-23, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25262941

RESUMO

Central neuromedin U 2 receptor (NMU2R) plays important roles in the regulation of food intake and body weight. Identification of NMU2R agonists may lead to the development of pharmaceutical agents to treat obesity. Based on the structure of rutin, a typical flavonoid and one of the NMU2R agonists we previously identified from an in-house made natural product library, 30 flavonoid derivatives have been synthesized and screened on a cell-based reporter gene assay. A number of compounds were found to be selective and highly potent to NMU2R. For example, the EC50 value of compound NRA 4 is very close to that of NMU, the endogenous peptide ligand of NMU2R. Structure-activity relationship analysis revealed that a 3-hydroxyl group in ring C and a 2'-fluoride group in ring B were essential for this class of compounds to be active against NMU2R.


Assuntos
Flavonoides/química , Flavonoides/farmacologia , Receptores de Neurotransmissores/agonistas , Desenho de Fármacos , Flavonoides/síntese química , Humanos , Receptores de Neurotransmissores/metabolismo , Relação Estrutura-Atividade
20.
Annu Rev Neurosci ; 37: 387-407, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25002280

RESUMO

Elucidating the roles of neuronal cell types for physiology and behavior is essential for understanding brain functions. Perturbation of neuron electrical activity can be used to probe the causal relationship between neuronal cell types and behavior. New genetically encoded neuron perturbation tools have been developed for remotely controlling neuron function using small molecules that activate engineered receptors that can be targeted to cell types using genetic methods. Here we describe recent progress for approaches using genetically engineered receptors that selectively interact with small molecules. Called "chemogenetics," receptors with diverse cellular functions have been developed that facilitate the selective pharmacological control over a diverse range of cell-signaling processes, including electrical activity, for molecularly defined cell types. These tools have revealed remarkably specific behavioral physiological influences for molecularly defined cell types that are often intermingled with populations having different or even opposite functions.


Assuntos
Encéfalo/fisiologia , Engenharia Genética/métodos , Técnicas de Sonda Molecular , Receptores de Neurotransmissores/fisiologia , Animais , Humanos , Canais Iônicos/agonistas , Canais Iônicos/antagonistas & inibidores , Canais Iônicos/fisiologia , Ligantes , Sondas Moleculares/genética , Sondas Moleculares/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Receptores Acoplados a Proteínas-G/agonistas , Receptores Acoplados a Proteínas-G/antagonistas & inibidores , Receptores Acoplados a Proteínas-G/genética , Receptores Acoplados a Proteínas-G/fisiologia , Receptores de Neurotransmissores/agonistas , Receptores de Neurotransmissores/antagonistas & inibidores
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