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Artigos de revistas sobre o assunto "Neurones NPY/AgRP"

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Williams, Gareth, Joanne A. Harrold e David J. Cutler. "The hypothalamus and the regulation of energy homeostasis: lifting the lid on a black box". Proceedings of the Nutrition Society 59, n.º 3 (agosto de 2000): 385–96. http://dx.doi.org/10.1017/s0029665100000434.

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The hypothalamus is the focus of many peripheral signals and neural pathways that control energy homeostasis and body weight. Emphasis has moved away from anatomical concepts of ‘feeding’ and ‘satiety’ centres to the specific neurotransmitters that modulate feeding behaviour and energy expenditure. We have chosen three examples to illustrate the physiological roles of hypothalamic neurotransmitters and their potential as targets for the development of new drugs to treat obesity and other nutritional disorders. Neuropeptide Y (NPY) is expressed by neurones of the hypothalamic arcuate nucleus (ARC) that project to important appetite-regulating nuclei, including the paraventricular nucleus (PVN). NPY injected into the PVN is the most potent central appetite stimulant known, and also inhibits thermogenesis; repeated administration rapidly induces obesity. The ARC NPY neurones are stimulated by starvation, probably mediated by falls in circulating leptin and insulin (which both inhibit these neurones), and contribute to the increased hunger in this and other conditions of energy deficit. They therefore act homeostatically to correct negative energy balance. ARC NPY neurones also mediate hyperphagia and obesity in the ob/ob and db/db mice and fa/fa rat, in which leptin inhibition is lost through mutations affecting leptin or its receptor. Antagonists of the Y5 receptor (currently thought to be the NPY ‘feeding’ receptor) have anti-obesity effects. Melanocortin-4 receptors (MC4-R) are expressed in various hypothalamic regions, including the ventromedial nucleus and ARC. Activation of MC4-R by agonists such as α-melanocyte-stimulating hormone (a cleavage product of pro-opiomelanocortin which is expressed in ARC neurones) inhibits feeding and causes weight loss. Conversely, MC4-R antagonists such as ‘agouti’ protein and agouti gene-related peptide (AGRP) stimulate feeding and cause obesity. Ectopic expression of agouti in the hypothalamus leads to obesity in the AVY mouse, while AGRP is co-expressed by NPY neurones in the ARC. Synthetic MC4-R agonists may ultimately find use as anti-obesity drugs in human subjects Orexins-A and -B, derived from prepro-orexin, are expressed in specific neurones of the lateral hypothalamic area (LHA). Orexin-A injected centrally stimulates eating and prepro-orexin mRNA is up regulated by fasting and hypoglycaemia. The LHA is important in receiving sensory signals from the gut and liver, and in sensing glucose, and orexin neurones may be involved in stimulating feeding in response to falls in plasma glucose.
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Denis, R. G. P., C. Bing, S. Brocklehurst, J. A. Harrold, R. G. Vernon e G. Williams. "Diurnal changes in hypothalamic neuropeptide and SOCS-3 expression: effects of lactation and relationship with serum leptin and food intake". Journal of Endocrinology 183, n.º 1 (outubro de 2004): 173–81. http://dx.doi.org/10.1677/joe.1.05659.

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Rats normally eat about 85% of their food at night. Lactation increases food intake 3- to 4-fold, but the diurnal pattern of food intake persists. The mechanisms responsible for the diurnal and lactation-induced changes in food intake are still unresolved, hence we have further investigated the possible roles of serum leptin and hypothalamic expression of neuropeptide Y (NPY), agouti-related peptide (AgRP) and pro-opiomelanocortin (POMC) in rats. Suppressor of cytokine signalling-3 (SOCS-3) acts as a feedback inhibitor of leptin signalling in the hypothalamus, hence changes in expression of SOCS-3 were also investigated. Changes in expression of NPY, AgRP or POMC alone could not account for the diurnal changes in intake and their alteration by lactation. However, there were increased AgRP mRNA:POMC mRNA ratios at night and also during lactation, which were very similar to estimated changes in food intake. Such changes in expression may result in dominance of the orexigenic AgRP peptide over the appetite-suppressing POMC-derived peptides, and so could contribute to the hyperphagia in these states. Diurnal and lactation-related changes in the AgRP mRNA:POMC mRNA ratio and food intake are not due to changes in leptin alone. However, hypoleptinaemia, possibly through increased expression of NPY, may contribute to the hyperphagia of lactation. In the dark, expression of SOCS-3 was decreased in non-lactating rats; lactation decreased SOCS-3 expression in both light and dark phases. However, such changes are likely to enhance the ability of leptin-responsive neurones to transmit the leptin signal, and so are unlikely to contribute to either the nocturnal increase in appetite or the hyperphagia of lactation.
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Joly, A., R. Denis, J. Castel, R. Palmiter, C. Magnan e S. Luquet. "O35 Rôle des Neurones NPY/AgRP dans le contrôle de la balance énergétique". Diabetes & Metabolism 36 (março de 2010): A10. http://dx.doi.org/10.1016/s1262-3636(10)70039-2.

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Joly, A., R. Denis, J. Castel, C. Cansell, C. Magnan e S. Luquet. "035 Implication des neurones NPY/AgRP dans le contrôle de la partition des flux énergétiques en périphérie". Diabetes & Metabolism 37, n.º 1 (março de 2011): A9. http://dx.doi.org/10.1016/s1262-3636(11)70523-7.

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Feng, Bing, Frank Greenway, Jerney Harms, Hesong Liu, Chunmei Wang, Pingwen Xu e Yanlin He. "OR23-3 Hunger Hormone Asprosin Activates Orexigenic Neurons via SK Currents". Journal of the Endocrine Society 6, Supplement_1 (1 de novembro de 2022): A19. http://dx.doi.org/10.1210/jendso/bvac150.039.

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Abstract Neurons that co-express the orexigenic agouti-related protein (AgRP) and neuropeptide Y (NPY) are indispensable for normal feeding behavior. Firing activities of AgRP/NPY neurons dynamically fluctuate with energy status and coordinate appropriate feeding behavior to meet nutritional demands. We previously demonstrated that asprosin, a recently discovered fasting-induced glucogenic and orexigenic hormone, crosses the blood-brain barrier and directly activates the orexigenic AgRP/NPY neurons via a cyclic cAMP-dependent pathway. However, intrinsic mechanisms on how asprosin regulates AgRP/NPY neural activities during the fed-to-fasted transition are not fully understood. In the satiated mice with low circulating levels of asprosin, we found that AgRP/NPY neurons expressed high levels of the small conductance calcium-activated potassium channel 3 (SK3) and were inhibited by SK3-mediated potassium currents. Conversely, in 24 hour-fasting mice with high levels of asprosin, AgRP/NPY neurons expressed low levels of SK3 and were activated via inhibition of SK3-mediated potassium currents. Notably, the stimulatory effects of asprosin on AgRP/NPY neurons were blunted in mice with SK3 selectively deleted in the AgRP/NPY neurons, further supporting a mediating role of SK3. Moreover, we also identified protein tyrosine phosphatase receptor δ (Ptprd), a membrane-bound phosphatase receptor, as the orexigenic asprosin-receptor. Deletion of Ptprd in AgRP/NPY neurons abolished asprosin's stimulatory effect on SK3-mediated currents and protected mice from diet-induced obesity. Lastly, increased circulating levels of asprosin promoted hyperphagia, body weight gain, and glucose intolerance. On the other hand, anti-asprosin antibody treatment decreased food intake and body weight by inhibiting AgRP/NPY and other orexigenic hypothalamic neurons via SK currents stimulation. In summary, our data support a model that asprosin acts on Ptprd expressed by AgRP/NPY neurons to inhibit SK3 current, further activating AgRP/NPY neurons to increase food intake and body weight. Our findings also provided preclinical evidence that asprosin-neutralizing antibodies could be used to treat obesity. Presentation: Monday, June 13, 2022 11:45 a.m. - 12:00 p.m.
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Oh, Youjin, Eun-Seon Yoo, Sang Hyeon Ju, Eunha Kim, Seulgi Lee, Seyun Kim, Kevin Wickman e Jong-Woo Sohn. "GIRK2 potassium channels expressed by the AgRP neurons decrease adiposity and body weight in mice". PLOS Biology 21, n.º 8 (18 de agosto de 2023): e3002252. http://dx.doi.org/10.1371/journal.pbio.3002252.

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It is well known that the neuropeptide Y (NPY)/agouti-related peptide (AgRP) neurons increase appetite and decrease thermogenesis. Previous studies demonstrated that optogenetic and/or chemogenetic manipulations of NPY/AgRP neuronal activity alter food intake and/or energy expenditure (EE). However, little is known about intrinsic molecules regulating NPY/AgRP neuronal excitability to affect long-term metabolic function. Here, we found that the G protein-gated inwardly rectifying K+ (GIRK) channels are key to stabilize NPY/AgRP neurons and that NPY/AgRP neuron-selective deletion of the GIRK2 subunit results in a persistently increased excitability of the NPY/AgRP neurons. Interestingly, increased body weight and adiposity observed in the NPY/AgRP neuron-selective GIRK2 knockout mice were due to decreased sympathetic activity and EE, while food intake remained unchanged. The conditional knockout mice also showed compromised adaptation to coldness. In summary, our study identified GIRK2 as a key determinant of NPY/AgRP neuronal excitability and driver of EE in physiological and stress conditions.
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Goldstone, Anthony P., Unga A. Unmehopa, Stephen R. Bloom e Dick F. Swaab. "Hypothalamic NPY and Agouti-Related Protein Are Increased in Human Illness But Not in Prader-Willi Syndrome and Other Obese Subjects". Journal of Clinical Endocrinology & Metabolism 87, n.º 2 (1 de fevereiro de 2002): 927–37. http://dx.doi.org/10.1210/jcem.87.2.8230.

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Animal studies have demonstrated the importance of orexigenic NPY and agouti-related protein (AGRP) hypothalamic neurons, which are inhibited by the adipocyte hormone leptin, in the regulation of body weight and neuroendocrine secretion. We have examined NPY and AGRP neurons in postmortem human hypothalami from controls, Prader-Willi syndrome and other obese subjects, using quantitative immunocytochemistry (ICC) and in situ hybridization, to identify causes of leptin resistance in human obesity. Using combined ICC and in situ hybridization, AGRP, but not POMC, was colocalized with NPY in infundibular nucleus neurons. Infundibular nucleus (including median eminence) NPY ICC staining or mRNA expression, and AGRP ICC staining, increased with premorbid illness duration. NPY ICC staining and mRNA expression were reduced in obese subjects, but AGRP ICC staining was unchanged, correcting for illness duration. This suggests normal responses of NPY and AGRP neurons to peripheral signals, such as leptin and insulin, in human illness and obesity. The pathophysiology of obesity and illness-associated anorexia appear to lie in downstream or separate neuronal circuits, but the infundibular neurons may mediate neuroendocrine responses to illness. The implications for pharmacological treatment of human obesity are discussed.
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Bugarith, Kishor, Thu T. Dinh, Ai-Jun Li, Robert C. Speth e Sue Ritter. "Basomedial Hypothalamic Injections of Neuropeptide Y Conjugated to Saporin Selectively Disrupt Hypothalamic Controls of Food Intake". Endocrinology 146, n.º 3 (1 de março de 2005): 1179–91. http://dx.doi.org/10.1210/en.2004-1166.

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Neuropeptide Y (NPY) conjugated to saporin (NPY-SAP), a ribosomal inactivating toxin, is a newly developed compound designed to selectively target and lesion NPY receptor-expressing cells. We injected NPY-SAP into the basomedial hypothalamus (BMH), just dorsal to the arcuate nucleus (ARC), to investigate its neurotoxicity and to determine whether ARC NPY neurons are required for glucoprivic feeding. We found that NPY-SAP profoundly reduced NPY Y1 receptor and αMSH immunoreactivity, as well as NPY, Agouti gene-related protein (AGRP), and cocaine and amphetamine-related transcript mRNA expression in the BMH. NPY-SAP lesions were localized to the injection site with no evidence of retrograde transport by hindbrain NPY neurons with BMH terminals. These lesions impaired responses to intracerebroventricular (icv) leptin (5 μg/5 μl·d) and ghrelin (2 μg/5 μl), which are thought to alter feeding primarily by actions on ARC NPY/AGRP and proopiomelanocortin/cocaine and amphetamine-related transcript neurons. However, the hypothesis that NPY/AGRP neurons are required downstream mediators of glucoprivic feeding was not supported. Although NPY/AGRP neurons were destroyed by NPY-SAP, the lesion did not impair either the feeding or the hyperglycemic response to 2-deoxy-d-glucose-induced blockade of glycolysis use. Similarly, responses to glucagon-like peptide-1 (GLP-1, 5 μg/3 μl icv), NPY (5 μg/3 μl icv), cholecystokinin octapeptide (4 μg/kg ip), and β-mercaptoacetate (68 mg/kg ip) were not altered by the NPY-SAP lesion. Thus, NPY-SAP destroyed NPY receptor-expressing neurons in the ARC and selectively disrupted controls of feeding dependent on those neurons but did not disrupt peptidergic or metabolic controls dependent upon circuitry outside the BMH.
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Fraley, G. S., e S. Ritter. "Immunolesion of Norepinephrine and Epinephrine Afferents to Medial Hypothalamus Alters Basal and 2-Deoxy-d-Glucose-Induced Neuropeptide Y and Agouti Gene-Related Protein Messenger Ribonucleic Acid Expression in the Arcuate Nucleus". Endocrinology 144, n.º 1 (1 de janeiro de 2003): 75–83. http://dx.doi.org/10.1210/en.2002-220659.

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Abstract Neuropeptide Y (NPY) and agouti gene-related protein (AGRP) are orexigenic peptides of special importance for control of food intake. In situ hybridization studies have shown that NPY and AGRP mRNAs are increased in the arcuate nucleus of the hypothalamus (ARC) by glucoprivation. Other work has shown that glucoprivation stimulates food intake by activation of hindbrain glucoreceptor cells and requires the participation of rostrally projecting norepinephrine (NE) or epinephrine (E) neurons. Here we determine the role of hindbrain catecholamine afferents in glucoprivation-induced increase in ARC NPY and AGRP gene expression. The selective NE/E immunotoxin saporin-conjugated antidopamineβ-hydroxylase (anti-dβh) was microinjected into the medial hypothalamus and expression of AGRP and NPY mRNA was analyzed subsequently in the ARC under basal and glucoprivic conditions using 33P-labeled in situ hybridization. Saporin-conjugated anti-dβh virtually eliminated dβh-immunoreactive terminals in the ARC without causing nonspecific damage. These lesions significantly increased basal but eliminated 2-deoxy-d-glucose-induced increases in AGRP and NPY mRNA expression. Results indicate that hindbrain catecholaminergic neurons contribute to basal NPY and AGRP gene expression and mediate the responsiveness of NPY and AGRP neurons to glucose deficit. Our results also suggest that catecholamine neurons couple potent orexigenic neural circuitry within the hypothalamus with hindbrain glucose sensors that monitor brain glucose supply.
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Phillips, Colin T., e Richard D. Palmiter. "Role of Agouti-Related Protein-Expressing Neurons in Lactation". Endocrinology 149, n.º 2 (1 de novembro de 2007): 544–50. http://dx.doi.org/10.1210/en.2007-1153.

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Hypothalamic neurons that express agouti-related protein (AgRP) and neuropeptide Y (NPY) are thought to be important for regulation of feeding, especially under conditions of negative energy balance. The expression of NPY and AgRP increases during lactation and may promote the hyperphagia that ensues. We explored the role of AgRP neurons in reproduction and lactation, using a mouse model in which AgRP-expressing neurons were selectively ablated by the action of diphtheria toxin. We show that ablation of AgRP neurons in neonatal mice does not interfere with pregnancy, parturition, or lactation, suggesting that early ablation allows compensatory mechanisms to become established. However, ablation of AgRP neurons after lactation commences results in rapid starvation, indicating that both basal feeding and lactation-induced hyperphagia become dependent on AgRP neurons in adulthood. We also show that constitutive inactivation of Npy and Agrp genes does not prevent pregnancy or lactation, nor does it protect lactating dams from diphtheria toxin-induced starvation.
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Teses / dissertações sobre o assunto "Neurones NPY/AgRP"

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Qu, Mengdi. "Molecular mechanism underlying CaMK1D-dependent function in AgRP neurons". Electronic Thesis or Diss., Strasbourg, 2024. http://www.theses.fr/2024STRAJ029.

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La perturbation des mécanismes de réponse au stress chez les organismes peut entraîner une dysfonction cellulaire et des maladies telles que le syndrome métabolique. L'équilibre énergétique est principalement régulé par le système nerveux central (SNC), qui intègre des signaux hormonaux, neuronaux et alimentaires provenant de divers tissus. Une dysfonction de ce système est liée à l'obésité et au syndrome métabolique, qui sont tous deux des précurseurs du diabète de type 2 (T2D). Notre laboratoire a découvert que la protéine kinase ID dépendante du calcium/calmoduline (CaMK1D), un gène associé au T2D, favorise la prise alimentaire médiée par la ghréline chez les souris. Cependant, le rôle de la signalisation de CaMK1D dans les neurones NPY/AgRP reste encore à éclaircir. Dans cette étude, nous avons réalisé un séquençage de l'ARN en utilisant la lignée cellulaire hypothalamique GT1-7. Nous avons ainsi découvert que CalHM6 est une cible potentielle en aval de la signalisation de CaMK1D. Les niveaux d'ARNm de CalHM6 sont ainsi significativement augmentés dans les cellules CaMK1D-/- et sont réduits lorsque CaMK1D est ré-exprimé. Cela a également été confirmé in vivo dans l'hypothalamus des souris CaMK1D-/-. CalHM6, probablement un canal calcique dépendant du voltage, a montré des niveaux intracellulaires de Ca2+ augmentés en réponse à la ghréline dans les cellules CaMK1D-/- par rapport aux cellules CaMK1D+/+ en utilisant la méthode jGCamps. En résumé, notre travail a montré que CalHM6 est une nouvelle cible de CaMK1D. Une expression élevée de CaMK1D, entraînant une faible expression de CalHM6, pourrait ainsi favoriser la prise alimentaire et l'obésité en modulant la signalisation dépendante du calcium dans les neurones NPY/AgRP
Disruption of stress response mechanisms in organisms can lead to cellular dysfunction and diseases like metabolic syndrome. Energy balance is mainly regulated by the central nervous system (CNS), which integrates hormonal, neuronal, and dietary signals from various tissues. Dysfunction in this system is linked to obesity and metabolic syndrome, both precursors to type 2 diabetes (T2D). Our laboratory discovered that calcium/calmodulin-dependent protein kinase ID (CaMK1D), a gene associated with T2D, promotes ghrelin-mediated food intake in mice. However, CaMK1D signaling in NPY/AgRP neurons still remains questions. In this work, we proformed RNA sequencing using the GT1-7 hypothalamic cell line. To this end, we found that CalHM6 is a downstream target of CaMK1D signaling. CalHM6 mRNA levels were significantly upregulated in CaMK1D-/- cells and downregulated when CaMK1D was re-expressed. This was confirmed in vivo in the hypothalamus of CaMK1D-/- mice. CalHM6, likely a voltage-gated calcium channel, showed increased intracellular Ca2+ levels in response to ghrelin in CaMK1D-/- cells compared to CaMK1D+/+ cells using jGCamps method. Altogether, our work showed CalHM6 is a novel target of CaMK1D. High CaMK1D, leading to low CalHM6 expression, may enhance food intake and obesity by modulating calcium-dependent signaling in NPY/AgRP neuron
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Joly, Aurélie. "Rôle du système nerveux dans le développement du syndrôme métabolique : étude de l'effet du glucose portal sur la sensibilité à l'insuline chez le rat : implication des neurones NPY/AgRP dans le contrôle de la balance énergétique chez la souris". Paris 7, 2011. http://www.theses.fr/2011PA077091.

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Le système nerveux central (SNC) intègre en permanence des signaux périphériques tels que les variations de concentration en hormones et en nutriments, et module en réponse le comportement alimentaire ainsi que la dépense énergétique et le métabolisme. Au niveau du noyau arqué de l'hypothalamus, la barrière hématoencéphalique est plus perméable, ce qui lui confère un rôle de premier ordre dans l'intégration des signaux périphériques. Les neurones du noyau arqué de l'hypothalamus qui sécrètent le neuropeptide Y et l'Agouti Related Protein (NPY/AgRP) sont impliqués dans la stimulation de la prise alimentaire et la diminution de la dépense énergétique. Contrairement aux résultats attendus, l'ablation de ces neurones oréxigènes au stade néonatal chez la souris conduit au développement d'une obésité massive à l'âge adulte. Cette obésité se développe sans hyperphagie, et les analyses métaboliques montrent que les animaux ont une dépense énergétique similaire aux témoins. Les souris déficientes ne sont pas diabétiques contrairement à d'autres modèles d'obésité, mais sont caractérisées par une hyperinsulinémie basale associé à une altération du métabolisme lipidique. Nous montrons que la perte de ces neurones induit une modulation du renouvellement des catécholamines qui se traduit en périphérie par une redistribution des flux métaboliques, favorisant le métabolisme lipidique. Cette redistribution serait responsable du développement de l'obésité en favorisant les mécanismes de stockage, mais permettrait de limiter les effets d'un régime gras sur l'homéostasie glucidique
Several neuronal populations are involved in the regulation of energy balance. Among these, the hypothalamic agouti-related protein neurons (AgRP-neurons) are well characterized for their ability to promote food intake. Using cell-specific ablation we investigated a possible role of AgRP neurons in nutrient partitioning independent from food intake. We show that mice lacking AgRP neuron developed a non-hyperphagic obesity due to increased feed efficiency (weight gain/kcal consumed) on regular chow. At a time that preceded obesity catecholamine turnover rate was selectively decreased in the pancreas, liver, and glycolytic muscle, while it was increased in oxidative muscle. Respiratory quotient measurements revealed a change in substrate utilization towards lipid oxidation enhanced by synergistic increase in liver triglyceride synthesis and lipid substrate preference in oxidative muscle mitochondria. On high fat diet, mice lacking AgRP neurons displayed reduced body weight gain and paradoxical improvement in glucose tolerance. Finally we evidenced that Gamma Aminobutyric Acid (GABA) made by AgRP neurons is important in the central control of peripheral substrate utilization. This study reveals a new function for AgRP neurons in the coordination, via the sympathetic nervous System, of inter-organs communication and nutrient partitioning. These results offer a new conceptual framework for the understanding of obesity-related disorders
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Livros sobre o assunto "Neurones NPY/AgRP"

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Wójcik-Gładysz, Anna. Ghrelin – hormone with many faces. Central regulation and therapy. The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, 2020. http://dx.doi.org/10.22358/mono_awg_2020.

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Discovered in 1999, ghrelin, is one of the peptides co-creating the hypothalamicgastrointestinal axis, otherwise known as the brain-gut axis. Ghrelin participates in many physiological processes and spectrum of its activity is still being discovered. This 28 amino acid peptide ‒ a product of the ghrl gene, was found in all vertebrates and is synthesized and secreted mainly from enteroendocrine X/A cells located in the gastric mucosa of the stomach. Expression of the ghrelin receptor has been found in many nuclei of the hypothalamus involved in appetite regulation. Therefore it’s presumed that ghrelin is one of the crucial hormones deciphering the energy status required for the maintenance of organism homeostasis. Ghrelin acts as a signal of starvation or energy insufficiency and its level in plasma is reduced after the meal. Neuropeptide Y (NPY) and agouti-related peptide (AgRP; NPY/AgRP) neurons located in the arcuate nucleus (ARC) area are the main target of ghrelin in the hypothalamus. This subpopulation of neurons is indispensable for inducing orexigenic action of ghrelin. Moreover ghrelin acting as a neurohormone, mainly in the hypothalamus area, plays an important role in the regulation of growth and reproduction processes. Indeed, ghrelin action on reproductive processes has been observed in the systemic effects exerted at both hypothalamus-pituitary and gonadal levels. Similarly the GH-releasing ghrelin action was observed both on the hypothalamus level and directly on the somatotrophic cells in the pituitary and this dose-related GH releasing activity was found in in vitro as well as in in vivo experiments. In recent years, numerous studies revealed that ghrelin potentially takes part in the treatment of diseases associated with serious disturbances in the organism energy balance and/or functioning of the gastrointestinal tract. It was underlined that ghrelin may be a hormone with a broad spectrum of therapeutic effect on obesity and anorexia nervosa, as well as may also have protective effect on neurodegenerative diseases, inflammatory disorders or functional changes in the body caused by cancers. In overall, ghrelin treatment has been tested in over 100 preclinical studies with healthy volunteers as well as patients with various types of cancer, eating disorders such as anorexia nervosa and bulimia nervosa. It was observed that ghrelin has an excellent clinical safety profile and emerging side effects occurred only in 3–10% of patients and did not constitute a sufficient premise to discontinue the therapy. In general, it can be concluded that ghrelin may be sufficiently used as a prescription drug.
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