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1.
Cell ; 175(3): 665-678.e23, 2018 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-30245012

RESUMO

The gut is now recognized as a major regulator of motivational and emotional states. However, the relevant gut-brain neuronal circuitry remains unknown. We show that optical activation of gut-innervating vagal sensory neurons recapitulates the hallmark effects of stimulating brain reward neurons. Specifically, right, but not left, vagal sensory ganglion activation sustained self-stimulation behavior, conditioned both flavor and place preferences, and induced dopamine release from Substantia nigra. Cell-specific transneuronal tracing revealed asymmetric ascending pathways of vagal origin throughout the CNS. In particular, transneuronal labeling identified the glutamatergic neurons of the dorsolateral parabrachial region as the obligatory relay linking the right vagal sensory ganglion to dopamine cells in Substantia nigra. Consistently, optical activation of parabrachio-nigral projections replicated the rewarding effects of right vagus excitation. Our findings establish the vagal gut-to-brain axis as an integral component of the neuronal reward pathway. They also suggest novel vagal stimulation approaches to affective disorders.


Assuntos
Intestinos/fisiologia , Recompensa , Substância Negra/fisiologia , Nervo Vago/fisiologia , Vias Aferentes/metabolismo , Vias Aferentes/fisiologia , Animais , Dopamina/metabolismo , Neurônios Dopaminérgicos/fisiologia , Ácido Glutâmico/metabolismo , Intestinos/inervação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Optogenética
2.
Cell ; 155(1): 228-41, 2013 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-24074871

RESUMO

The powerful regulation of bone mass exerted by the brain suggests the existence of bone-derived signals modulating this regulation or other functions of the brain. We show here that the osteoblast-derived hormone osteocalcin crosses the blood-brain barrier, binds to neurons of the brainstem, midbrain, and hippocampus, enhances the synthesis of monoamine neurotransmitters, inhibits GABA synthesis, prevents anxiety and depression, and favors learning and memory independently of its metabolic functions. In addition to these postnatal functions, maternal osteocalcin crosses the placenta during pregnancy and prevents neuronal apoptosis before embryos synthesize this hormone. As a result, the severity of the neuroanatomical defects and learning and memory deficits of Osteocalcin(-/-) mice is determined by the maternal genotype, and delivering osteocalcin to pregnant Osteocalcin(-/-) mothers rescues these abnormalities in their Osteocalcin(-/-) progeny. This study reveals that the skeleton via osteocalcin influences cognition and contributes to the maternal influence on fetal brain development.


Assuntos
Encéfalo/crescimento & desenvolvimento , Osteocalcina/metabolismo , Transdução de Sinais , Envelhecimento , Animais , Encéfalo/embriologia , Encéfalo/fisiologia , Feminino , Feto/metabolismo , Camundongos , Neurotransmissores/metabolismo , Gravidez
4.
Proc Natl Acad Sci U S A ; 120(16): e2300015120, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37036983

RESUMO

Anorexia nervosa (AN) is a psychiatric illness with the highest mortality. Current treatment options have been limited to psychotherapy and nutritional support, with low efficacy and high relapse rates. Hypothalamic AgRP (agouti-related peptide) neurons that coexpress AGRP and neuropeptide Y (NPY) play a critical role in driving feeding while also modulating other complex behaviors. We have previously reported that genetic ablation of Tet3, which encodes a member of the TET family dioxygenases, specifically in AgRP neurons in mice, activates these neurons and increases the expression of AGRP, NPY, and the vesicular GABA transporter (VGAT), leading to hyperphagia and anxiolytic effects. Bobcat339 is a synthetic small molecule predicted to bind to the catalytic pockets of TET proteins. Here, we report that Bobcat339 is effective in mitigating AN and anxiety/depressive-like behaviors using a well-established mouse model of activity-based anorexia (ABA). We show that treating mice with Bobcat339 decreases TET3 expression in AgRP neurons and activates these neurons leading to increased feeding, decreased compulsive running, and diminished lethality in the ABA model. Mechanistically, Bobcat339 induces TET3 protein degradation while simultaneously stimulating the expression of AGRP, NPY, and VGAT in a TET3-dependent manner both in mouse and human neuronal cells, demonstrating a conserved, previously unsuspected mode of action of Bobcat339. Our findings suggest that Bobcat339 may potentially be a therapeutic for anorexia nervosa and stress-related disorders.


Assuntos
Anorexia Nervosa , Dioxigenases , Camundongos , Humanos , Animais , Proteína Relacionada com Agouti/genética , Proteína Relacionada com Agouti/metabolismo , Anorexia Nervosa/tratamento farmacológico , Anorexia Nervosa/metabolismo , Neurônios/metabolismo , Hipotálamo/metabolismo , Modelos Animais , Dioxigenases/metabolismo
5.
Cell ; 138(5): 976-89, 2009 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-19737523

RESUMO

Leptin inhibition of bone mass accrual requires the integrity of specific hypothalamic neurons but not expression of its receptor on these neurons. The same is true for its regulation of appetite and energy expenditure. This suggests that leptin acts elsewhere in the brain to achieve these three functions. We show here that brainstem-derived serotonin (BDS) favors bone mass accrual following its binding to Htr2c receptors on ventromedial hypothalamic neurons and appetite via Htr1a and 2b receptors on arcuate neurons. Leptin inhibits these functions and increases energy expenditure because it reduces serotonin synthesis and firing of serotonergic neurons. Accordingly, while abrogating BDS synthesis corrects the bone, appetite and energy expenditure phenotypes caused by leptin deficiency, inactivation of the leptin receptor in serotonergic neurons recapitulates them fully. This study modifies the map of leptin signaling in the brain and identifies a molecular basis for the common regulation of bone and energy metabolisms. For a video summary of this article, see the PaperFlick file with the Supplemental Data available online.


Assuntos
Apetite , Densidade Óssea , Metabolismo Energético , Leptina/metabolismo , Serotonina/metabolismo , Tronco Encefálico/metabolismo , Hipotálamo/metabolismo , Receptores para Leptina/metabolismo , Transdução de Sinais
6.
Mol Psychiatry ; 27(10): 3951-3960, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35906488

RESUMO

Hypothalamic agouti-related peptide and neuropeptide Y-expressing (AgRP) neurons have a critical role in both feeding and non-feeding behaviors of newborn, adolescent, and adult mice, suggesting their broad modulatory impact on brain functions. Here we show that constitutive impairment of AgRP neurons or their peripubertal chemogenetic inhibition resulted in both a numerical and functional reduction of neurons in the medial prefrontal cortex (mPFC) of mice. These changes were accompanied by alteration of oscillatory network activity in mPFC, impaired sensorimotor gating, and altered ambulatory behavior that could be reversed by the administration of clozapine, a non-selective dopamine receptor antagonist. The observed AgRP effects are transduced to mPFC in part via dopaminergic neurons in the ventral tegmental area and may also be conveyed by medial thalamic neurons. Our results unmasked a previously unsuspected role for hypothalamic AgRP neurons in control of neuronal pathways that regulate higher-order brain functions during development and in adulthood.


Assuntos
Hipotálamo , Neuropeptídeo Y , Animais , Camundongos , Proteína Relacionada com Agouti/metabolismo , Neurônios Dopaminérgicos/metabolismo , Hipotálamo/metabolismo , Neuropeptídeo Y/metabolismo , Córtex Pré-Frontal/metabolismo
7.
BMC Biol ; 20(1): 93, 2022 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-35491423

RESUMO

BACKGROUND: Estriol (E3) is a steroid hormone formed only during pregnancy in primates including humans. Although E3 is synthesized at large amounts through a complex pathway involving the fetus and placenta, it is not required for the maintenance of pregnancy and has classically been considered virtually inactive due to associated very weak canonical estrogen signaling. However, estrogen exposure during pregnancy may have an effect on organs both within and outside the reproductive system, and compounds with binding affinity for estrogen receptors weaker than E3 have been found to impact reproductive organs and the brain. Here, we explore potential effects of E3 on fetal development using mouse as a model system. RESULTS: We administered E3 to pregnant mice, exposing the fetus to E3. Adult females exposed to E3 in utero (E3-mice) had increased fertility and superior pregnancy outcomes. Female and male E3-mice showed decreased anxiety and increased exploratory behavior. The expression levels and DNA methylation patterns of multiple genes in the uteri and brains of E3-mice were distinct from controls. E3 promoted complexing of estrogen receptors with several DNA/histone modifiers and their binding to target genes. E3 functions by driving epigenetic change, mediated through epigenetic modifier interactions with estrogen receptors rather than through canonical nuclear transcriptional activation. CONCLUSIONS: We identify an unexpected functional role for E3 in fetal reproductive system and brain. We further identify a novel mechanism of estrogen action, through recruitment of epigenetic modifiers to estrogen receptors and their target genes, which is not correlated with the traditional view of estrogen potency.


Assuntos
Estrogênios , Receptores de Estrogênio , Animais , Encéfalo/metabolismo , Epigênese Genética , Estriol , Estrogênios/genética , Estrogênios/metabolismo , Feminino , Feto/metabolismo , Masculino , Camundongos , Gravidez , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Esteroides
8.
Annu Rev Neurosci ; 37: 101-16, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24821311

RESUMO

The basic elements of animal behavior that are critical to survival include energy, arousal, and motivation: Energy intake and expenditure are fundamental to all organisms for the performance of any type of function; according to the Yerkes-Dodson law, an optimal level of arousal is required for animals to perform normal functions; and motivation is critical to goal-oriented behaviors in higher animals. The brain is the primary organ that controls these elements and, through evolution, has developed specialized structures to accomplish this task. The orexin/hypocretin system in the perifornical/lateral hypothalamus, which was discovered 15 years ago, is one such specialized area. This review summarizes a fast-growing body of evidence discerning how the orexin/hypocretin system integrates internal and external cues to regulate energy intake that can then be used to generate sufficient arousal for animals to perform innate and goal-oriented behaviors.


Assuntos
Nível de Alerta/fisiologia , Metabolismo Energético/fisiologia , Região Hipotalâmica Lateral/fisiologia , Região Hipotalâmica Lateral/fisiopatologia , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Motivação/fisiologia , Narcolepsia/fisiopatologia , Neuropeptídeos/fisiologia , Animais , Humanos , Orexinas
9.
Mol Psychiatry ; 26(7): 2740-2752, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33879866

RESUMO

Microglia have been implicated in synapse remodeling by phagocytosis of synaptic elements in the adult brain, but the mechanisms involved in the regulation of this process are ill-defined. By examining microglia-neuronal interaction in the ventral hippocampus, we found a significant reduction in spine synapse number during the light phase of the light/dark cycle accompanied by increased microglia-synapse contacts and an elevated amount of microglial phagocytic inclusions. This was followed by a transient rise in microglial production of reactive oxygen species (ROS) and a concurrent increase in expression of uncoupling protein 2 (Ucp2), a regulator of mitochondrial ROS generation. Conditional ablation of Ucp2 from microglia hindered phasic elimination of spine synapses with consequent accumulations of ROS and lysosome-lipid droplet complexes, which resulted in hippocampal neuronal circuit dysfunctions assessed by electrophysiology, and altered anxiety-like behavior. These observations unmasked a novel and chronotypical interaction between microglia and neurons involved in the control of brain functions.


Assuntos
Ansiedade , Hipocampo , Microglia , Neurônios , Proteína Desacopladora 2/genética , Animais , Feminino , Masculino , Camundongos , Camundongos Knockout , Vias Neurais , Sinapses
10.
Nature ; 519(7541): 45-50, 2015 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-25707796

RESUMO

Hypothalamic pro-opiomelanocortin (POMC) neurons promote satiety. Cannabinoid receptor 1 (CB1R) is critical for the central regulation of food intake. Here we test whether CB1R-controlled feeding in sated mice is paralleled by decreased activity of POMC neurons. We show that chemical promotion of CB1R activity increases feeding, and notably, CB1R activation also promotes neuronal activity of POMC cells. This paradoxical increase in POMC activity was crucial for CB1R-induced feeding, because designer-receptors-exclusively-activated-by-designer-drugs (DREADD)-mediated inhibition of POMC neurons diminishes, whereas DREADD-mediated activation of POMC neurons enhances CB1R-driven feeding. The Pomc gene encodes both the anorexigenic peptide α-melanocyte-stimulating hormone, and the opioid peptide ß-endorphin. CB1R activation selectively increases ß-endorphin but not α-melanocyte-stimulating hormone release in the hypothalamus, and systemic or hypothalamic administration of the opioid receptor antagonist naloxone blocks acute CB1R-induced feeding. These processes involve mitochondrial adaptations that, when blocked, abolish CB1R-induced cellular responses and feeding. Together, these results uncover a previously unsuspected role of POMC neurons in the promotion of feeding by cannabinoids.


Assuntos
Canabinoides/farmacologia , Ingestão de Alimentos/efeitos dos fármacos , Ingestão de Alimentos/fisiologia , Hipotálamo/citologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Pró-Opiomelanocortina/metabolismo , Animais , Metabolismo Energético/efeitos dos fármacos , Hipotálamo/efeitos dos fármacos , Hipotálamo/fisiologia , Canais Iônicos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Naloxona/farmacologia , Receptor CB1 de Canabinoide/agonistas , Receptor CB1 de Canabinoide/metabolismo , Resposta de Saciedade/efeitos dos fármacos , Resposta de Saciedade/fisiologia , Proteína Desacopladora 2 , alfa-MSH/metabolismo , beta-Endorfina/metabolismo
11.
J Cell Mol Med ; 23(4): 0, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30734494

RESUMO

Tumour necrotic factor receptor-2 (TNFR2) has been to be cardiac-protective and is expressed in cardiac progenitor cells. Our goal is to define the mechanism for TNFR2-mediated cardiac stem cell activation and differentiation. By employing a protocol of in vitro cardiac stem cell (CSC) differentiation from human inducible pluripotent stem cell (hiPSC), we show that expression of TNFR2 precedes expression of CSC markers followed by expression of mature cardiomyocyte proteins. Activation of TNFR2 by a specific agonist promotes whereas inhibition of TNFR2 by neutralizing antibody diminishes hiPSC-based CSC differentiation. Interestingly, pluripotent cell factor RNA-binding protein Lin28 enhances TNFR2 protein expression in early CSC activation by directly binding to a conserved Lin28-motif within the 3'UTR of Tnfr2 mRNA. Furthermore, inhibition of Lin28 blunts TNFR2 expression and TNFR2-dependent CSC activation and differentiation. Our study demonstrates a critical role of Lin28-TNFR2 axis in CSC activation and survival, providing a novel strategy to enhance stem cell-based therapy for the ischaemic heart diseases.


Assuntos
Diferenciação Celular , Células-Tronco Embrionárias Humanas/citologia , Células-Tronco Pluripotentes Induzidas/citologia , Miócitos Cardíacos/citologia , Proteínas de Ligação a RNA/metabolismo , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , Células Cultivadas , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Miócitos Cardíacos/metabolismo , Transdução de Sinais
12.
Biol Reprod ; 99(2): 349-359, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29425272

RESUMO

Endometriosis is an estrogen-dependent inflammatory disorder among reproductive-aged women associated with pelvic pain, anxiety, and depression. Pain is characterized by central sensitization; however, it is not clear if endometriosis leads to increased pain perception or if women with the disease are more sensitive to pain, increasing the detection of endometriosis. Endometriosis was induced in mice and changes in behavior including pain perception, brain electrophysiology, and gene expression were characterized. Behavioral tests revealed that mice with endometriosis were more depressed, anxious and sensitive to pain compared to sham controls. Microarray analyses confirmed by qPCR identified differential gene expression in several regions of brain in mice with endometriosis. In these mice, genes such as Gpr88, Glra3 in insula, Chrnb4, Npas4 in the hippocampus, and Lcn2 in the amygdala were upregulated while Lct, Serpina3n (insula), and Nptx2 (amygdala) were downregulated. These genes are involved in anxiety, locomotion, and pain. Patch clamp recordings in the amygdala were altered in endometriosis mice demonstrating an effect of endometriosis on brain electrophysiology. Endometriosis induced pain sensitization, anxiety, and depression by modulating brain gene expression and electrophysiology; the effect of endometriosis on the brain may underlie pain sensitization and mood disorders reported in women with the disease.


Assuntos
Ansiedade/fisiopatologia , Comportamento Animal/fisiologia , Encéfalo/fisiopatologia , Depressão/fisiopatologia , Endometriose/fisiopatologia , Expressão Gênica , Limiar da Dor/fisiologia , Animais , Ansiedade/etiologia , Depressão/etiologia , Fenômenos Eletrofisiológicos , Endometriose/complicações , Endometriose/genética , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Atividade Motora/fisiologia
13.
Nat Med ; 13(1): 89-94, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17195839

RESUMO

Metabolic hormones, such as leptin, alter the input organization of hypothalamic circuits, resulting in increased pro-opiomelanocortin (POMC) tone, followed by decreased food intake and adiposity. The gonadal steroid estradiol can also reduce appetite and adiposity, and it influences synaptic plasticity. Here we report that estradiol (E2) triggers a robust increase in the number of excitatory inputs to POMC neurons in the arcuate nucleus of wild-type rats and mice. This rearrangement of synapses in the arcuate nucleus is leptin independent because it also occurred in leptin-deficient (ob/ob) and leptin receptor-deficient (db/db) mice, and was paralleled by decreased food intake and body weight gain as well as increased energy expenditure. However, estrogen-induced decrease in body weight was dependent on Stat3 activation in the brain. These observations support the notion that synaptic plasticity of arcuate nucleus feeding circuits is an inherent element in body weight regulation and offer alternative approaches to reducing adiposity under conditions of failed leptin receptor signaling.


Assuntos
Estradiol/farmacologia , Melanocortinas/metabolismo , Neurônios/efeitos dos fármacos , Obesidade/fisiopatologia , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Anorexia/induzido quimicamente , Anorexia/fisiopatologia , Núcleo Arqueado do Hipotálamo/citologia , Núcleo Arqueado do Hipotálamo/fisiologia , Núcleo Arqueado do Hipotálamo/ultraestrutura , Peso Corporal/efeitos dos fármacos , Estradiol/administração & dosagem , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/fisiologia , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Feminino , Injeções Intraventriculares , Leptina/genética , Leptina/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Obesos , Microscopia Eletrônica , Neurônios/citologia , Neurônios/metabolismo , Obesidade/genética , Ovariectomia , Pró-Opiomelanocortina/metabolismo , Ratos , Ratos Sprague-Dawley
14.
Nature ; 454(7206): 846-51, 2008 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-18668043

RESUMO

The gut-derived hormone ghrelin exerts its effect on the brain by regulating neuronal activity. Ghrelin-induced feeding behaviour is controlled by arcuate nucleus neurons that co-express neuropeptide Y and agouti-related protein (NPY/AgRP neurons). However, the intracellular mechanisms triggered by ghrelin to alter NPY/AgRP neuronal activity are poorly understood. Here we show that ghrelin initiates robust changes in hypothalamic mitochondrial respiration in mice that are dependent on uncoupling protein 2 (UCP2). Activation of this mitochondrial mechanism is critical for ghrelin-induced mitochondrial proliferation and electric activation of NPY/AgRP neurons, for ghrelin-triggered synaptic plasticity of pro-opiomelanocortin-expressing neurons, and for ghrelin-induced food intake. The UCP2-dependent action of ghrelin on NPY/AgRP neurons is driven by a hypothalamic fatty acid oxidation pathway involving AMPK, CPT1 and free radicals that are scavenged by UCP2. These results reveal a signalling modality connecting mitochondria-mediated effects of G-protein-coupled receptors on neuronal function and associated behaviour.


Assuntos
Proteína Relacionada com Agouti/metabolismo , Grelina/metabolismo , Canais Iônicos/metabolismo , Proteínas Mitocondriais/metabolismo , Neurônios/metabolismo , Neuropeptídeo Y/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteína Relacionada com Agouti/genética , Animais , Carnitina O-Palmitoiltransferase/metabolismo , Ácidos Graxos/metabolismo , Comportamento Alimentar/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Grelina/farmacologia , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Canais Iônicos/genética , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Potencial da Membrana Mitocondrial/fisiologia , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/fisiologia , Proteínas Mitocondriais/genética , Neurônios/efeitos dos fármacos , Neuropeptídeo Y/genética , Fosforilação/efeitos dos fármacos , Sinapses/efeitos dos fármacos , Sinapses/metabolismo , Proteína Desacopladora 2
15.
Cereb Cortex ; 23(8): 2007-14, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22767632

RESUMO

Prolyl endopeptidase (PREP) is a phylogenetically conserved serine protease and, in humans and rodents, is highly expressed in the brain. Several neuropeptides associated with learning and memory and neurodegenerative disorders have been proposed to be the substrates for PREP, suggesting a possible role for PREP in these processes. However, its physiological function remains elusive. Combining genetic, anatomical, electrophysiological, and behavioral approaches, we show that PREP genetrap mice have decreased synaptic spine density in the CA1 region of the hippocampus, reduced hippocampal long-term potentiation, impaired hippocampal-mediated learning and memory, and reduced growth-associated protein-43 levels when compared with wild-type controls. These observations reveal a role for PREP in mediating hippocampal plasticity and spatial memory formation, with implications for its pharmacological manipulation in diseases related to cognitive impairment.


Assuntos
Região CA1 Hipocampal/ultraestrutura , Espinhas Dendríticas/ultraestrutura , Potenciação de Longa Duração/fisiologia , Aprendizagem em Labirinto/fisiologia , Memória/fisiologia , Serina Endopeptidases/fisiologia , Sinapses/ultraestrutura , Animais , Região CA1 Hipocampal/fisiologia , Técnicas de Silenciamento de Genes , Masculino , Camundongos , Prolil Oligopeptidases , Serina Endopeptidases/genética
16.
Science ; 385(6707): 409-416, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39052814

RESUMO

Understanding the neural basis of infant social behaviors is crucial for elucidating the mechanisms of early social and emotional development. In this work, we report a specific population of somatostatin-expressing neurons in the zona incerta (ZISST) of preweaning mice that responds dynamically to social interactions, particularly those with their mother. Bidirectional neural activity manipulations in pups revealed that widespread connectivity of preweaning ZISST neurons to sensory, emotional, and cognitive brain centers mediates two key adaptive functions associated with maternal presence: the reduction of behavior distress and the facilitation of learning. These findings reveal a population of neurons in the infant mouse brain that coordinate the positive effects of the relationship with the mother on an infant's behavior and physiology.


Assuntos
Neurônios , Comportamento Social , Interação Social , Somatostatina , Zona Incerta , Animais , Feminino , Masculino , Camundongos , Emoções , Aprendizagem , Comportamento Materno , Neurônios/metabolismo , Neurônios/fisiologia , Somatostatina/metabolismo , Zona Incerta/metabolismo , Zona Incerta/fisiologia
17.
J Physiol ; 591(7): 1951-66, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23318871

RESUMO

Hypocretin (orexin), a neuropeptide synthesized exclusively in the perifornical/lateral hypothalamus, is critical for drug seeking and relapse, but it is not clear how the circuitry centred on hypocretin-producing neurons (hypocretin neurons) is modified by drugs of abuse and how changes in this circuit might alter behaviours related to drug addiction. In this study, we show that repeated, but not single, in vivo cocaine administration leads to a long-lasting, experience-dependent potentiation of glutamatergic synapses on hypocretin neurons in mice following a cocaine-conditioned place preference (CPP) protocol. The synaptic potentiation occurs postsynaptically and probably involves up-regulation of AMPA-type glutamate receptors on hypocretin neurons. Phosphorylation of cAMP response element-binding protein (CREB) is also significantly increased in hypocretin neurons in cocaine-treated animals, suggesting that CREB-mediated pathways may contribute to synaptic potentiation in these cells. Furthermore, the potentiation of synaptic efficacy in hypocretin neurons persists during cocaine withdrawal, but reverses to baseline levels after prolonged abstinence. Finally, the induction of long-term potentiation (LTP) triggered by a high-frequency stimulation is facilitated in hypocretin neurons in cocaine-treated mice, suggesting that long-lasting changes in synapses onto hypocretin neurons would probably be further potentiated by other stimuli (such as concurrent environmental cues) paired with the drug. In summary, we show here that hypocretin neurons undergo experience-dependent synaptic potentiation that is distinct from that reported in other reward systems, such as the ventral tegmental area, following exposure to cocaine. These findings support the idea that the hypocretin system is important for behavioural changes associated with cocaine administration in animals and humans.


Assuntos
Cocaína/administração & dosagem , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Neurônios/efeitos dos fármacos , Neuropeptídeos/fisiologia , Sinapses/efeitos dos fármacos , Animais , Condicionamento Psicológico , Potenciais Pós-Sinápticos Excitadores , Hipotálamo/fisiologia , Potenciação de Longa Duração , Camundongos , Camundongos Endogâmicos C57BL , Plasticidade Neuronal/efeitos dos fármacos , Neurônios/fisiologia , Orexinas , Sinapses/fisiologia
18.
Cell Metab ; 5(1): 21-33, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17189204

RESUMO

The active thyroid hormone, triiodothyronine (T3), regulates mitochondrial uncoupling protein activity and related thermogenesis in peripheral tissues. Type 2 deiodinase (DII), an enzyme that catalyzes active thyroid hormone production, and mitochondrial uncoupling protein 2 (UCP2) are also present in the hypothalamic arcuate nucleus, where their interaction and physiological significance have not been explored. Here, we report that DII-producing glial cells are in direct apposition to neurons coexpressing neuropeptide Y (NPY), agouti-related protein (AgRP), and UCP2. Fasting increased DII activity and local thyroid hormone production in the arcuate nucleus in parallel with increased GDP-regulated UCP2-dependent mitochondrial uncoupling. Fasting-induced T3-mediated UCP2 activation resulted in mitochondrial proliferation in NPY/AgRP neurons, an event that was critical for increased excitability of these orexigenic neurons and consequent rebound feeding following food deprivation. These results reveal a physiological role for a thyroid-hormone-regulated mitochondrial uncoupling in hypothalamic neuronal networks.


Assuntos
Núcleo Arqueado do Hipotálamo/metabolismo , Jejum , Comportamento Alimentar , Canais Iônicos/metabolismo , Proteínas Mitocondriais/metabolismo , Neurônios/metabolismo , Termogênese , Tri-Iodotironina/metabolismo , Proteína Relacionada com Agouti , Animais , Núcleo Arqueado do Hipotálamo/citologia , Ingestão de Alimentos , Proteínas de Fluorescência Verde , Guanosina Difosfato/metabolismo , Hipotálamo/citologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Iodeto Peroxidase/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/metabolismo , Neuroglia/metabolismo , Neuropeptídeo Y/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Proteína Desacopladora 2 , Iodotironina Desiodinase Tipo II
19.
Endocr Rev ; 43(4): 743-760, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34792130

RESUMO

The hypocretin/orexin (Hcrt/Orx) system in the perifornical lateral hypothalamus has been recognized as a critical node in a complex network of neuronal systems controlling both physiology and behavior in vertebrates. Our understanding of the Hcrt/Orx system and its array of functions and actions has grown exponentially in merely 2 decades. This review will examine the latest progress in discerning the roles played by the Hcrt/Orx system in regulating homeostatic functions and in executing instinctive and learned behaviors. Furthermore, the gaps that currently exist in our knowledge of sex-related differences in this field of study are discussed.


Assuntos
Neuropeptídeos , Animais , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Neurônios/fisiologia , Neuropeptídeos/fisiologia , Orexinas
20.
Reprod Sci ; 29(1): 243-249, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34279849

RESUMO

Endometriosis is a gynecological disease affecting 6-10% of women of reproductive age. In addition to gynecologic symptoms, endometriosis is associated with various systemic effects, including inflammation, altered body weight, and behavioral changes. Previous murine studies demonstrate that endometriosis is causally inked to increased pain sensitization, behavioral changes, and low body mass index (BMI). One possible cellular target that may mediate some of these findings is the hypocretin/orexin neurons. This neuronal system plays a role in regulating wakefulness/sleep cycles, pain perception, and appetite. We hypothesize that endometriosis alters activity level of the hypocretin/orexin (Hcrt) neuronal system. Mice underwent endometriosis induction surgeries (endo) or sham surgeries (sham) for the development of the experimental model. Immunocytochemistry was performed on harvested samples from the lateral hypothalamus, and activation levels of Hcrt cells were examined by quantifying the expression of phosphorylation of cAMP-responsive element binding protein (CREB) in these cells after an acute stress in sham and endo mice. Mice with endometriosis had greater Hcrt neurons activation than sham mice. Mice with endometriosis fed with high fat diet showed a lower fat/body weight and fat/lean tissue ratio compared to mice without endometriosis. There was no significant difference in food intake between sham and endometriosis mice. These results demonstrate that endometriosis is associated with low body mass and increased hypocretin/orexin activity, which could be implicated in the behavioral changes and to differences in body composition.


Assuntos
Endometriose/metabolismo , Região Hipotalâmica Lateral/metabolismo , Neurônios/metabolismo , Orexinas/metabolismo , Animais , Peso Corporal/fisiologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Dieta Hiperlipídica , Modelos Animais de Doenças , Feminino , Camundongos
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