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1.
Brain Behav Immun ; 121: 122-141, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38986725

RESUMO

Multiple system atrophy (MSA) is a severe α-synucleinopathy facilitated by glial reactions; the cerebellar variant (MSA-C) preferentially involves olivopontocerebellar fibres with conspicuous demyelination. A lack of aggressive models that preferentially involve olivopontocerebellar tracts in adulthood has hindered our understanding of the mechanisms of demyelination and neuroaxonal loss, and thus the development of effective treatments for MSA. We therefore aimed to develop a rapidly progressive mouse model that recaptures MSA-C pathology. We crossed Plp1-tTA and tetO-SNCA*A53T mice to generate Plp1-tTA::tetO-SNCA*A53T bi-transgenic mice, in which human A53T α-synuclein-a mutant protein with enhanced aggregability-was specifically produced in the oligodendrocytes of adult mice using Tet-Off regulation. These bi-transgenic mice expressed mutant α-synuclein from 8 weeks of age, when doxycycline was removed from the diet. All bi-transgenic mice presented rapidly progressive motor deterioration, with wide-based ataxic gait around 22 weeks of age and death around 30 weeks of age. They also had prominent demyelination in the brainstem/cerebellum. Double immunostaining demonstrated that myelin basic protein was markedly decreased in areas in which SM132, an axonal marker, was relatively preserved. Demyelinating lesions exhibited marked ionised calcium-binding adaptor molecule 1-, arginase-1-, and toll-like receptor 2-positive microglial reactivity and glial fibrillary acidic protein-positive astrocytic reactivity. Microarray analysis revealed a strong inflammatory response and cytokine/chemokine production in bi-transgenic mice. Neuronal nuclei-positive neuronal loss and patchy microtubule-associated protein 2-positive dendritic loss became prominent at 30 weeks of age. However, a perceived decrease in tyrosine hydroxylase-positive neurons in the substantia nigra pars compacta in bi-transgenic mice compared with wild-type mice was not significant, even at 30 weeks of age. Wild-type, Plp1-tTA, and tetO-SNCA*A53T mice developed neither motor deficits nor demyelination. In bi-transgenic mice, double immunostaining revealed human α-synuclein accumulation in neurite outgrowth inhibitor A (Nogo-A)-positive oligodendrocytes beginning at 9 weeks of age; its expression was further increased at 10 to 12 weeks, and these increased levels were maintained at 12, 24, and 30 weeks. In an α-synuclein-proximity ligation assay, α-synuclein oligomers first appeared in brainstem oligodendrocytes as early as 9 weeks of age; they then spread to astrocytes, neuropil, and neurons at 12 and 16 weeks of age. α-Synuclein oligomers in the brainstem neuropil were most abundant at 16 weeks of age and decreased thereafter; however, those in Purkinje cells successively increased until 30 weeks of age. Double immunostaining revealed the presence of phosphorylated α-synuclein in Nogo-A-positive oligodendrocytes in the brainstem/cerebellum as early as 9 weeks of age. In quantitative assessments, phosphorylated α-synuclein gradually and successively accumulated at 12, 24, and 30 weeks in bi-transgenic mice. By contrast, no phosphorylated α-synuclein was detected in wild-type, tetO-SNCA*A53T, or Plp1-tTA mice at any age examined. Pronounced demyelination and tubulin polymerisation, promoting protein-positive oligodendrocytic loss, was closely associated with phosphorylated α-synuclein aggregates at 24 and 30 weeks of age. Early inhibition of mutant α-synuclein expression by doxycycline diet at 23 weeks led to fully recovered demyelination; inhibition at 27 weeks led to persistent demyelination with glial reactions, despite resolving phosphorylated α-synuclein aggregates. In conclusion, our bi-transgenic mice exhibited progressively increasing demyelination and neuroaxonal loss in the brainstem/cerebellum, with rapidly progressive motor deterioration in adulthood. These mice showed marked microglial and astrocytic reactions with inflammation that was closely associated with phosphorylated α-synuclein aggregates. These features closely mimic human MSA-C pathology. Notably, our model is the first to suggest that α-synuclein oligomers may spread from oligodendrocytes to neurons in transgenic mice with human α-synuclein expression in oligodendrocytes. This model of MSA is therefore particularly useful for elucidating the in vivo mechanisms of α-synuclein spreading from glia to neurons, and for developing therapies that target glial reactions and/or α-synuclein oligomer spreading and aggregate formation in MSA.

2.
Nat Commun ; 15(1): 5551, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956067

RESUMO

Genetically-encoded dopamine (DA) sensors enable high-resolution imaging of DA release, but their ability to detect a wide range of extracellular DA levels, especially tonic versus phasic DA release, is limited by their intrinsic affinity. Here we show that a human-selective dopamine receptor positive allosteric modulator (PAM) can be used to boost sensor affinity on-demand. The PAM enhances DA detection sensitivity across experimental preparations (in vitro, ex vivo and in vivo) via one-photon or two-photon imaging. In vivo photometry-based detection of optogenetically-evoked DA release revealed that DETQ administration produces a stable 31 minutes window of potentiation without effects on animal behavior. The use of the PAM revealed region-specific and metabolic state-dependent differences in tonic DA levels and enhanced single-trial detection of behavior-evoked phasic DA release in cortex and striatum. Our chemogenetic strategy can potently and flexibly tune DA imaging sensitivity and reveal multi-modal (tonic/phasic) DA signaling across preparations and imaging approaches.


Assuntos
Dopamina , Optogenética , Dopamina/metabolismo , Animais , Humanos , Optogenética/métodos , Camundongos , Masculino , Corpo Estriado/metabolismo , Corpo Estriado/diagnóstico por imagem , Receptores Dopaminérgicos/metabolismo , Receptores Dopaminérgicos/genética , Camundongos Endogâmicos C57BL , Regulação Alostérica , Fotometria/métodos , Células HEK293
3.
Elife ; 122024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38567902

RESUMO

Dopamine and orexins (hypocretins) play important roles in regulating reward-seeking behaviors. It is known that hypothalamic orexinergic neurons project to dopamine neurons in the ventral tegmental area (VTA), where they can stimulate dopaminergic neuronal activity. Although there are reciprocal connections between dopaminergic and orexinergic systems, whether and how dopamine regulates the activity of orexin neurons is currently not known. Here we implemented an opto-Pavlovian task in which mice learn to associate a sensory cue with optogenetic dopamine neuron stimulation to investigate the relationship between dopamine release and orexin neuron activity in the lateral hypothalamus (LH). We found that dopamine release can be evoked in LH upon optogenetic stimulation of VTA dopamine neurons and is also naturally evoked by cue presentation after opto-Pavlovian learning. Furthermore, orexin neuron activity could also be upregulated by local stimulation of dopaminergic terminals in the LH in a way that is partially dependent on dopamine D2 receptors (DRD2). Our results reveal previously unknown orexinergic coding of reward expectation and unveil an orexin-regulatory axis mediated by local dopamine inputs in the LH.


Assuntos
Região Hipotalâmica Lateral , Área Tegmentar Ventral , Camundongos , Animais , Orexinas , Área Tegmentar Ventral/fisiologia , Dopamina , Receptores de Dopamina D2 , Neurônios Dopaminérgicos , Recompensa
4.
Nat Methods ; 20(9): 1426-1436, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37474807

RESUMO

Genetically encoded indicators engineered from G-protein-coupled receptors are important tools that enable high-resolution in vivo neuromodulator imaging. Here, we introduce a family of sensitive multicolor norepinephrine (NE) indicators, which includes nLightG (green) and nLightR (red). These tools report endogenous NE release in vitro, ex vivo and in vivo with improved sensitivity, ligand selectivity and kinetics, as well as a distinct pharmacological profile compared with previous state-of-the-art GRABNE indicators. Using in vivo multisite fiber photometry recordings of nLightG, we could simultaneously monitor optogenetically evoked NE release in the mouse locus coeruleus and hippocampus. Two-photon imaging of nLightG revealed locomotion and reward-related NE transients in the dorsal CA1 area of the hippocampus. Thus, the sensitive NE indicators introduced here represent an important addition to the current repertoire of indicators and provide the means for a thorough investigation of the NE system.


Assuntos
Locus Cerúleo , Norepinefrina , Animais , Camundongos , Locus Cerúleo/fisiologia , Hipocampo/fisiologia , Receptores Acoplados a Proteínas G
5.
Neuropsychopharmacology ; 48(3): 448-458, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36071131

RESUMO

Addiction-related compulsion-like behavior can be modeled in rodents with drug self-administration (SA) despite harmful consequences. Recent studies suggest that the potentiation of glutamatergic transmission at the orbitofrontal cortex (OFC) to dorsal striatum (DS) synapses drives the transition from controlled to compulsion-like SA. However, the timing of the induction of this synaptic plasticity remains elusive. Here, mice were first allowed to intravenously self-administer cocaine. When mice had to endure a risk of electrical foot shock, only a fraction persevered in cocaine SA. In these persevering mice, we recorded high A/N ratios (AMPA-R/NMDA-R: α-amino-3hydroxy-5-methyl-4-isoxazolepropionic acid receptor/N-methyl-D-aspartate receptor) in both types of spiny projection neurons (i.e., D1 and D2 dopamine receptor-expressing SPNs). By contrast, when we prepared slices at the end of the acquisition period, in all mice, the A/N was high in D1R- but not D2R-SPNs. These results indicate that the transition to compulsion-like cocaine SA emerges during the punishment sessions, where synapses onto D2R-SPNs are strengthened. In renouncing individuals, the cocaine-evoked strengthening in D1R-SPNs is lost. Our study thus reveals the cell-type specific sequence of the induction of plasticity that eventually may cause compulsion-like SA.


Assuntos
Comportamento Aditivo , Cocaína , Camundongos , Animais , Punição , Núcleo Accumbens/metabolismo , Plasticidade Neuronal/fisiologia , Receptores de Dopamina D1/metabolismo
6.
Cell Chem Biol ; 29(12): 1729-1738.e8, 2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36481097

RESUMO

Orexin neuropeptides carry out important neuromodulatory functions in the brain, yet tools to precisely control the activation of endogenous orexin signaling are lacking. Here, we developed a photocaged orexin-B (photo-OXB) through a C-terminal photocaging strategy. We show that photo-OXB is unable to activate its cognate receptors in the dark but releases functionally active native orexin-B upon uncaging by illumination with UV-visible (UV-vis) light (370-405 nm). We established an all-optical assay combining photo-OXB with a genetically encoded orexin biosensor and used it to characterize the efficiency and spatial profile of photo-OXB uncaging. Finally, we demonstrated that photo-OXB enables optical control over orexin signaling with fine temporal precision both in vitro and ex vivo. Thus, our photocaging strategy and photo-OXB advance the chemical biological toolkit by introducing a method for the optical control of peptide signaling and physiological function.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular , Neuropeptídeos , Orexinas , Receptores de Orexina , Transdução de Sinais , Receptores Acoplados a Proteínas G
7.
J Exp Med ; 219(6)2022 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-35579694

RESUMO

Neural circuits between lesions are one mechanism through which local inflammation spreads to remote positions. Here, we show the inflammatory signal on one side of the joint is spread to the other side via sensory neuron-interneuron crosstalk, with ATP at the core. Surgical ablation or pharmacological inhibition of this neural pathway prevented inflammation development on the other side. Mechanistic analysis showed that ATP serves as both a neurotransmitter and an inflammation enhancer, thus acting as an intermediary between the local inflammation and neural pathway that induces inflammation on the other side. These results suggest blockade of this neural pathway, which is named the remote inflammation gateway reflex, may have therapeutic value for inflammatory diseases, particularly those, such as rheumatoid arthritis, in which inflammation spreads to remote positions.


Assuntos
Interneurônios , Células Receptoras Sensoriais , Trifosfato de Adenosina , Humanos , Inflamação , Reflexo/fisiologia
8.
Biol Psychiatry ; 90(12): 808-818, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34688471

RESUMO

BACKGROUND: Activation of the mesolimbic dopamine system is positively reinforcing. After repeated activation, some individuals develop compulsive reward-seeking behavior, which is a core symptom of addiction. However, the underlying neural mechanism remains elusive. METHODS: We trained mice in a seek-take chain, rewarded by optogenetic dopamine neuron self-stimulation. After compulsivity was evaluated, AMPA/NMDA ratio was measured at three distinct corticostriatal pathways confirmed by retrograde labeling and anterograde synaptic connectivity. Fiber photometry method and chemogenetics were used to parse the contribution of orbitofrontal cortex afferents onto the dorsal striatum (DS) during the behavioral task. We established a causal link between DS activity and compulsivity using optogenetic inhibition. RESULTS: Mice that persevered when seeking was punished exhibited an increased AMPA/NMDA ratio selectively at orbitofrontal cortex to DS synapses. In addition, an activity peak of spiny projection neurons in the DS at the moment of signaled reward availability was detected. Chemogenetic inhibition of orbitofrontal cortex neurons curbed the activity peak and reduced punished reward seeking, as did optogenetic hyperpolarization of spiny projection neurons time-locked to the cue predicting reward availability. CONCLUSIONS: Our results suggest that compulsive individuals display stronger neuronal activity in the DS during the cue predicting reward availability even when at the risk of punishment, nurturing further compulsive reward seeking.


Assuntos
Punição , Recompensa , Animais , Comportamento Compulsivo , Neurônios Dopaminérgicos , Camundongos , Córtex Pré-Frontal
9.
Phys Chem Chem Phys ; 22(35): 19502-19511, 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32832961

RESUMO

Changing the electronic structure of materials by pressure and the accompanying changes in optical properties have attracted scientific interest. We have reported that the energy position of the conduction band (CB) bottom and the crystal field splitting of the Ce3+:5d excited level in Y3Al5-xGaxO12:Ce3+ are changed by applying pressure, which results in the red shifting of the Ce3+:5d → 4f luminescence and the increase of the quenching temperature. We also reported dramatic improvement of the persistent luminescence performance by either Cr3+ or Yb3+ codoping into the Y3Al5-xGaxO12:Ce3+ phosphors. The different trap depths formed by Cr3+ and Yb3+ affect the initial persistent luminescence intensity and the persistent luminescence duration. In this study, the effect of pressure on the persistent luminescence performance was investigated. For the Y3AlGa4O12:Ce3+-Yb3+ phosphor, the slope of persistent luminescence decay curve becomes more gentle with increasing pressure, while for the Y3AlGa4O12:Ce3+-Cr3+ phosphor the slope becomes steeper. These results indicate that the trap depth of Yb3+ becomes deeper and that of Cr3+ becomes shallower with increasing pressure. Based on the pressure-dependence of the luminescence quenching and the trap depth change estimated from the decay slopes, the relative electronic energies of the CB bottom and the Yb2+ (4f14) or Cr2+ (3d4) levels are discussed. The CB bottom energy is increased relative to the ground 1S0 state of Yb2+ with increasing pressure, which results in deepening of the electron trap depth of the Yb2+ state. The opposite tendency of the Cr3+ codoped sample was described by a decreasing tendency of the energy gap between the CB bottom and the Cr2+:eg level, the relative energy level of which is increased by the increase of the crystal field with increasing pressure in the garnet host material, where the electron-trapping Cr2+ ions take the high spin state (t32ge1g) rather than the low-spin state (t42g).

10.
Front Neurol ; 10: 600, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31231307

RESUMO

We describe a 60-year-old woman with combined central and peripheral demyelination who presented with obstinate constipation, weakness in the lower limbs, and a bilateral sensory disturbance below her chest followed by girdle sensation in the right region of the abdomen, which was responsive to steroid therapy and plasmapheresis. Serum anti-lactosylceramide antibody was positive without anti-neurofascin 155 antibody or anti-galactocerebroside antibody positivity. Two months later, the patient had a first relapse that was responsive to steroid treatment. A nerve conduction study confirmed reversible conduction failure (RCF) in both episodes. Our case is unique in that she had an RCF episode as well as some similarities to encephalomyeloradiculoneuropathy.

11.
Mult Scler Relat Disord ; 29: 108-110, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30708307

RESUMO

There are no specific radiologic features in MOG-Ab (autoantibodies directed against myelin oligodendrocyte glycoprotein)-associated diseases. We present two MOG-Ab-positive patients with symmetrical lesions in the bilateral cingulate cortex of the frontal and parietal lobes. Those lesions showed hyperperfusion in acute phase and hypoperfusion in chronic phase on brain SPECT. In both patients, steroid therapy was effective in acute phase and for prevention of recurrence. High signal in the bilateral cingulate cortex on MR T2-weighted and FLAIR images might to be one of the unique findings considered MOG-Ab associated diseases.


Assuntos
Autoanticorpos/imunologia , Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/patologia , Giro do Cíngulo/patologia , Glicoproteína Mielina-Oligodendrócito/imunologia , Esteroides/farmacologia , Doença Aguda , Adulto , Doença Crônica , Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/diagnóstico por imagem , Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/tratamento farmacológico , Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/imunologia , Feminino , Giro do Cíngulo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Prevenção Secundária , Tomografia Computadorizada de Emissão de Fóton Único
12.
Eur J Med Genet ; 62(12): 103594, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30503856

RESUMO

Distal hereditary motor neuropathies (dHMNs) comprise a group of clinically and genetically heterogeneous inherited lower motor neuron syndromes mainly characterized by a distal-predominant pattern of progressive muscle atrophy, weakness and hyporeflexia, without sensory dysfunction. Although at least 21 causative genes for dHMN have been reported, mutational scanning of these genes often fails to identify the causative variants in dHMN cohorts, suggesting that additional causative genes remain to be identified. We studied a four-generation pedigree of a Japanese family with autosomal dominant dHMN to provide insight into the pathogenetic basis of the disease. Neurological examinations were performed on all six family members enrolled in this study. Whole-exome sequencing (WES) was used to identify the causative gene for dHMN. The clinical features of the patients included muscle weakness with distal extensor dominancy in the lower extremities, accompanied by facial and neck flexor muscle impairment, no sensory involvement, and areflexia. Nerve conduction studies demonstrated axonal changes mainly in the peroneal nerve. WES combined with rigorous filtering revealed three missense variants (NM_001083964: c.851G > A [p.Arg284His] in TDRKH, NM_002858: c.1654G > T [p.Gly552Cys] in ABCD3, NM_001005164: c.898A > T [p.Ile300Phe], in OR52E2). The variant in TDRKH is located in a conserved region of the tudor domain which is also present in the survival of motor neuron (SMN) protein, encoded by the SMN1 gene. Therefore, we concluded the variant in TDRKH is likely to be responsible for dHMN in our pedigree.


Assuntos
Transtornos Heredodegenerativos do Sistema Nervoso/genética , Doença dos Neurônios Motores/genética , Proteínas de Ligação a RNA/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Genes Dominantes , Transtornos Heredodegenerativos do Sistema Nervoso/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Doença dos Neurônios Motores/patologia , Músculo Esquelético/fisiopatologia , Mutação de Sentido Incorreto , Linhagem , Nervo Fibular/fisiopatologia , Reflexo
13.
Nature ; 564(7736): 366-371, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30568192

RESUMO

Activation of the mesolimbic dopamine system reinforces goal-directed behaviours. With repetitive stimulation-for example, by chronic drug abuse-the reinforcement may become compulsive and intake continues even in the face of major negative consequences. Here we gave mice the opportunity to optogenetically self-stimulate dopaminergic neurons and observed that only a fraction of mice persevered if they had to endure an electric shock. Compulsive lever pressing was associated with an activity peak in the projection terminals from the orbitofrontal cortex (OFC) to the dorsal striatum. Although brief inhibition of OFC neurons temporarily relieved compulsive reinforcement, we found that transmission from the OFC to the striatum was permanently potentiated in persevering mice. To establish causality, we potentiated these synapses in vivo in mice that stopped optogenetic self-stimulation of dopamine neurons because of punishment; this led to compulsive lever pressing, whereas depotentiation in persevering mice had the converse effect. In summary, synaptic potentiation of transmission from the OFC to the dorsal striatum drives compulsive reinforcement, a defining symptom of addiction.


Assuntos
Comportamento Aditivo/fisiopatologia , Comportamento Compulsivo/fisiopatologia , Modelos Neurológicos , Plasticidade Neuronal , Animais , Comportamento Aditivo/patologia , Comportamento Aditivo/psicologia , Comportamento Compulsivo/patologia , Comportamento Compulsivo/psicologia , Neurônios Dopaminérgicos/fisiologia , Estimulação Elétrica , Feminino , Masculino , Camundongos , Neostriado/citologia , Neostriado/fisiologia , Inibição Neural , Vias Neurais , Optogenética , Córtex Pré-Frontal/citologia , Córtex Pré-Frontal/fisiologia , Punição , Reforço Psicológico , Processos Estocásticos , Sinapses/metabolismo , Transmissão Sináptica
14.
Cell Rep ; 17(9): 2405-2417, 2016 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-27880913

RESUMO

Here, we show neuronal inactivation-induced presynaptic remodeling and involvement of the mammalian homolog of Diaphanous (mDia) and Rho-associated coiled-coil-containing kinase (ROCK), Rho-regulated modulators of actin and myosin, in this process. We find that social isolation induces inactivation of nucleus accumbens (NAc) neurons associated with elevated anxiety-like behavior, and that mDia in NAc neurons is essential in this process. Upon inactivation of cultured neurons, mDia induces circumferential actin filaments around the edge of the synaptic cleft, which contract the presynaptic terminals in a ROCK-dependent manner. Social isolation induces similar mDia-dependent presynaptic contraction at GABAergic synapses from NAc neurons in the ventral tegmental area (VTA) associated with reduced synaptic efficacy. Optogenetic stimulation of NAc neurons rescues the anxiety phenotype, and injection of a specific ROCK inhibitor, Y-27632, into the VTA reverses both presynaptic contraction and the behavioral phenotype. mDia-ROCK signaling thus mediates actin-dependent presynaptic remodeling in inactivated NAc neurons, which underlies synaptic plasticity in emotional behavioral responses.


Assuntos
Actinas/metabolismo , Ansiedade/metabolismo , Proteínas de Transporte/metabolismo , Terminações Pré-Sinápticas/metabolismo , Quinases Associadas a rho/metabolismo , Citoesqueleto de Actina/metabolismo , Envelhecimento , Amidas/farmacologia , Animais , Comportamento Animal , Encéfalo/metabolismo , Células Cultivadas , Forminas , Neurônios GABAérgicos/metabolismo , Camundongos Endogâmicos C57BL , Núcleo Accumbens/metabolismo , Optogenética , Fenótipo , Terminações Pré-Sinápticas/efeitos dos fármacos , Piridinas/farmacologia , Isolamento Social , Área Tegmentar Ventral/metabolismo
15.
Neuron ; 88(3): 553-64, 2015 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-26593092

RESUMO

Feeding satisfies metabolic need but is also controlled by external stimuli, like palatability or predator threat. Nucleus accumbens shell (NAcSh) projections to the lateral hypothalamus (LH) are implicated in mediating such feeding control, but the neurons involved and their mechanism of action remain elusive. We show that dopamine D1R-expressing NAcSh neurons (D1R-MSNs) provide the dominant source of accumbal inhibition to LH and provide rapid control over feeding via LH GABA neurons. In freely feeding mice, D1R-MSN activity reduced during consumption, while their optogenetic inhibition prolonged feeding, even in the face of distracting stimuli. Conversely, activation of D1R-MSN terminals in LH was sufficient to abruptly stop ongoing consumption, even during hunger. Direct inhibition of LH GABA neurons, which received input from D1R-MSNs, fully recapitulated these findings. Together, our study resolves a feeding circuit that overrides immediate metabolic need to allow rapid consumption control in response to changing external stimuli. VIDEO ABSTRACT.


Assuntos
Comportamento Alimentar/fisiologia , Região Hipotalâmica Lateral/fisiologia , Neurônios/fisiologia , Núcleo Accumbens/fisiologia , Receptores de Dopamina D1/fisiologia , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Vias Neurais/fisiologia , Técnicas de Cultura de Órgãos
16.
Sci Rep ; 5: 14230, 2015 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-26382974

RESUMO

While aging is unavoidable, the aging mechanism is still unclear because of its complexity. Smoking causes premature death and is considered as an environmental aging accelerator. In the present study, we focused on the influence of smoking to the serum concentration of anti-aging protein α-klotho (αKl) and the ß-klotho-associated protein fibroblast growth factor (FGF)-21 in men. Subjects consisted of apparently healthy men over 40 years of age who underwent health examination. Physical and biochemical parameters, including the levels of several cytokines and growth factors, were obtained from the subjects. Among middle-aged men (46.1 ± 5.1 years), serum levels of FGF-21, soluble αKl (sαKl), and inflammation-related cytokine interleukin (IL)-6 were significantly higher in smokers than in never-smokers. Serum levels of FGF-21 increased and correlated with alanine transaminase, γ guanosine-5'-triphosphate, and total cholesterol only in smokers, suggesting FGF-21 as a metabolic disorder-related factor in smokers. In aged men (60.3 ± 1.7 years), although the serum levels of sαKl in never-smokers were low, smokers showed highly increased serum levels of sαKl. Serum levels of sαKl was correlated with IL-6 in middle-aged never-smokers, suggesting sαKl regulates IL-6. However, this correlation was disrupted in smokers and aged men.


Assuntos
Glucuronidase/sangue , Hábitos , Vigilância em Saúde Pública , Fumar/efeitos adversos , Adulto , Envelhecimento/sangue , Biomarcadores , Estudos Transversais , Citocinas/sangue , Meio Ambiente , Fatores de Crescimento de Fibroblastos/sangue , Humanos , Inflamação/metabolismo , Proteínas Klotho , Masculino , Pessoa de Meia-Idade , Estresse Fisiológico , Regulação para Cima
17.
Elife ; 42015 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-26193120

RESUMO

Although pain is a common symptom of various diseases and disorders, its contribution to disease pathogenesis is not well understood. Here we show using murine experimental autoimmune encephalomyelitis (EAE), a model for multiple sclerosis (MS), that pain induces EAE relapse. Mechanistic analysis showed that pain induction activates a sensory-sympathetic signal followed by a chemokine-mediated accumulation of MHC class II+CD11b+ cells that showed antigen-presentation activity at specific ventral vessels in the fifth lumbar cord of EAE-recovered mice. Following this accumulation, various immune cells including pathogenic CD4+ T cells recruited in the spinal cord in a manner dependent on a local chemokine inducer in endothelial cells, resulting in EAE relapse. Our results demonstrate that a pain-mediated neural signal can be transformed into an inflammation reaction at specific vessels to induce disease relapse, thus making this signal a potential therapeutic target.


Assuntos
Encefalomielite Autoimune Experimental/patologia , Esclerose Múltipla/patologia , Dor , Animais , Células Apresentadoras de Antígenos/imunologia , Linfócitos T CD4-Positivos/imunologia , Quimiocinas/metabolismo , Modelos Animais de Doenças , Camundongos , Recidiva , Medula Espinal/patologia
18.
Nat Commun ; 6: 7474, 2015 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-26081938

RESUMO

KDEL receptors are responsible for retrotransporting endoplasmic reticulum (ER) chaperones from the Golgi complex to the ER. Here we describe a role for KDEL receptor 1 (KDELR1) that involves the regulation of integrated stress responses (ISR) in T cells. Designing and using an N-ethyl-N-nitrosourea (ENU)-mutant mouse line, T-Red (naïve T-cell reduced), we show that a point mutation in KDELR1 is responsible for the reduction in the number of naïve T cells in this model owing to an increase in ISR. Mechanistic analysis shows that KDELR1 directly regulates protein phosphatase 1 (PP1), a key phosphatase for ISR in naïve T cells. T-Red KDELR1 does not associate with PP1, resulting in reduced phosphatase activity against eIF2α and subsequent expression of stress responsive genes including the proapoptotic factor Bim. These results demonstrate that KDELR1 regulates naïve T-cell homeostasis by controlling ISR.


Assuntos
Proteína Fosfatase 1/metabolismo , Receptores de Peptídeos/metabolismo , Linfócitos T/fisiologia , Sequência de Aminoácidos , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Proteína 11 Semelhante a Bcl-2 , Fator de Iniciação 2 em Eucariotos/metabolismo , Feminino , Homeostase , Memória Imunológica , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Knockout , Dados de Sequência Molecular , Fenótipo , Mutação Puntual , Proteínas Proto-Oncogênicas/metabolismo , Receptores de Peptídeos/genética , Estresse Fisiológico
19.
J Immunol ; 194(3): 1039-46, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25556244

RESUMO

In this study, we investigated the relationship between several growth factors and inflammation development. Serum concentrations of epiregulin, amphiregulin, betacellulin, TGF-α, fibroblast growth factor 2, placental growth factor (PLGF), and tenascin C were increased in rheumatoid arthritis patients. Furthermore, local blockades of these growth factors suppressed the development of cytokine-induced arthritis in mice by inhibiting chemokine and IL-6 expressions. We found that epiregulin expression was early and followed by the induction of other growth factors at different sites of the joints. The same growth factors then regulated the expression of epiregulin at later time points of the arthritis. These growth factors were increased in patients suffering from multiple sclerosis (MS) and also played a role in the development of an MS model, experimental autoimmune encephalomyelitis. The results suggest that the temporal expression of growth factors is involved in the inflammation development seen in several diseases, including rheumatoid arthritis and MS. Therefore, various growth factor pathways might be good therapeutic targets for various inflammatory diseases.


Assuntos
Epirregulina/metabolismo , Regulação da Expressão Gênica , Inflamação/genética , Inflamação/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Animais , Artrite Reumatoide/genética , Artrite Reumatoide/imunologia , Artrite Reumatoide/metabolismo , Citocinas/sangue , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/metabolismo , Humanos , Inflamação/imunologia , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Camundongos , Esclerose Múltipla/genética , Esclerose Múltipla/imunologia , Esclerose Múltipla/metabolismo , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais
20.
Cancer Res ; 74(1): 8-14, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24362915

RESUMO

Tumor-associated inflammation can induce various molecules expressed from the tumors themselves or surrounding cells to create a microenvironment that potentially promotes cancer development. Inflammation, particularly chronic inflammation, is often linked to cancer development, even though its evolutionary role should impair nonself objects including tumors. The inflammation amplifier, a hyperinducer of chemokines in nonimmune cells, is the principal machinery for inflammation and is activated by the simultaneous stimulation of NF-κB and STAT3. We have redefined inflammation as local activation of the inflammation amplifier, which causes an accumulation of various immune cells followed by dysregulation of local homeostasis. Genes related to the inflammation amplifier have been genetically associated with various human inflammatory diseases. Here, we describe how cancer-associated genes, including interleukin (IL)-6, Ptgs2, ErbB1, Gas1, Serpine1, cMyc, and Vegf-α, are strongly enriched in genes related to the amplifier. The inflammation amplifier is activated by the stimulation of cytokines, such as TNF-α, IL-17, and IL-6, resulting in the subsequent expression of various target genes for chemokines and tumor-related genes like BCL2L11, CPNE7, FAS, HIF1-α, IL-1RAP, and SOD2. Thus, we conclude that inflammation does indeed associate with the development of cancer. The identified genes associated with the inflammation amplifier may thus make potential therapeutic targets of cancers.


Assuntos
Inflamação/metabolismo , Inflamação/patologia , Neoplasias/metabolismo , Neoplasias/patologia , Animais , Humanos , Transdução de Sinais , Microambiente Tumoral
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