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1.
Nat Commun ; 11(1): 5113, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-33037215

RESUMO

Striatal activity is dynamically modulated by acetylcholine and dopamine, both of which are essential for basal ganglia function. Synchronized pauses in the activity of striatal cholinergic interneurons (ChINs) are correlated with elevated activity of midbrain dopaminergic neurons, whereas synchronous firing of ChINs induces local release of dopamine. The mechanisms underlying ChIN synchronization and its interplay with dopamine release are not fully understood. Here we show that polysynaptic inhibition between ChINs is a robust network motif and instrumental in shaping the network activity of ChINs. Action potentials in ChINs evoke large inhibitory responses in multiple neighboring ChINs, strong enough to suppress their tonic activity. Using a combination of optogenetics and chemogenetics we show the involvement of striatal tyrosine hydroxylase-expressing interneurons in mediating this inhibition. Inhibition between ChINs is attenuated by dopaminergic midbrain afferents acting presynaptically on D2 receptors. Our results present a novel form of interaction between striatal dopamine and acetylcholine dynamics.


Assuntos
Neurônios Colinérgicos/metabolismo , Corpo Estriado/citologia , Interneurônios/metabolismo , Inibição Neural/fisiologia , Transmissão Sináptica/fisiologia , Acetilcolina/fisiologia , Animais , Condicionamento Clássico , Corpo Estriado/fisiologia , Dopamina , Feminino , Masculino , Mesencéfalo/citologia , Mesencéfalo/fisiologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Técnicas de Patch-Clamp , Receptores de Dopamina D2/metabolismo , Recompensa
2.
PLoS One ; 15(9): e0238637, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32903270

RESUMO

Neonicotinoids, a class of insecticides structurally similar to nicotine that target biting and sucking insects, are the most widely used insecticides today, in part due to their supposed low toxicity in other organisms. However, a growing body of research has found that even low doses of neonicotinoids can induce unexpected negative effects on the physiology and survival of a wide range of non-target organisms. Importantly, no work has been done on the commercial formulations of pesticides that include imidacloprid as the active ingredient, but that also contain many other components. The present study examines the sublethal effects of "Tree and Shrub"™ ("T+S"), a commercial insecticide containing the neonicotinoid imidacloprid as its active ingredient, on Caenorhabditis elegans. We discovered that "T+S" significantly stunted the overall growth in wildtype nematodes, an effect that was exacerbated by concurrent exposure to heat stress. "T+S" also negatively impacted fecundity as measured by increased germline apoptosis, a decrease in egg-laying, and fewer viable offspring. Lastly, exposure to "T+S" resulted in degenerative changes in nicotinic cholinergic neurons in wildtype nematodes. As a whole, these findings demonstrate widespread toxic effects of neonicotinoids to critical functions in nematodes.


Assuntos
Caenorhabditis elegans/crescimento & desenvolvimento , Caenorhabditis elegans/fisiologia , Inseticidas/toxicidade , Locomoção/efeitos dos fármacos , Neonicotinoides/toxicidade , Animais , Apoptose/efeitos dos fármacos , Caenorhabditis elegans/efeitos dos fármacos , Neurônios Colinérgicos/efeitos dos fármacos , Neurônios Colinérgicos/metabolismo , Aberrações Cromossômicas , Fertilidade/efeitos dos fármacos , Células Germinativas/citologia , Células Germinativas/efeitos dos fármacos , Resposta ao Choque Térmico , Degeneração Neural/patologia , Oviposição/efeitos dos fármacos , Reprodução/efeitos dos fármacos
3.
Life Sci ; 260: 118388, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32890602

RESUMO

Damage to the cholinergic system in central nervous system injuries such as traumatic brain injury (TBI) and neurodegenerative diseases leads to impaired learning and cognition. Neural stem cells (NSCs) have self-renewal capacity and multi-directional differentiation potential and considered the best source of cells for cell replacement therapy. However, how to promote the differentiation of NSCs into neurons is a major challenge in current research. Lhx8 has a specific effect on the development of the cholinergic nervous system, but its exact function is unclear. In this study, we found that Lhx8 could regulate the expression of Growth arrest-specific (GAS)5 which has been implicated in cancer but was less studied in the nervous system. Additionally, results from PCR, fluorescence in situ hybridization, and immunocytochemical analyses showed that GAS5 is mainly expressed in the cytoplasm of hippocampal neural stems cells and promotes their differentiation into neurons; the Morris water maze test demonstrated that GAS5 overexpression restored learning and memory in rats with cholinergic injury. These findings indicate that GAS5, which is regulated by Lhx8, improve brain function following cholinergic nerve injury.


Assuntos
Lesões Encefálicas/fisiopatologia , Neurônios Colinérgicos/patologia , Proteínas com Homeodomínio LIM/metabolismo , Aprendizagem/fisiologia , Memória/fisiologia , Células-Tronco Neurais/patologia , RNA Longo não Codificante/genética , Fatores de Transcrição/metabolismo , Acetilcolina/metabolismo , Animais , Colina O-Acetiltransferase/metabolismo , Neurônios Colinérgicos/metabolismo , Regulação da Expressão Gênica , Proteínas com Homeodomínio LIM/genética , Células-Tronco Neurais/metabolismo , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Fatores de Transcrição/genética
4.
Life Sci ; 259: 118229, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32781065

RESUMO

AIMS: Cholinergic neurons are distributed in brain areas containing growth hormone (GH)-responsive cells. We determined if cholinergic neurons are directly responsive to GH and the metabolic consequences of deleting the GH receptor (GHR) specifically in choline acetyltransferase (ChAT)-expressing cells. MAIN METHODS: Mice received an acute injection of GH to detect neurons co-expressing ChAT and phosphorylated STAT5 (pSTAT5), a well-established marker of GH-responsive cells. For the physiological studies, mice carrying ablation of GHR exclusively in ChAT-expressing cells were produced and possible changes in energy and glucose homeostasis were determined when consuming regular chow or high-fat diet (HFD). KEY FINDINGS: The majority of cholinergic neurons in the arcuate nucleus (60%) and dorsomedial nucleus (84%) of the hypothalamus are directly responsive to GH. Approximately 34% of pre-ganglionic parasympathetic neurons in the dorsal motor nucleus of the vagus also exhibited GH-induced pSTAT5. GH-induced pSTAT5 in these ChAT neurons was absent in GHR ChAT knockout mice. Mice carrying ChAT-specific GHR deletion, either in chow or HFD, did not exhibit significant changes in body weight, body adiposity, lean body mass, food intake, energy expenditure, respiratory quotient, ambulatory activity, serum leptin levels, glucose tolerance, insulin sensitivity and metabolic responses to 2-deoxy-d-glucose. However, GHR deletion in ChAT neurons caused decreased hypothalamic Pomc mRNA levels in HFD mice. SIGNIFICANCE: Cholinergic neurons that regulate the metabolism are directly responsive to GH, although GHR signaling in these cells is not required for energy and glucose homeostasis. Thus, the physiological importance of GH action on cholinergic neurons still needs to be identified.


Assuntos
Neurônios Colinérgicos/metabolismo , Hormônio do Crescimento/metabolismo , Receptores da Somatotropina/metabolismo , Acetilcolina/metabolismo , Animais , Núcleo Arqueado do Hipotálamo/metabolismo , Peso Corporal , Colina O-Acetiltransferase/genética , Colina O-Acetiltransferase/metabolismo , Neurônios Colinérgicos/efeitos dos fármacos , Dieta Hiperlipídica , Metabolismo Energético , Glucose/metabolismo , Hormônio do Crescimento/fisiologia , Hipotálamo/metabolismo , Resistência à Insulina/genética , Leptina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores da Somatotropina/genética , Fator de Transcrição STAT5/metabolismo , Nervo Vago/metabolismo
5.
Ecotoxicol Environ Saf ; 203: 110975, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32678756

RESUMO

Manganese (Mn) produces cholinergic neuronal loss in basal forebrain (BF) region that was related to cognitive dysfunction induced after single and repeated Mn treatment. All processes that generate cholinergic neuronal loss in BF remain to be understood. Mn exposure may produce the reduction of BF cholinergic neurons by increasing amyloid beta (Aß) and phosphorylated Tau (pTau) protein levels, altering heat shock proteins' (HSPs) expression, disrupting proteasome P20S activity and generating oxidative stress. These mechanisms, described to be altered by Mn in regions different than BF, could lead to the memory and learning process alteration produced after Mn exposure. The research performed shows that single and repeated Mn treatment of SN56 cholinergic neurons from BF induces P20S inhibition, increases Aß and pTau protein levels, produces HSP90 and HSP70 proteins expression alteration, and oxidative stress generation, being the last two effects mediated by NRF2 pathway alteration. The increment of Aß and pTau protein levels was mediated by HSPs and proteasome dysfunction. All these mechanisms mediated the cell decline observed after Mn treatment. Our results are relevant because they may assist to reveal the processes leading to the neurotoxicity and cognitive alterations observed after Mn exposure.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Prosencéfalo Basal/efeitos dos fármacos , Neurônios Colinérgicos/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Manganês/toxicidade , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas tau/metabolismo , Animais , Prosencéfalo Basal/metabolismo , Prosencéfalo Basal/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Neurônios Colinérgicos/metabolismo , Neurônios Colinérgicos/patologia , Relação Dose-Resposta a Droga , Poluentes Ambientais/metabolismo , Manganês/metabolismo , Camundongos , Estresse Oxidativo/efeitos dos fármacos
6.
PLoS One ; 15(5): e0221669, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32437347

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive memory loss and cognitive disturbance as a consequence of the loss of cholinergic neurons in the brain, neuritic plaques and hyperphosphorylation of TAU protein. Although the underlying mechanisms leading to these events are unclear, mutations in presenilin 1 (PSEN1), e.g., E280A (PSEN1 E280A), are causative factors for autosomal dominant early-onset familial AD (FAD). Despite advances in the understanding of the physiopathology of AD, there are no efficient therapies to date. Limitations in culturing brain-derived live neurons might explain the limited effectiveness of AD research. Here, we show that mesenchymal stromal (stem) cells (MSCs) can be used to model FAD, providing novel opportunities to study cellular mechanisms and to establish therapeutic strategies. Indeed, we cultured MSCs with the FAD mutation PSEN1 E280A and wild-type (WT) PSEN1 from umbilical cords and characterized the transdifferentiation of these cells into cholinergic-like neurons (ChLNs). PSEN1 E280A ChLNs but not WT PSEN1 ChLNs exhibited increased intracellular soluble amyloid precursor protein (sAPPf) fragments and extracellular Aß42 peptide and TAU phosphorylation (at residues Ser202/Thr205), recapitulating the molecular pathogenesis of FAD caused by mutant PSEN1. Furthermore, PSEN1 E280A ChLNs presented oxidative stress (OS) as evidenced by the oxidation of DJ-1Cys106-SH into DJ-1Cys106-SO3 and the detection of DCF-positive cells and apoptosis markers such as activated pro-apoptosis proteins p53, c-JUN, PUMA and CASPASE-3 and the concomitant loss of the mitochondrial membrane potential and DNA fragmentation. Additionally, mutant ChLNs displayed Ca2+ flux dysregulation and deficient acetylcholinesterase (AChE) activity compared to control ChLNs. Interestingly, the inhibitor JNK SP600125 almost completely blocked TAU phosphorylation. Our findings demonstrate that FAD MSC-derived cholinergic neurons with the PSEN1 E280A mutation provide important clues for the identification of targetable pathological molecules.


Assuntos
Doença de Alzheimer , Neurônios Colinérgicos , Células-Tronco Mesenquimais , Presenilina-1 , Cordão Umbilical , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Secretases da Proteína Precursora do Amiloide/metabolismo , Apoptose , Ácido Aspártico Endopeptidases/metabolismo , Cálcio/metabolismo , Neurônios Colinérgicos/metabolismo , Neurônios Colinérgicos/patologia , Humanos , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/patologia , Mutação , Estresse Oxidativo , Presenilina-1/genética , Presenilina-1/metabolismo , Cordão Umbilical/metabolismo , Cordão Umbilical/patologia , Proteínas tau/metabolismo
7.
Am J Physiol Heart Circ Physiol ; 319(1): H3-H12, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32412778

RESUMO

Heart failure (HF) is characterized by autonomic imbalance with sympathetic hyperactivity and loss of parasympathetic tone. Intracardiac ganglia (ICG) neurons represent the final common pathway for vagal innervation of the heart and strongly regulate cardiac functions. This study tests whether ICG cholinergic neuron activation mitigates the progression of cardiac dysfunction and reduces mortality that occurs in HF. HF was induced by transaortic constriction (TAC) in male transgenic Long-Evans rats expressing Cre recombinase within choline acetyltransferase (ChAT) neurons. ChAT neurons were selectively activated by expression and activation of excitatory designer receptors exclusively activated by designer receptors (DREADDs) by clozapine-N-oxide (TAC + treatment and sham-treated groups). Control animals expressed DREADDs but received saline (sham and TAC groups). A separate set of animals were telemetry instrumented to record blood pressure (BP) and heart rate (HR). Acute activation of ICG neurons resulted in robust reductions in BP (∼20 mmHg) and HR (∼100 beats/min). All groups of animals were subjected to weekly echocardiography and treadmill stress tests from 3 to 6 wk post-TAC/sham surgery. Activation of ICG cholinergic neurons reduced the left ventricular systolic dysfunction (reductions in ejection fraction, fractional shortening, stroke volume, and cardiac output) and cardiac autonomic dysfunction [reduced HR recovery (HRR) post peak effort] observed in TAC animals. Additionally, activation of ICG ChAT neurons reduced mortality by 30% compared with untreated TAC animals. These data suggest that ICG cholinergic neuron activation reduces cardiac dysfunction and improves survival in HF, indicating that ICG neuron activation could be a novel target for treating HF.NEW & NOTEWORTHY Intracardiac ganglia form the final common pathway for the parasympathetic innervation of the heart. This study has used a novel chemogenetic approach within transgenic ChAT-Cre rats [expressing only Cre-recombinase in choline acetyl transferase (ChAT) neurons] to selectively increase intracardiac cholinergic parasympathetic activity to the heart in a pressure overload-induced heart failure model. The findings from this study confirm that selective activation of intracardiac cholinergic neurons lessens cardiac dysfunction and mortality seen in heart failure, identifying a novel downstream cardiac-selective target for increasing cardioprotective parasympathetic activity in heart failure.


Assuntos
Neurônios Colinérgicos/fisiologia , Insuficiência Cardíaca/fisiopatologia , Coração/inervação , Função Ventricular , Animais , Sistema Nervoso Autônomo/fisiopatologia , Pressão Sanguínea , Colina O-Acetiltransferase/genética , Colina O-Acetiltransferase/metabolismo , Neurônios Colinérgicos/efeitos dos fármacos , Neurônios Colinérgicos/metabolismo , Clozapina/análogos & derivados , Clozapina/farmacologia , Coração/fisiopatologia , Insuficiência Cardíaca/etiologia , Frequência Cardíaca , Masculino , Ratos , Ratos Long-Evans , Obstrução do Fluxo Ventricular Externo/complicações
8.
Neuron ; 106(5): 855-869.e8, 2020 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-32240599

RESUMO

Predictive learning exerts a powerful influence over choice between instrumental actions. Nevertheless, how this learning is encoded in a sufficiently stable manner to influence choices that can occur much later in time is unclear. Here, we report that the basolateral amygdala (BLA) encodes predictive learning and establishes the memory necessary for future choices by driving the accumulation of delta-opioid receptors (DOPRs) on the somatic membrane of cholinergic interneurons in the nucleus accumbens shell (NAc-S). We found that the BLA controls DOPR accumulation via its influence on substance P release in the NAc-S, and that although DOPR accumulation is not necessary for predictive learning per se, it is necessary for the influence of this learning on later choice between actions. This study uncovers, therefore, a novel GPCR-based form of memory that is established by predictive learning and is necessary for such learning to guide the selection and execution of specific actions.


Assuntos
Complexo Nuclear Basolateral da Amígdala/fisiologia , Comportamento de Escolha/fisiologia , Neurônios Colinérgicos/metabolismo , Interneurônios/metabolismo , Memória/fisiologia , Núcleo Accumbens/metabolismo , Receptores Opioides delta/metabolismo , Substância P/metabolismo , Animais , Condicionamento Clássico/fisiologia , Condicionamento Operante/fisiologia , Aprendizagem/fisiologia , Camundongos , Receptores Acoplados a Proteínas-G/metabolismo , Estriado Ventral
9.
PLoS One ; 15(2): e0218643, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32017764

RESUMO

Postganglionic sympathetic neurons and satellite glial cells are the two major cell types of the peripheral sympathetic ganglia. Sympathetic neurons project to and provide neural control of peripheral organs and have been implicated in human disorders ranging from cardiovascular disease to peripheral neuropathies. Here we show that satellite glia regulate synaptic activity of cultured postnatal sympathetic neurons, providing evidence for local ganglionic control of sympathetic drive. In addition to modulating neuron-to-neuron cholinergic neurotransmission, satellite glia promote synapse formation and contribute to neuronal survival. Examination of the cellular architecture of the rat sympathetic ganglia in vivo shows this regulation of neuronal properties takes place during a developmental period in which neuronal morphology and density are actively changing and satellite glia enwrap sympathetic neuronal somata. Cultured satellite glia make and release factors that promote neuronal activity and that can partially rescue the neurons from cell death following nerve growth factor deprivation. Thus, satellite glia play an early and ongoing role within the postnatal sympathetic ganglia, expanding our understanding of the contributions of local and target-derived factors in the regulation of sympathetic neuron function.


Assuntos
Neurônios Colinérgicos/metabolismo , Gânglios Simpáticos/fisiologia , Neuroglia/metabolismo , Transmissão Sináptica , Animais , Células Cultivadas , Neurônios Colinérgicos/fisiologia , Feminino , Gânglios Simpáticos/citologia , Masculino , Neuroglia/fisiologia , Ratos , Ratos Sprague-Dawley
10.
Neural Netw ; 125: 10-18, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32070852

RESUMO

Recent findings suggest that acetylcholine mediates uncertainty-seeking behaviors through its projection to dopamine neurons - another neuromodulatory system known for its major role in reinforcement learning and decision-making. In this paper, we propose a leaky-integrate-and-fire model of this mechanism. It implements a softmax-like selection with an uncertainty bonus by a cholinergic drive to dopaminergic neurons, which in turn influence synaptic currents of downstream neurons. The model is able to reproduce experimental data in two decision-making tasks. It also predicts that: (i) in the absence of cholinergic input, dopaminergic activity would not correlate with uncertainty, and that (ii) the adaptive advantage brought by the implemented uncertainty-seeking mechanism is most useful when sources of reward are not highly uncertain. Moreover, this modeling work allows us to propose novel experiments which might shed new light on the role of acetylcholine in both random and directed exploration. Overall, this study contributes to a more comprehensive understanding of the role of the cholinergic system and, in particular, its involvement in decision-making.


Assuntos
Neurônios Colinérgicos/fisiologia , Tomada de Decisões , Neurônios Dopaminérgicos/fisiologia , Modelos Neurológicos , Redes Neurais de Computação , Incerteza , Acetilcolina/metabolismo , Animais , Neurônios Colinérgicos/metabolismo , Dopamina/fisiologia , Neurônios Dopaminérgicos/metabolismo , Humanos , Recompensa
11.
Sci Rep ; 10(1): 2542, 2020 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-32054879

RESUMO

The dopamine D5 receptor (D5R) is a Gαs-coupled dopamine receptor belonging to the dopamine D1-like receptor family. Together with the dopamine D2 receptor it is highly expressed in striatal cholinergic interneurons and therefore is poised to be a positive regulator of cholinergic activity in response to L-DOPA in the dopamine-depleted parkinsonian brain. Tonically active cholinergic interneurons become dysregulated during chronic L-DOPA administration and participate in the expression of L-DOPA induced dyskinesia. The molecular mechanisms involved in this process have not been elucidated, however a correlation between dyskinesia severity and pERK expression in cholinergic cells has been described. To better understand the function of the D5 receptor and how it affects cholinergic interneurons in L-DOPA induced dyskinesia, we used D5R knockout mice that were rendered parkinsonian by unilateral 6-OHDA injection. In the KO mice, expression of pERK was strongly reduced indicating that activation of these cells is at least in part driven by the D5 receptor. Similarly, pS6, another marker for the activity status of cholinergic interneurons was also reduced. However, mice lacking D5R exhibited slightly worsened locomotor performance in response to L-DOPA and enhanced LID scores. Our findings suggest that D5R can modulate L-DOPA induced dyskinesia and is a critical activator of CINs via pERK and pS6.


Assuntos
Dopamina/metabolismo , Discinesia Induzida por Medicamentos/genética , Levodopa/efeitos adversos , Receptores de Dopamina D5/genética , Animais , Neurônios Colinérgicos/efeitos dos fármacos , Neurônios Colinérgicos/metabolismo , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Modelos Animais de Doenças , Discinesia Induzida por Medicamentos/patologia , Humanos , Interneurônios/efeitos dos fármacos , Interneurônios/metabolismo , Sistema de Sinalização das MAP Quinases/genética , Camundongos , Camundongos Knockout , Oxidopamina/farmacologia , Doença de Parkinson/genética , Doença de Parkinson/patologia
12.
Artigo em Inglês | MEDLINE | ID: mdl-31975627

RESUMO

Cardiac sympathetic nerves undergo cholinergic transdifferentiation following reperfused myocardial infarction (MI), whereby the sympathetic nerves release both norepinephrine (NE) and acetylcholine (ACh). The functional electrophysiological consequences of post-MI transdifferentiation have never been explored. We performed MI or sham surgery in wild-type (WT) mice and mice in which choline acetyltransferase was deleted from adult noradrenergic neurons [knockout (KO)]. Electrophysiological activity was assessed with optical mapping of action potentials (AP) and intracellular Ca2+ transients (CaT) in innervated Langendorff-perfused hearts. KO MI hearts had similar NE content but reduced ACh content compared with WT MI hearts (0.360 ± 0.074 vs. 0.493 ± 0.087 pmol/mg; KO, n = 6; WT, n = 4; P < 0.05). KO MI hearts also had higher basal ex vivo heart rates versus WT MI hearts (328.5 ± 35.3 vs. 247.4 ± 62.4 beats/min; KO, n = 8; WT, n = 6; P < 0.05). AP duration at 80% repolarization was significantly shorter in the remote and border zones of KO MI versus WT MI hearts, whereas AP durations (APDs) were similar in infarct regions. This APD heterogeneity resulted in increased APD dispersion in the KO MI versus WT MI hearts (11.9 ± 2.7 vs. 8.2 ± 2.3 ms; KO, n = 8; WT, n = 6; P < 0.05), which was eliminated with atropine. CaT duration at 80% and CaT alternans magnitude were similar between groups both with and without sympathetic nerve stimulation. These results indicate that cholinergic transdifferentiation following MI prolongs APD in the remote and border zone and reduces APD heterogeneity.NEW & NOTEWORTHY Cardiac sympathetic neurons undergo cholinergic transdifferentiation following myocardial infarction; however, the electrophysiological effects of corelease of norepinephrine and acetylcholine (ACh) have never been assessed. Using a mouse model in which choline acetyltransferase was deleted from adult noradrenergic neurons and optical mapping of innervated hearts, we found that corelease of ACh reduces dispersion of action potential duration, which may be antiarrhythmic.


Assuntos
Potenciais de Ação/fisiologia , Sinalização do Cálcio/fisiologia , Transdiferenciação Celular/fisiologia , Neurônios Colinérgicos/metabolismo , Infarto do Miocárdio/fisiopatologia , Sistema Nervoso Simpático/metabolismo , Neurônios Adrenérgicos/metabolismo , Animais , Colina O-Acetiltransferase/genética , Colina O-Acetiltransferase/metabolismo , Modelos Animais de Doenças , Coração/inervação , Camundongos , Camundongos Knockout , Infarto do Miocárdio/metabolismo
13.
Cell Rep ; 30(4): 1178-1194.e3, 2020 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-31995757

RESUMO

To understand striatal function, it is essential to know the functional organization of the numerous inputs targeting the diverse population of striatal neurons. Using optogenetics, we activated terminals from ipsi- or contralateral primary somatosensory cortex (S1) or primary motor cortex (M1), or thalamus while obtaining simultaneous whole-cell recordings from pairs or triplets of striatal medium spiny neurons (MSNs) and adjacent interneurons. Ipsilateral corticostriatal projections provided stronger excitation to fast-spiking interneurons (FSIs) than to MSNs and only sparse and weak excitation to low threshold-spiking interneurons (LTSIs) and cholinergic interneurons (ChINs). Projections from contralateral M1 evoked the strongest responses in LTSIs but none in ChINs, whereas thalamus provided the strongest excitation to ChINs but none to LTSIs. In addition, inputs varied in their glutamate receptor composition and their short-term plasticity. Our data revealed a highly selective organization of excitatory striatal afferents, which is determined by both pre- and postsynaptic neuronal identity.


Assuntos
Neurônios Colinérgicos/fisiologia , Corpo Estriado/metabolismo , Interneurônios/fisiologia , Córtex Motor/fisiologia , Tálamo/fisiologia , Animais , Neurônios Colinérgicos/metabolismo , Corpo Estriado/citologia , Corpo Estriado/fisiologia , Feminino , Interneurônios/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Córtex Motor/efeitos da radiação , Vias Neurais/fisiologia , Plasticidade Neuronal/fisiologia , Optogenética , Técnicas de Patch-Clamp , Receptores de Glutamato/metabolismo , Córtex Somatossensorial/fisiologia , Sinapses/fisiologia , Tálamo/efeitos da radiação
14.
Mol Med Rep ; 21(3): 1172-1180, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31922229

RESUMO

Alzheimer's disease (AD) is the most prevalent age­related neurodegenerative disorder. It is featured by the progressive accumulation of ß­amyloid (Aß) plaques and neurofibrillary tangles. This can eventually lead to a decrease of cholinergic neurons in the basal forebrain. Stem cell transplantation is an effective treatment for neurodegenerative diseases. Previous studies have revealed that different types of stem or progenitor cells can mitigate cognition impairment in different Alzheimer's disease mouse models. However, understanding the underlying mechanisms of neural stem cell (NSC) therapies for AD requires further investigation. In the present study, the effects and the underlying mechanisms of the treatment of AD by NSCs are reported. The latter were labelled with the enhanced green fluorescent protein (EGFP) prior to implantation into the bilateral hippocampus of an amyloid precursor protein (APP)/presenilin 1 (PS1) transgenic (Tg) mouse model of AD. It was observed that the number of basal forebrain cholinergic neurons was restored and the expression of choline acetyltransferase (ChAT) protein was increased. Moreover, the levels of synaptophysin (SYP), postsynaptic density protein 95 (PSD­95) and microtubule­associated protein (MAP­2) were significantly increased in the hippocampus of NSC­treated AD mice. Notably, spatial learning and memory were both improved after transplantation of NSCs. In conclusion, the present study revealed that NSC transplantation improved learning and memory functions in an AD mouse model. This treatment allowed repairing of basal forebrain cholinergic neurons and increased the expression of the cognition­related proteins SYP, PSD­95 and MAP­2 in the hippocampus.


Assuntos
Doença de Alzheimer , Neurônios Colinérgicos , Aprendizagem , Memória , Células-Tronco Neurais , Presenilina-1 , Transplante de Células-Tronco , Sinapses , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/terapia , Amiloide/genética , Amiloide/metabolismo , Animais , Neurônios Colinérgicos/metabolismo , Neurônios Colinérgicos/patologia , Modelos Animais de Doenças , Camundongos , Camundongos Transgênicos , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Células-Tronco Neurais/transplante , Presenilina-1/biossíntese , Presenilina-1/genética , Sinapses/genética , Sinapses/metabolismo , Sinapses/patologia
15.
Alzheimers Res Ther ; 11(1): 110, 2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31881998

RESUMO

BACKGROUND: The persistence of adult hippocampal neurogenesis (AHN) is sharply decreased in Alzheimer's disease (AD). The neuropathologies of AD include the presence of amyloid-ß deposition in plaques, tau hyperphosphorylation in neurofibrillary tangles, and cholinergic system degeneration. The focused ultrasound (FUS)-mediated blood-brain barrier opening modulates tau hyperphosphorylation, the accumulation of amyloid-ß proteins, and increases in AHN. However, it remains unclear whether FUS can modulate AHN in cholinergic-deficient conditions. In this study, we investigated the effect of FUS on AHN in a cholinergic degeneration rat model of dementia. METHODS: Adult male Sprague-Dawley rats (n = 48; 200-250 g) were divided into control (phosphate-buffered saline injection), 192 IgG-saporin (SAP), and SAP+FUS groups; in the two latter groups, SAP was injected bilaterally into the lateral ventricle. We applied FUS to the bilateral hippocampus with microbubbles. Immunohistochemistry, enzyme-linked immunosorbent assay, immunoblotting, 5-bromo-2'-deoxyuridine labeling, an acetylcholinesterase assay, and the Morris water maze test were performed to assess choline acetyltransferase, acetylcholinesterase activity, brain-derived neurotrophic factor expression, neural proliferation, and spatial memory, respectively. Statistical significance of differences in between groups was calculated using one-way and two-way analyses of variance followed by Tukey's multiple comparison test to determine the individual and interactive effects of FUS on immunochemistry and behavioral analysis. P < 0.05 was considered significant. RESULTS: Cholinergic degeneration in rats significantly decreased the number of choline acetyltransferase neurons (P < 0.05) in the basal forebrain, as well as AHN and spatial memory function. Rats that underwent FUS-mediated brain-blood barrier opening exhibited significant increases in brain-derived neurotrophic factor (BDNF; P < 0.05), early growth response protein 1 (EGR1) (P < 0.01), AHN (P < 0.01), and acetylcholinesterase activity in the frontal cortex (P < 0.05) and hippocampus (P < 0.01) and crossing over (P < 0.01) the platform in the Morris water maze relative to the SAP group after sonication. CONCLUSIONS: FUS treatment increased AHN and improved spatial memory. This improvement was mediated by increased hippocampal BDNF and EGR1. FUS treatment may also restore AHN and protect against neurodegeneration, providing a potentially powerful therapeutic strategy for AD.


Assuntos
Neurônios Colinérgicos/patologia , Cognição/fisiologia , Demência/fisiopatologia , Hipocampo/fisiopatologia , Aprendizagem em Labirinto/fisiologia , Neurogênese/fisiologia , Ultrassonografia , Acetilcolinesterase/metabolismo , Animais , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Barreira Hematoencefálica/fisiopatologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proliferação de Células/fisiologia , Colina O-Acetiltransferase/metabolismo , Neurônios Colinérgicos/metabolismo , Demência/metabolismo , Demência/patologia , Hipocampo/metabolismo , Hipocampo/patologia , Masculino , Ratos , Ratos Sprague-Dawley , Memória Espacial/fisiologia
16.
Int J Mol Sci ; 20(22)2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31766245

RESUMO

The amygdala is a cerebral region whose function is compromised in temporal lobe epilepsy (TLE). Patients with TLE present cognitive and emotional dysfunctions, of which impairments in recognizing facial expressions have been clearly attributed to amygdala damage. However, damage to the amygdala has been scarcely addressed, with the majority of studies focusing on the hippocampus. The aim of this study was to evaluate epilepsy-related plasticity of cholinergic projections to the basolateral nucleus (BL) of the amygdala. Adult rats received kainic acid (KA) injections and developed status epilepticus. Weeks later, they showed spontaneous recurrent seizures documented by behavioral observations. Changes in cholinergic innervation of the BL were investigated by using an antibody against the vesicular acetylcholine transporter (VAChT). In KA-treated rats, it was found that (i) the BL shrunk to 25% of its original size (p < 0.01 vs. controls, Student's t-test), (ii) the density of vesicular acetylcholine transporter-immunoreactive (VAChT-IR) varicosities was unchanged, (iii) the volumes of VAChT-IR cell bodies projecting to the BL from the horizontal limb of the diagonal band of Broca, ventral pallidum, and subcommissural part of the substantia innominata were significantly increased (p < 0.05, Bonferroni correction). These results illustrate significant changes in the basal forebrain cholinergic cells projecting to the BL in the presence of spontaneous recurrent seizures.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Prosencéfalo Basal/fisiopatologia , Epilepsia do Lobo Temporal/fisiopatologia , Plasticidade Neuronal , Acetilcolina/metabolismo , Tonsila do Cerebelo/metabolismo , Animais , Prosencéfalo Basal/metabolismo , Neurônios Colinérgicos/metabolismo , Neurônios Colinérgicos/patologia , Modelos Animais de Doenças , Epilepsia do Lobo Temporal/induzido quimicamente , Epilepsia do Lobo Temporal/metabolismo , Ácido Caínico , Masculino , Ratos Wistar , Proteínas Vesiculares de Transporte de Acetilcolina/metabolismo
17.
BMC Genomics ; 20(1): 851, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31726970

RESUMO

BACKGROUND: Endogenous α-synuclein (α-Syn) is involved in many pathophysiological processes in the secondary injury stage after acute spinal cord injury (SCI), and the mechanism governing these functions has not been thoroughly elucidated to date. This research aims to characterize the effect of α-Syn knockdown on transcriptional levels after SCI and to determine the mechanisms underlying α-Syn activity based on RNA-seq. RESULT: The establishment of a rat model of lentiviral vector-mediated knockdown of α-Syn in Sprague-Dawley rats with T3 spinal cord contusion (LV_SCI group). The results of the RNA-seq analysis showed that there were 337 differentially expressed genes (DEGs) between the SCI group and the LV_SCI group, and 153 DEGs specific to LV_SCI between the (SCI vs LV_SCI) and (SCI vs CON) comparisons. The top 20 biological transition terms were identified by Gene ontology (GO) analysis. The Kyoto Gene and Genomic Encyclopedia (KEGG) analysis showed that the LV_SCI group significantly upregulated the cholinergic synaptic & nicotine addiction and the neuroactive ligand receptor interaction signaling pathway. Enriched chord analysis analyzes key genes. Further cluster analysis, gene and protein interaction network analysis and RT-qPCR results showed that Chrm2 and Chrnb2 together significantly in both pathways. The proliferation of muscarinic cholinergic receptor subtype 2 (Chrm2) and nicotinic cholinergic receptor subtype ß2 (Chrnb2), and the neurogenesis were elevated in the injury site of LV_SCI group by immunofluorescence. Further by subcellular localization, the LV_SCI group enhanced the expression of Chrnb2 at the cell membrane. CONCLUSION: Knockdown of α-Syn after SCI enhance motor function and promote neurogenesis probably through enhancing cholinergic signaling pathways and neuroreceptor interactions. This study not only further clarifies the understanding of the mechanism of knockdown of α-Syn on SCI but also helps to guide the treatment strategy for SCI.


Assuntos
Perfilação da Expressão Gênica , Traumatismos da Medula Espinal/genética , Transcriptoma , alfa-Sinucleína/genética , Animais , Animais Geneticamente Modificados , Biomarcadores , Neurônios Colinérgicos/metabolismo , Biologia Computacional/métodos , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Ontologia Genética , Redes Reguladoras de Genes , Neurogênese/genética , RNA Mensageiro , Ratos , Transdução de Sinais , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia
18.
Alzheimers Res Ther ; 11(1): 80, 2019 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-31511061

RESUMO

BACKGROUND: Up to 20% of patients with AD experience hallucinations. The pathological substrate is not known. Visual hallucinations (VH) are more common in dementia with Lewy bodies (DLB). In autopsy studies, up to 60% of patients with AD have concomitant Lewy body pathology. Decreased perfusion of the occipital lobe has been implicated in DLB patients with VH, and post-mortem studies point to both decreased cholinergic activity and reduced oxygenation of the occipital cortex in DLB. METHODS: We used biochemical methods to assess microvessel density (level of von Willebrand factor, a marker of endothelial cell content), ante-mortem oxygenation (vascular endothelial growth factor, a marker of tissue hypoxia; myelin-associated glycoprotein to proteolipid protein-1 ratio, a measure of tissue oxygenation relative to metabolic demand), cholinergic innervation (acetylcholinesterase and choline acetyltransferase), butyrylcholinesterase and insoluble α-synuclein content in the BA18 and BA19 occipital cortex obtained post-mortem from 23 AD patients who had experienced visual hallucinations, 19 AD patients without hallucinations, 19 DLB patients, and 36 controls. The cohorts were matched for age, gender and post-mortem interval. RESULTS: There was no evidence of reduced microvessel density, hypoperfusion or reduction in ChAT activity in AD with visual hallucinations. Acetylcholinesterase activity was reduced in both BA18 and BA19, in all 3 dementia groups, and the concentration was also reduced in BA19 in the DLB and AD without visual hallucinations groups. Insoluble α-synuclein was raised in the DLB group in both areas but not in AD either with or without visual hallucinations. CONCLUSIONS: Our results suggest that visual hallucinations in AD are associated with cholinergic denervation rather than chronic hypoperfusion or α-synuclein accumulation in visual processing areas of the occipital cortex.


Assuntos
Doença de Alzheimer/patologia , Neurônios Colinérgicos/patologia , Alucinações/patologia , Córtex Visual/patologia , Acetilcolina/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/complicações , Doença de Alzheimer/metabolismo , Neurônios Colinérgicos/metabolismo , Feminino , Alucinações/etiologia , Alucinações/metabolismo , Humanos , Doença por Corpos de Lewy/complicações , Doença por Corpos de Lewy/metabolismo , Doença por Corpos de Lewy/patologia , Masculino , Córtex Visual/irrigação sanguínea , Córtex Visual/metabolismo , Vias Visuais/metabolismo , Vias Visuais/patologia
19.
eNeuro ; 6(4)2019.
Artigo em Inglês | MEDLINE | ID: mdl-31366590

RESUMO

Vesicular glutamate transporters (VGLUTs) mediate the synaptic uptake of glutamate from the cytosol into synaptic vesicles and are considered unambiguous neurochemical markers of glutamate neurons. However, many neurons not classically thought of as glutamatergic also express a VGLUT and co-release glutamate. Using a genetic fate-mapping strategy we found that most cholinergic neurons in the mouse mesopontine tegmentum express VGLUT2 at some point during development, including the pedunculopontine tegmental nucleus (PPTg), laterodorsal tegmental nucleus, and parabigeminal nucleus (PBG), but not the oculomotor nucleus. In contrast, very few of these cholinergic neurons displayed evidence of vesicular GABA transporter expression. Using multiplex fluorescent in situ hybridization, we determined that only PBG cholinergic neurons are also predominantly positive for VGLUT2 mRNA in the adult, with only small numbers of PPTg cholinergic neurons overlapping with VGLUT2 mRNA. Using Cre-dependent viral vectors we confirm these in situ hybridization data, and demonstrate projection patterns of cholinergic and glutamatergic populations. These results demonstrate that most mesopontine cholinergic neurons may transiently express VGLUT2, but that a large majority of PBG neurons retain VGLUT2 expression throughout adulthood, and support a growing body of literature indicating that distinct cholinergic populations have differing potential for GABA or glutamate co-release.


Assuntos
Neurônios Colinérgicos/metabolismo , Mesencéfalo/metabolismo , Proteína Vesicular 2 de Transporte de Glutamato/metabolismo , Animais , Feminino , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios/metabolismo , Núcleo Tegmental Pedunculopontino/metabolismo , RNA Mensageiro/metabolismo
20.
Brain Struct Funct ; 224(8): 2703-2716, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31375982

RESUMO

The greater part of the striatum is composed of striosomes and matrix compartments, but we recently demonstrated the presence of a region that has a distinct structural organization in the ventral half of the mouse caudal striatum (Miyamoto et al. in Brain Struct Funct 223:4275-4291, 2018). This region, termed the tri-laminar part based upon its differential immunoreactivities for substance P and enkephalin, consists of medial, intermediate, and lateral divisions. In this study, we quantitatively analyzed the distributions of both projection neurons and interneurons in each division using immunohistochemistry. Two types of projection neurons expressing either the dopamine D1 receptor (D1R) or D2 receptor (D2R) showed complementary distributions throughout the tri-laminar part, but the proportions significantly differed among the three divisions. The proportion of D1R-expressing neurons in the medial, intermediate, and lateral divisions was 88.6 ± 8.2% (651 cells from 3 mice), 14.7 ± 3.8% (1025 cells), and 49.3 ± 4.5% (873 cells), respectively. The intermediate division was further characterized by poor innervation of tyrosine hydroxylase immunoreactive axons. The numerical density of choline acetyltransferase immunoreactive neurons differed among the three divisions following the order from the medial to lateral divisions. In contrast, PV-positive somata were distributed throughout all three divisions at a constant density. Two types of GABAergic interneurons labeled for nitric oxide synthase and calretinin showed the highest cell density in the medial division. The present results characterize the three divisions of the mouse caudal striatum as distinct structures, which will facilitate studies of novel functional loops in the basal ganglia.


Assuntos
Neurônios Colinérgicos/citologia , Corpo Estriado/citologia , Neurônios Dopaminérgicos/citologia , Neurônios GABAérgicos/citologia , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo , Animais , Axônios , Neurônios Colinérgicos/metabolismo , Corpo Estriado/metabolismo , Neurônios Dopaminérgicos/metabolismo , Neurônios GABAérgicos/metabolismo , Interneurônios/citologia , Interneurônios/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
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