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1.
Nat Commun ; 12(1): 1142, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33602941

RESUMO

Negative symptoms in schizophrenia strongly contribute to poor functional outcomes, however its pathogenesis is still unclear. Here, we found that histamine H1 receptor (H1R) expression in basal forebrain (BF) cholinergic neurons was decreased in patients with schizophrenia having negative symptoms. Deletion of H1R gene in cholinergic neurons in mice resulted in functional deficiency of cholinergic projections from the BF to the prefrontal cortex and in the formation of sensorimotor gating deficit, social impairment and anhedonia-like behavior. These behavioral deficits can be rescued by re-expressing H1R or by chemogenetic activation of cholinergic neurons in the BF. Direct chemogenetic inhibition of BF cholinergic neurons produced such behavioral deficits and also increased the susceptibility to hyperlocomotion. Our results suggest that the H1R deficiency in BF cholinergic neurons is critical for sensorimotor gating deficit, social impairments and anhedonia-like behavior. This finding may help to understand the genetic and biochemical bases of negative symptoms in schizophrenia.


Assuntos
Neurônios Colinérgicos/metabolismo , Receptores Histamínicos H1/metabolismo , Filtro Sensorial , Comportamento Social , Anedonia/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Colina O-Acetiltransferase/metabolismo , Disfunção Cognitiva/complicações , Maleato de Dizocilpina/farmacologia , Feminino , Integrases/metabolismo , Locomoção/efeitos dos fármacos , Masculino , Camundongos , Camundongos Transgênicos , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/patologia , Esquizofrenia/patologia
2.
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
3.
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
4.
Life Sci ; 256: 117975, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32565251

RESUMO

Our goal is to understand how loss of circulating estrogens and estrogen replacement affect brain physiology and function, particularly in brain regions involved in cognitive processes. We recently conducted a large metabolomics study characterizing the effects of rodent models of menopause and treatment with estrogen receptor (ER) agonists on neurochemical targets in hippocampus, frontal cortex, and striatum. Here we characterize effects on levels of several key enzymes involved in glucose utilization and energy production, specifically phosphofructokinase, glyceraldehyde 3-phosphate dehydrogenase, and pyruvate dehydrogenase. We also evaluated effects on levels of ß-actin and α-tubulin, choline acetyltransferase (ChAT) activity, and levels of ATP citrate lyase. All experiments were conducted in young adult rats. Experiment 1 compared the effects of ovariectomy (OVX), a model of surgical menopause, and 4-vinylcyclohexene diepoxide (VCD)-treatments, a model of transitional menopause, with tissues collected at proestrus and at diestrus. Experiment 2 used a separate cohort of rats to evaluate the same targets in OVX and VCD-treated rats treated with estradiol or with selective ER agonists. Differences in the expression of metabolic enzymes between cycling animals and models of surgical and transitional menopause were detected. These differences were model-, region- and time- dependent, and were modulated by selective ER agonists. Collectively, the findings demonstrate that loss of ovarian function and ER agonist treatments have differing effects in OVX vs. VCD-treated rats. Differences may help to explain differences in the effects of estrogen treatments on brain function and cognition in women who have experienced surgical vs. transitional menopause.


Assuntos
Acetilcoenzima A/metabolismo , Encéfalo/metabolismo , Colina O-Acetiltransferase/metabolismo , Estrogênios/farmacologia , Menopausa/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Cicloexenos/toxicidade , Estradiol/sangue , Feminino , Menopausa/efeitos dos fármacos , Ovariectomia/efeitos adversos , Ratos , Ratos Sprague-Dawley , Compostos de Vinila/toxicidade
5.
Nature ; 581(7807): 204-208, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32405000

RESUMO

It has been speculated that brain activities might directly control adaptive immune responses in lymphoid organs, although there is little evidence for this. Here we show that splenic denervation in mice specifically compromises the formation of plasma cells during a T cell-dependent but not T cell-independent immune response. Splenic nerve activity enhances plasma cell production in a manner that requires B-cell responsiveness to acetylcholine mediated by the α9 nicotinic receptor, and T cells that express choline acetyl transferase1,2 probably act as a relay between the noradrenergic nerve and acetylcholine-responding B cells. We show that neurons in the central nucleus of the amygdala (CeA) and the paraventricular nucleus (PVN) that express corticotropin-releasing hormone (CRH) are connected to the splenic nerve; ablation or pharmacogenetic inhibition of these neurons reduces plasma cell formation, whereas pharmacogenetic activation of these neurons increases plasma cell abundance after immunization. In a newly developed behaviour regimen, mice are made to stand on an elevated platform, leading to activation of CeA and PVN CRH neurons and increased plasma cell formation. In immunized mice, the elevated platform regimen induces an increase in antigen-specific IgG antibodies in a manner that depends on CRH neurons in the CeA and PVN, an intact splenic nerve, and B cell expression of the α9 acetylcholine receptor. By identifying a specific brain-spleen neural connection that autonomically enhances humoral responses and demonstrating immune stimulation by a bodily behaviour, our study reveals brain control of adaptive immunity and suggests the possibility to enhance immunocompetency by behavioural intervention.


Assuntos
Comportamento Animal/fisiologia , Encéfalo/fisiologia , Imunidade Humoral/imunologia , Baço/imunologia , Baço/inervação , Acetilcolina/metabolismo , Acetilcolina/farmacologia , Neurônios Adrenérgicos/metabolismo , Tonsila do Cerebelo/citologia , Tonsila do Cerebelo/efeitos dos fármacos , Tonsila do Cerebelo/metabolismo , Animais , Encéfalo/citologia , Encéfalo/efeitos dos fármacos , Colina O-Acetiltransferase/metabolismo , Hormônio Liberador da Corticotropina/metabolismo , Hemocianinas/imunologia , Imunoglobulina G/imunologia , Ativação Linfocitária , Masculino , Camundongos , Núcleo Hipotalâmico Paraventricular/citologia , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , Núcleo Hipotalâmico Paraventricular/metabolismo , Plasmócitos/citologia , Plasmócitos/efeitos dos fármacos , Plasmócitos/imunologia , Receptores Nicotínicos/deficiência , Receptores Nicotínicos/metabolismo , Baço/citologia , Baço/efeitos dos fármacos , Estresse Psicológico/imunologia , Estresse Psicológico/metabolismo , Linfócitos T/imunologia
6.
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
7.
Endocrinology ; 161(4)2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32166324

RESUMO

Genetic research has revealed pro-opiomelanocortin (POMC) to be a fundamental regulator of energy balance and body weight in mammals. Within the brain, POMC is primarily expressed in the arcuate nucleus of the hypothalamus (ARC), while a smaller population exists in the brainstem nucleus of the solitary tract (POMCNTS). We performed a neurochemical characterization of this understudied population of POMC cells using transgenic mice expressing green fluorescent protein (eGFP) under the control of a POMC promoter/enhancer (PomceGFP). Expression of endogenous Pomc mRNA in the nucleus of the solitary tract (NTS) PomceGFP cells was confirmed using fluorescence-activating cell sorting (FACS) followed by quantitative PCR. In situ hybridization histochemistry of endogenous Pomc mRNA and immunohistochemical analysis of eGFP revealed that POMC is primarily localized within the caudal NTS. Neurochemical analysis indicated that POMCNTS is not co-expressed with tyrosine hydroxylase (TH), glucagon-like peptide 1 (GLP-1), cholecystokinin (CCK), brain-derived neurotrophic factor (BDNF), nesfatin, nitric oxide synthase 1 (nNOS), seipin, or choline acetyltransferase (ChAT) cells, whereas 100% of POMCNTS is co-expressed with transcription factor paired-like homeobox2b (Phox2b). We observed that 20% of POMCNTS cells express receptors for adipocyte hormone leptin (LepRbs) using a PomceGFP:LepRbCre:tdTOM double-reporter line. Elevations in endogenous or exogenous leptin levels increased the in vivo activity (c-FOS) of a small subset of POMCNTS cells. Using ex vivo slice electrophysiology, we observed that this effect of leptin on POMCNTS cell activity is postsynaptic. These findings reveal that a subset of POMCNTS cells are responsive to both changes in energy status and the adipocyte hormone leptin, findings of relevance to the neurobiology of obesity.


Assuntos
Tronco Encefálico/metabolismo , Neurônios/metabolismo , Pró-Opiomelanocortina/metabolismo , Receptores para Leptina/metabolismo , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Colecistocinina/metabolismo , Colina O-Acetiltransferase/metabolismo , Subunidades gama da Proteína de Ligação ao GTP/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Camundongos , Camundongos Transgênicos , Óxido Nítrico Sintase Tipo I/metabolismo , Nucleobindinas/metabolismo , Regiões Promotoras Genéticas , Receptores para Leptina/genética , Tirosina 3-Mono-Oxigenase/metabolismo
8.
Gene ; 744: 144616, 2020 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-32222531

RESUMO

AIM: The purpose of this study was to investigate the possible effects of Myrtus communis subsp. communis (MC) on cognitive impairment in ovariectomized diabetic rats. MATERIAL AND METHOD: Female Sprague-Dawley rats were divided into 5 groups consisting of 15 rats each; Control (C), Diabetes (D), Ovariectomy and diabetes (OVX + D), Ovariectomy, diabetes and donepezil (OVX + D + Don), Ovariectomy, diabetes and Myrtus communis subsp. communis (OVX + D + MC). Blood glucose measurements were made at the beginning and end of the experiments. The animals underwent the novel object recognition test (NORT) and their performance was evaluated. In hippocampal tissues; amyloid beta (Aß) and neprilysin levels, acetylcholinesterase (AChE), and choline acetyltransferase (ChAT) activities, polysialylated neural cell adhesion molecule (PSA-NCAM), α7 subunit of neuronal nicotinic acetylcholine receptor (α7-nAChR) and brain derived neurotrophic factor (BDNF) gene expressions were examined. RESULTS: Animals with ovariectomy and diabetes showed increased levels of blood glucose, AChE activity and Aß levels, and decreased neprilysin levels, ChAT activity, α7-nAChR, PSA-NCAM and BDNF gene expressions in parallel with a decrease in NORT performance score. On the other hand, in the MC-treated OVX + D group, there was a significant decrease observed in blood glucose levels and AChE activities while there was improvement in NORT performances and an increase in hippocampal ChAT activity, neprilysin levels, α7-nAChR, PSA-NCAM and BDNF expressions. CONCLUSION: These results suggest that MC extract could improve cognitive and neuronal functions with its anticholinesterase and antihyperglycemic properties.


Assuntos
Cognição/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Myrtus , Fitoterapia , Acetilcolinesterase/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Glicemia/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Colina O-Acetiltransferase/metabolismo , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/psicologia , Feminino , Hipocampo/metabolismo , Neprilisina/metabolismo , Molécula L1 de Adesão de Célula Nervosa/genética , Molécula L1 de Adesão de Célula Nervosa/metabolismo , Ovariectomia , Extratos Vegetais/uso terapêutico , Ratos Sprague-Dawley , Ácidos Siálicos/genética , Ácidos Siálicos/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/genética , Receptor Nicotínico de Acetilcolina alfa7/metabolismo
9.
Invest Ophthalmol Vis Sci ; 61(2): 14, 2020 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-32049344

RESUMO

Purpose: Experimental access to specific cell subtypes is essential for deciphering the complexity of retinal networks. Here, we characterized the selective labeling, caused by ectopic transgene expression, of two atypical retinal neurons in the ChAT-Channelrhodopsin-2 (ChR2)-EYFP mouse. Methods: Retinal sections and flat-mounts were prepared for double-staining immunohistochemistry with antibodies against EYFP and various neuronal markers. Sagittal/coronal brain slices were made to visualize EYFP signals in central nuclei. Whole-cell recordings were conducted to test the functionality of ChR2. Results: Two populations of EYFP-positive retinal cells were observed. The inner nuclear layer (INL)-located one (type I cell) distributed regularly throughout the entire retina, whereas the ganglion cell layer (GCL)-residing one (type II cell) was restricted ventrally. None of them was cholinergic, as evidenced by the complete absence of ChAT immunoreactivity. Type I cells were immunolabeled by the amacrine marker syntaxin. However, the vast majority of them were neither positive to GABA/GAD65, nor to GlyT1/glycine, suggesting that they were non-GABAergic non-glycinergic amacrine cells (nGnG ACs), which was confirmed by double-labeling with the nGnG AC marker PPP1R17. Type II cells were immunopositive to melanopsin, but not to Brn3a or Brn3b. They possessed dendrites stratifying in the outermost inner plexiform layer (IPL) and axons projecting to the suprachiasmatic nucleus (SCN) rather than the olivary pretectal nucleus (OPN), suggesting that they belonged to a Brn3b-negative subset of M1-type intrinsically photosensitive retinal ganglion cells (ipRGCs). Glutamatergic transmission-independent photocurrents were elicited in EYFP-positive cells, indicating the functional expression of ChR2. Conclusions: The ChAT-ChR2-EYFP retina exhibits ectopic, but functional, transgene expression in nGnG ACs and SCN-innervating M1 ipRGCs, thus providing an ideal tool to achieve efficient labeling and optogenetic manipulation of these cells.


Assuntos
Células Amácrinas/metabolismo , Proteínas de Homeodomínio/metabolismo , Células Ganglionares da Retina/metabolismo , Fator de Transcrição Brn-3B/metabolismo , Transgenes/fisiologia , Animais , Channelrhodopsins/metabolismo , Colina O-Acetiltransferase/metabolismo , Feminino , Expressão Gênica , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Transgenes/genética
10.
PLoS Biol ; 18(2): e3000613, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32027647

RESUMO

Cortical interneurons expressing vasoactive intestinal polypeptide (VIP) and choline acetyltransferase (ChAT) are sparsely distributed throughout the neocortex, constituting only 0.5% of its neuronal population. The co-expression of VIP and ChAT suggests that these VIP/ChAT interneurons (VChIs) can release both γ-aminobutyric acid (GABA) and acetylcholine (ACh). In vitro physiological studies quantified the response properties and local connectivity patterns of the VChIs; however, the function of VChIs has not been explored in vivo. To study the role of VChIs in cortical network dynamics and their long-range connectivity pattern, we used in vivo electrophysiology and rabies virus tracing in the barrel cortex of mice. We found that VChIs have a low spontaneous spiking rate (approximately 1 spike/s) in the barrel cortex of anesthetized mice; nevertheless, they responded with higher fidelity to whisker stimulation than the neighboring layer 2/3 pyramidal neurons (Pyrs). Analysis of long-range inputs to VChIs with monosynaptic rabies virus tracing revealed that direct thalamic projections are a significant input source to these cells. Optogenetic activation of VChIs in the barrel cortex of awake mice suppresses the sensory responses of excitatory neurons in intermediate amplitudes of whisker deflections while increasing the evoked spike latency. The effect of VChI activation on the response was similar for both high-whisking (HW) and low-whisking (LW) conditions. Our findings demonstrate that, despite their sparsity, VChIs can effectively modulate sensory processing in the cortical microcircuit.


Assuntos
Colina O-Acetiltransferase/metabolismo , Interneurônios/fisiologia , Córtex Somatossensorial/citologia , Peptídeo Intestinal Vasoativo/metabolismo , Animais , Colina O-Acetiltransferase/genética , Potenciais Evocados , Potenciais Pós-Sinápticos Inibidores , Integrases/genética , Interneurônios/metabolismo , Camundongos , Camundongos Transgênicos , Vias Neurais , Neurônios/metabolismo , Neurônios/fisiologia , Optogenética , Córtex Somatossensorial/metabolismo , Peptídeo Intestinal Vasoativo/genética , Núcleos Ventrais do Tálamo/metabolismo , Vibrissas
11.
Am J Physiol Heart Circ Physiol ; 318(3): H558-H565, 2020 03 01.
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
12.
Arch Oral Biol ; 109: 104571, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31586907

RESUMO

OBJECTIVE: To study the innervation of the major sublingual gland by means of immunohistochemistry. DESIGN: Bioptic and autoptic specimens of the major sublingual gland of humans were examined for the presence of immunoreactivity to tyrosine hydroxylase and dopamine-ß-hydroxylase, on one hand, and choline acetyltransferase, on the other, to indicate adrenergic and cholinergic nerves, respectively. RESULTS: Acini and ducts were supplied by both divisions of the autonomic nervous system. CONCLUSIONS: Mucous and seromucous cells of the human major sublingual glands may respond with secretion not only to parasympathetic activity but also to sympathetic activity. The major sublingual gland is therefore a potential contributor to the mucin secretion recently reported in the literature in response to high sympathetic activity during physical exercise.


Assuntos
Colina O-Acetiltransferase/metabolismo , Dopamina beta-Hidroxilase/metabolismo , Glândula Sublingual/enzimologia , Tirosina 3-Mono-Oxigenase/metabolismo , Adulto , Idoso , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade
13.
Int J Neurosci ; 130(3): 262-269, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31544572

RESUMO

Aim of the study: High-fat diet (HFD) consumption and insufficient vitamin D levels are globally increasing phenomena. The present study assessed the effect of chronic HFD feeding with and without vitamin D supplementation on recognition memory and prefrontal cortex expression of choline acetyltransferase (CAT) and acetylcholinesterase (Achase).Materials and methods: Forty male Wistar rats were subjected to four dietary regimens (n = 10); control diet (10% fat), control + vitamin D3, high-fat diet (HFD 45% fat) and HFD + vitamin D3 for 6 months. Rats were tested for the novel object recognition test, and their prefrontal cortices were assessed for expression of CAT and Achase.Results: Recognition memory was impaired in HFD-fed rats compared to control rats as evidenced by significantly decreased discrimination index in the novel object recognition test. Moreover, CAT expression was significantly decreased while Achase expression was significantly increased in the prefrontal cortex of HFD-fed rats. Vitamin D3 supplementation with HFD significantly increased the exploration of the novel object and the discrimination index and attenuated the alterations in the prefrontal cortex CAT and Achase expression.Conclusions: The present findings support the potential effect of vitamin D on recognition memory and cholinergic transmission in the prefrontal cortex and add to the pathophysiology of HFD consumption.


Assuntos
Acetilcolinesterase/metabolismo , Comportamento Animal/efeitos dos fármacos , Colecalciferol/farmacologia , Colina O-Acetiltransferase/metabolismo , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia , Dieta Hiperlipídica/efeitos adversos , Memória Episódica , Córtex Pré-Frontal/enzimologia , Reconhecimento Psicológico/efeitos dos fármacos , Animais , Colecalciferol/administração & dosagem , Suplementos Nutricionais , Modelos Animais de Doenças , Masculino , Ratos , Ratos Wistar
14.
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
15.
Invest Ophthalmol Vis Sci ; 60(14): 4759-4773, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31738824

RESUMO

Purpose: Reaggregates from E6 embryonic chicken retina exhibit areas corresponding to an inner plexiform layer (IPL), which presents an ideal in vitro model to test conditions and constraints of cholinergic and glutamatergic network formation, providing a basis for retinal tissue engineering. Here, we show that ipl formation is regulated by cholinergic starburst amacrine cells (SACs), a glial scaffold and by L-glutamate. Methods: Rosetted spheroids were cultured in absence or presence of 0.2 to 0.4 mM L-glutamate and analyzed by immuno- and enzyme histochemistry, proliferation, and apoptosis assays. Results: After 2 days in vitro (div), ipl formation was announced by acetylcholinesterase+ (AChE) and choline acetyltransferase+ (ChAT) cells. Individual vimentin+ or transitin+ Müller glial cell precursors (MCPs) in ipl centers coexpressed ChAT. Comparable to in vivo, pairwise arranged ChAT+ SACs formed two laminar subbands. Projections of calretinin+ amacrine cells (ACs) into ipl associated with MCP processes. In L-glutamate-, or NMDA-treated spheroids ipls were disrupted, including loss of SACs and MCs; coincubation with NMDA receptor inhibitor MK-801 prevented these effects. Also, many Pax6+ cells, comprising most ACs, were lost, while rho4D2+ rod photoreceptors were increased. Cell proliferation was slightly increased, while apoptosis remained unaffected. Conclusions: This demonstrated: (1) a far-advanced differentiation of an IPL in retinal spheroids, as never described before; (2) ipl sublamination was initiated by cholinergic precursor cells, which-functioning as "ipl founder cells"-(3) gave rise to neurons and glial cells; (4) these SACs and MCPs together organized ipl formation; and (5) this process was counteracted by NMDA-dependent glutamate actions.


Assuntos
Diferenciação Celular/fisiologia , Colinérgicos/farmacologia , Células Ependimogliais/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Retina/embriologia , Transdução de Sinais/fisiologia , Esferoides Celulares/efeitos dos fármacos , Acetilcolinesterase/metabolismo , Animais , Proliferação de Células/fisiologia , Células Cultivadas , Embrião de Galinha , Colina O-Acetiltransferase/metabolismo , Crioultramicrotomia , Ácido Glutâmico/farmacologia , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Neurônios Retinianos/citologia , Esferoides Celulares/metabolismo , Fixação de Tecidos , Vimentina/metabolismo
16.
Nat Commun ; 10(1): 5280, 2019 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-31754098

RESUMO

Neocortical choline acetyltransferase (ChAT)-expressing interneurons are a subclass of vasoactive intestinal peptide (ChAT-VIP) neurons of which circuit and behavioural function are unknown. Here, we show that ChAT-VIP neurons directly excite neighbouring neurons in several layers through fast synaptic transmission of acetylcholine (ACh) in rodent medial prefrontal cortex (mPFC). Both interneurons in layers (L)1-3 as well as pyramidal neurons in L2/3 and L6 receive direct inputs from ChAT-VIP neurons mediated by fast cholinergic transmission. A fraction (10-20%) of postsynaptic neurons that received cholinergic input from ChAT-VIP interneurons also received GABAergic input from these neurons. In contrast to regular VIP interneurons, ChAT-VIP neurons did not disinhibit pyramidal neurons. Finally, we show that activity of these neurons is relevant for behaviour and they control attention behaviour distinctly from basal forebrain ACh inputs. Thus, ChAT-VIP neurons are a local source of cortical ACh that directly excite neurons throughout cortical layers and contribute to attention.


Assuntos
Atenção/efeitos dos fármacos , Colinérgicos/farmacologia , Interneurônios/fisiologia , Córtex Pré-Frontal/metabolismo , Acetilcolina/farmacologia , Animais , Atenção/fisiologia , Córtex Cerebral/citologia , Córtex Cerebral/metabolismo , Colina O-Acetiltransferase/metabolismo , Feminino , Interneurônios/efeitos dos fármacos , Interneurônios/metabolismo , Masculino , Camundongos da Linhagem 129 , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/fisiologia , Córtex Pré-Frontal/citologia , Ratos , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia , Peptídeo Intestinal Vasoativo/metabolismo
17.
J Chem Neuroanat ; 102: 101701, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31585148

RESUMO

The cholinergic system plays an important role in brain homeostasis and interacts with the neuropeptidergic systems, and the functional relationships between both systems are well known. However, in the brainstem the possible physiological interactions between neurokinins and acetylcholine are unknown, although both substances have been detected in the same brainstem nuclei and have been implicated in similar functions controlled from brainstem regions such as some cranial motor nuclei. The aim of this work is to determine whether these possible physiological interactions might have a neuroanatomical basis by means of the double immunohistochemical detection of neurokinins (NK) and the enzyme choline acetyl-transferase (ChAT) in the human brainstem. No double-labelled structures were detected, although both NK and ChAT were observed in cell bodies and fibers of the same brainstem nuclei. The distribution of immunoreactive fibers is widespread, and NK and ChAT were observed in several motor cranial nerves as well as in the substantia nigra. The results obtained in the present work provide a neuroanatomical basis for possible physiological interactions between NK and ChAT that may be carried out by volume-transmission mechanisms. These interactions might participate in motor regulation or in limbic pathways as well as influence on other neurotransmitter systems such as the dopaminergic system.


Assuntos
Acetilcolina/metabolismo , Tronco Encefálico/metabolismo , Colina O-Acetiltransferase/metabolismo , Taquicininas/metabolismo , Idoso de 80 Anos ou mais , Feminino , Humanos , Imuno-Histoquímica , Masculino , Neurônios/metabolismo
18.
Int J Dev Neurosci ; 78: 222-226, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31589917

RESUMO

Maple Syrup Urine Disease (MSUD) is an autosomal recessive inherited disorder, caused by a deficiency on branched chain α-ketoacid dehydrogenase complex activity, resulting in accumulation of branched-chain amino acids (BCAA) (e.g. leucine). The treatment of MSDU patients increases survival time and quality of life. Thus, nowadays there are a crescent number of adolescents and adults with MSUD. Relevant studies have been reported behavioral alterations in these patients, i.e. high risk of chronic neuropsychiatric problems, such as attention deficit disorder, depression and anxiety. Moreover, MSUD is associated to neurotransmitters deficiency. Herein, we aimed to investigate whether the toxicity of leucine is associated to anxiety-like behavioral, using zebrafish acutely exposed to leucine as experimental model of MSUD. In addition, we evaluated the effects of high levels of leucine in the acetylcholinesterase (AChE) and choline acetyltransferase (ChAT) activities, components of cholinergic neurotransmission system. Young zebrafish were exposed to 2 mM and 5 mM concentration of leucine for 24 h. After that, the animals were submitted to the Novel Tank test, having the brain collected to enzymatic determination. The exposure to both concentrations of leucine caused behavioral and brain cholinergic activity alterations in young zebrafish, indicating an anxiety-like behavior and cholinergic dysfunction. Therefore, this animal could be considered a promising organism to study the BCAA neurotoxic effects, which could help to a better comprehension of the behavioral and neurochemical alterations present in patients with MSUD.


Assuntos
Acetilcolinesterase/metabolismo , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Colina O-Acetiltransferase/metabolismo , Leucina/farmacologia , Doença da Urina de Xarope de Bordo/metabolismo , Animais , Encéfalo/metabolismo , Modelos Animais de Doenças , Peixe-Zebra
19.
Int J Mol Sci ; 20(21)2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31661900

RESUMO

The cholinergic efferent network from the medial septal nucleus to the hippocampus has an important role in learning and memory processes. This cholinergic projection can generate theta oscillations in the hippocampus to efficiently encode novel information. Hippocampal cholinergic neurostimulating peptide (HCNP) induces acetylcholine synthesis in medial septal nuclei. HCNP is processed from the N-terminal region of a 186 amino acid, 21 kD HCNP precursor protein called HCNP-pp (also known as Raf kinase inhibitory protein (RKIP) and phosphatidylethanolamine-binding protein 1 (PEBP1)). In this study, we generated HCNP-pp knockout (KO) mice and assessed their cholinergic septo-hippocampal projection, local field potentials in CA1, and behavioral phenotypes. No significant behavioral phenotype was observed in HCNP-pp KO mice. However, theta power in the CA1 of HCNP-pp KO mice was significantly reduced because of fewer cholineacetyltransferase-positive axons in the CA1 stratum oriens. These observations indicated disruption of cholinergic activity in the septo-hippocampal network. Our study demonstrates that HCNP may be a cholinergic regulator in the septo-hippocampal network.


Assuntos
Região CA1 Hipocampal/fisiologia , Neurônios Colinérgicos/fisiologia , Neuropeptídeos/fisiologia , Proteína de Ligação a Fosfatidiletanolamina/genética , Acetilcolina/metabolismo , Animais , Axônios/metabolismo , Escala de Avaliação Comportamental , Região CA1 Hipocampal/citologia , Região CA1 Hipocampal/metabolismo , Colina O-Acetiltransferase/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neuropeptídeos/metabolismo , Proteína de Ligação a Fosfatidiletanolamina/metabolismo
20.
Pharmacol Biochem Behav ; 186: 172790, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31499145

RESUMO

Binge drinking is characterized by excessive alcohol consumption in a short period of time and is associated with a poor quality of life. Zebrafish are commonly used to investigate neurochemical, behavioral, and genetic parameters associated with ethanol (EtOH) exposure. However, few studies have used zebrafish as a model to investigate binge EtOH exposure. In order to elucidate the potential neurobehavioral impairments evoked by binge EtOH exposure in zebrafish, animals were immersed in 1.4% EtOH for 30 min three consecutive times with intervals of one week. Neurobehavioral parameters were analyzed immediately following the third exposure, as well as 2 and 9 days later. Brain choline acetyltransferase (ChAT) and acetylcholinesterase (AChE) activities were reduced 9 days after the treatment. Thiobarbituric acid-reactive species and dichlorodihydrofluorescein levels were increased immediately after the treatment, but both returned to normal levels 2 days after the treatment. Catalase and glutathione reductase were impaired 2 and 9 days after the treatment. No alteration was observed in superoxide dismutase and glutathione peroxidase activities. EtOH treatment did not alter brain expression of inflammatory genes such as il-1ß, il-10, and tnf-α. Zebrafish displayed anxiolytic-like behavior immediately after the last exposure, though there was no behavioral alteration observed 9 days after the treatment. Therefore, binge EtOH exposure in zebrafish leads to long lasting brain cholinergic alteration, probably related to oxidative stress immediately after the exposure, which is independent of classical inflammatory markers.


Assuntos
Etanol/administração & dosagem , Comportamento Exploratório/efeitos dos fármacos , Peixe-Zebra/fisiologia , Acetilcolinesterase/metabolismo , Animais , Comportamento Animal , Encéfalo/efeitos dos fármacos , Encéfalo/enzimologia , Colina O-Acetiltransferase/metabolismo , Etanol/farmacologia
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