Navegando por Palavras-chave "Acetylcholine"

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    Alpha-7 nicotinic receptor agonist protects mice against pulmonary emphysema induced by elastase
    (Springer Nature, 2024-06-01) Banzato, Rosana; Pinheiro-Menegasso, Nathalia Montouro [UNIFESP]; Santana, Fernanda Paula Roncon [UNIFESP]; Olivo, Clarice Rosa; Taguchi, Laura [UNIFESP]; Santos, Stheffany de Oliveira [UNIFESP]; Fukuzaki, Silvia; Teodoro, Walcy Paganelli Rosolia; Lopes, Fernanda Degobbi Tenorio Quirino dos Santos; Tibério, Iolanda de Fátima Lopes Calvo; Toledo-Arruda, Alessandra Choqueta de; Prado, Marco Antônio Máximo; Prado, Vania Ferreira; Prado , Carla Máximo [UNIFESP]; http://lattes.cnpq.br/9600880359624334; http://lattes.cnpq.br/8960401765088965; http://lattes.cnpq.br/0335008572194595; http://lattes.cnpq.br/0090429486050126; http://lattes.cnpq.br/4409788652533408; http://lattes.cnpq.br/1848955229237487; http://lattes.cnpq.br/0720259963845051; http://lattes.cnpq.br/2069814538238357; http://lattes.cnpq.br/7240963502716211; http://lattes.cnpq.br/8148205870336524; http://lattes.cnpq.br/2961494666434143; http://lattes.cnpq.br/8706664565242249; http://lattes.cnpq.br/3222014752923501; http://lattes.cnpq.br/1740478426977844; Universidade Federal de São Paulo (UNIFESP)
    Pulmonary emphysema is a primary component of chronic obstructive pulmonary disease (COPD), a life-threatening disorder characterized by lung inflammation and restricted airflow, primarily resulting from the destruction of small airways and alveolar walls. Cumulative evidence suggests that nicotinic receptors, especially the α7 subtype (α7nAChR), is required for anti-inflammatory cholinergic responses. We postulated that the stimulation of α7nAChR could offer therapeutic benefits in the context of pulmonary emphysema. To investigate this, we assessed the potential protective effects of PNU-282987, a selective α7nAChR agonist, using an experimental emphysema model. Male mice (C57BL/6) were submitted to a nasal instillation of porcine pancreatic elastase (PPE) (50 µl, 0.667 IU) to induce emphysema. Treatment with PNU-282987 (2.0 mg/kg, ip) was performed pre and post-emphysema induction by measuring anti-inflammatory effects (inflammatory cells, cytokines) as well as anti-remodeling and anti-oxidant effects. Elastase-induced emphysema led to an increase in the number of α7nAChR-positive cells in the lungs. Notably, both groups treated with PNU-282987 (prior to and following emphysema induction) exhibited a significant decrease in the number of α7nAChR-positive cells. Furthermore, both groups treated with PNU-282987 demonstrated decreased levels of macrophages, IL-6, IL-1β, collagen, and elastic fiber deposition. Additionally, both groups exhibited reduced STAT3 phosphorylation and lower levels of SOCS3. Of particular note, in the post-treated group, PNU-282987 successfully attenuated alveolar enlargement, decreased IL-17 and TNF-α levels, and reduced the recruitment of polymorphonuclear cells to the lung parenchyma. Significantly, it is worth noting that MLA, an antagonist of α7nAChR, counteracted the protective effects of PNU-282987 in relation to certain crucial inflammatory parameters. In summary, these findings unequivocally demonstrate the protective abilities of α7nAChR against elastase-induced emphysema, strongly supporting α7nAChR as a pivotal therapeutic target for ameliorating pulmonary emphysema.
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    Alterações plásticas da epileptogênese com ênfase na reorganização colinérgica
    (Universidade Federal de São Paulo (UNIFESP), 2006-01-01) Pereira, Heloisa Aparecida Alves [UNIFESP]; Mello, Luiz Eugenio Araujo de Moraes [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    Purpose: We investigated whether the administration of scopolamine, has the ability to interfere in the epileptogenic process and whether this effect could be explained by plastic changes in the cholinergic system. Methods: Two hours after pilocarpine-induced status epilepticus (SE, 320-350 mg/kg, i.p.), male Wistar rats received scopolamine (Pilo+Scopolamine group) 1-2 mg/kg i.p. or saline (Pilo group), every 6 hours for 3 days. After that, osmotic mimipumps were implanted for continuos delivery of scopolamine or saline for an additional 14 days. Animals were videomonitored for 12h/week during the following 3-months period for the occurrence of spontaneous recurrent seizures (SRS) and, thereafter, were perfused, processed and stained for acetylcholnesterase (AChE), neo-Timm and Nissl. Results: Administration of scopolamine decreased the number of SRS and increased latency for seizure onset. There was a decrease in the density of cholinergic positive fibers for AChE in all analised strutures of the Pilo+Scopolamine group as compared with Control and Pilo groups. Treatment with scopolamine however did not interfere with mossy fiber sprouting (MFS). Regression analysis did not indicate an association between SRS frequency and MFS or density of cholinergic fibers. Conclusions: The administration of scopolamine shortly after the inicial precipitant event and for a small period of time, lead to anatomical and functional consequences. Scopolamine interfered with epileptogenesis. However, the structural changes encountered with AChE histochemistry did not explain the epileptogenic and antiepileptogenic processes.
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    Análise do efeito do extrato padronizado de Ginkgo biloba na memória em camundongos com redução do transportador vesicular de acetilcolina (VAChT)
    (Universidade Federal de São Paulo, 2019) Veiga, Irina Emanuela Tavares da [UNIFESP]; Cerutti, Suzete Maria [UNIFESP]; Zamberlam, Cláudia Raquel [UNIFESP]; http://lattes.cnpq.br/4400354066404536; http://lattes.cnpq.br/9076343601956182; http://lattes.cnpq.br/0214678336393441
    O transportador vesicular de acetilcolina (VAChT) é necessário para as funções do sistema colinérgico no sistema nervoso central e periférico, pois participa da etapa crucial para o armazenamento da acetilcolina (ACh). A redução da sinalização colinérgica em áreas prosencefálicas, em especial no hipocampo e córtex pré-frontal (CPF), por modificação na atividade do VAChT, resulta em déficit de memória e de atenção, também descrito em pacientes com doença de Alzheimer (DA). Dados do nosso grupo evidenciaram que o tratamento crônico com o extrato padronizado de Ginkgo biloba (EGb) promoveu a neuroproteção de células do CPF, além de melhorar a memória de curto prazo. Esses dados em conjunto com dados da literatura que mostram que o EGb apresenta potencial de retardar a perda da função cognitiva relacionada com a idade, bem como melhorar as funções cerebrais de pacientes com a DA, fundamentam a nossa proposição. Esse estudo teve como objetivo avaliar o efeito do tratamento crônico com EGb em diferentes doses (250, 500 e 1000 mg.kg-1 ), em camundongos fêmeas, com 3-6 meses de idade, pesando 20 a 50 gramas,da linhagem C57BL/6, selvagem (WT) ou com redução de 65% ou 45% no transportador vesicular de ACh (VAChT Knockdown homozigoto ou heterozigoto, KDHOMO ou KDHETERO, respectivamente) (n=8/grupo). Os animais foram tratados por 30 dias com o EGb. No 24º dia do tratamento foram avaliados na tarefa de esquiva discriminativa no labirinto em cruz elevado modificado (PM-DAT), que permite avaliar concomitantemente memória, ansiedade e atividade locomotora espontânea do animal. Para análise comparativa das porcentagens de entrada e tempo foi utilizado a ANOVA one way ou two-way e teste-t, as diferenças foram consideradas significativas quando P<0,05. A análise dos dados revelou o efeito ansiolítico do EGb 500 mg.kg-1 relatado por estudos anteriores do grupo, revelam efeito modulatório do EGb, de forma dose-dependente, na memória de esquiva discriminativa, em animais saudáveis e com déficits colinérgicos, tais efeitos parecem dependentes do nível de comprometimento do sistema colinérgico. Ainda, demonstram que o nível de estradiol pode modular diferencialmente a memória os comportamentos relacionados com a ansiedade.
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    Avaliação comportamental e neuroquímica de camundongos com diminuição da expressão do transportador vesicular de acetilcolina (VAChT) tratados cronicamente com Extrato Padronizado de Ginkgo biloba (EGb): papel da formação hipocampal
    (Universidade Federal de São Paulo (UNIFESP), 2020-04-26) Muratori, Beatriz Gangale [UNIFESP]; Cerutti, Suzete Maria [UNIFESP]; Universidade Federal de São Paulo
    Memory has been described as a process that is related to an individual's ability to acquire, store and evoke information. Memory loss, or amnesia, is often associated with normal aging of the nervous system and appears more markedly in patients with neurodegenerative diseases. Alzheimer's disease (AD) is one of the most recurrent diseases today, and aging is one of the risk factors. Its occurrence is more common in women than in men. Other factors such as the formation of β-amyloid plaque, neurofibrillary tangles of the TAU protein and changes in the function of the cholinergic system have been related to the disease, the latter being the target of this study. The action of the cholinergic system in the modulation of memory or attention includes the joint action of the enzyme apparatus involved in the synthesis and degradation of acetylcholine (ACh), the activity of proteins related to cell transport, release and signaling. The cholinergic hypothesis has been considered as an important factor related to AD, since it was found a decrease in the expression of the neurotransmitter ACh in patients with the disease. In this sense, animal models that show reduced expression (knock-down, KD) of the vesicular acetylcholine transporter (VAChT) have also been used as a model for the study of AD and can help in understanding the mechanisms involved in the disease. Due to the damage caused by AD and its prevalence, as well as the limitation of current treatments, the search for new therapies that are more effective and efficient has directed the studies of different research groups. Previous data from the group showed that the use of Standardized Extract of Ginkgo biloba (EGb) improved the memory of conditioned fear and the memory of object recognition of healthy mice in the acute dose, in addition to having positive effects on anxiety and depression. Thus, this study aimed to evaluate the effect on EGb in the memory of mice that have deficit in cholinergic neurotransmission that characterizes them as a model of AD. This study aims to evaluate the effect of EGb on memory in mice with a 65% or 45% reduction in VAChT (KDHOM or KDHET, respectively). Additionally, we intend to understand the cellular and molecular mechanisms related to the disease through the analysis of the differential expression of proteins known to be involved in memory formation and related to the inflammatory processes described in AD. Female KDHOM and KDHET mice were used for VAChT and 3-month-old WT (WT, Wild Type) controls who were treated with EGb for 30 days and subjected to Recognition (T1, test 1) and Objects (T2, test 2). The animals were euthanized 24h after the end of T2, for removal of the dorsal hippocampal formation and subsequent analysis of molecular markers. The analysis of the data obtained suggests a cognitive enhancer effect of EGb in KDHET animals at doses 500 mg / Kg and 1000 mg / Kg and in KDHOM animals at dose 250 mg / Kg in object recognition memory, suggesting that the extract may exercise effect on the cholinergic system.
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    Avaliação da expressão dos componentes colinérgicos, citocinas e estresse oxidativo no pulmão e no sistema nervoso central em camundongos com lesão pulmonar aguda induzida por LPS intratraqueal
    (Universidade Federal de São Paulo, 2023-05-19) Castro, Stephanie Nonato de [UNIFESP]; Prado, Carla Máximo [UNIFESP]; Ribeiro, Alessandra Mussi [UNIFESP]; Pinheiro, Nathalia Montouro; http://lattes.cnpq.br/7373640456805525; http://lattes.cnpq.br/8960401765088965; http://lattes.cnpq.br/1740478426977844; http://lattes.cnpq.br/3531484981122245; Universidade Federal de São Paulo (UNIFESP)
    A síndrome do desconforto respiratório agudo é caracterizada por uma lesão pulmonar aguda, na qual há o recrutamento de células do sistema imune, liberação de citocinas inflamatórias e de espécies reativas de oxigênio. Este processo inflamatório pode afetar o sistema nervoso central com repercussões cognitivas. Nossa hipótese é que a lesão pulmonar aguda de origem pulmonar possa induzir alterações funcionais no sistema nervoso central. Objetivo: Avaliar se a lesão pulmonar induzida por lipopolissacarídeo via intratraqueal induz alterações cognitivas e dos componentes colinérgicos, citocinas e estresse oxidativo no cérebro em modelo de camundongo. Material e Métodos: Camundongos machos BALB/C receberam instilação intratraqueal de salina (Controle) ou lipopolissacarídeo (LPS, 5mg/Kg) e foram avaliados após 24 ou 48 horas. Foi realizado teste de tarefa de reconhecimento de objeto novo, que avalia memória de curto prazo, e, após a eutanásia, pulmão e estruturas cerebrais foram coletadas para análise de estresse oxidativo e de citocinas e componentes do sistema colinérgico por ELISA e/ou RT-PCR. Foi considerado p<0,05 como significativo. Resultados: O lipopolissacarídeo induziu perda de massa corpórea, edema pulmonar com presença de neutrófilos, macrófagos e linfócitos no lavado broncoalveolar e neutrófilos no tecido, além do aumento da área alveolar com distensão e colapso. Associado a estas alterações, houve aumento nos níveis de IL-1β, de IL-6, CXCL1/KC, TNF-α no lavado broncoalveolar e da expressão gênica de IL-6, NF-kB e do receptor mAChR M3 no pulmão. No teste de comportamento, os animais que receberam lipopolissacarídeo permaneceram um mesmo percentual de tempo explorando o objeto novo e o familiar, diferentemente do observado no grupo controle. Não houve aumento de citocinas e do estresse oxidativo no cérebro, exceto a atividade da SOD que foi reduzida e da catalase aumentada no hipocampo. Houve redução da expressão gênica do subtipos α4 no hipocampo e córtex pré- frontal, α7 no hipocampo e de acetilcolinesterase no córtex pré frontal. Houve correlação entre o tempo de exploração do objetivo novo e as alterações pulmonares e de sistema nervoso central. Conclusão: A inflamação pulmonar, caracterizada por aumento de edema pulmonar, de áreas colapsadas e distendidas, de células inflamatórias e citocinas no pulmão induziu um prejuízo na memória de curto prazo e a redução de receptores nicotinicos no sistema nervoso central. Estes dados sugerem que a inflamação periférica é um estímulo para deterioração das funções cognitivas, associado à redução de componentes colinérgicos no cérebro.
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    Biperiden (an M1 antagonist) reduces memory consolidation of cocaine-conditioned place preference
    (Elsevier B.V., 2012-04-04) Zacarias, Marina S. [UNIFESP]; Ramos, Anna C. [UNIFESP]; Alves, Danielle R. [UNIFESP]; Galduroz, Jose C. F. [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    It is well-known that cocaine dependence is a public health issue, and several studies stress the need to look for new and more effective treatments. Although the mesolimbic dopamine (DA) system, which originates in the ventral tegmental area (VTA) and projects to several forebrain structures, is known to be critically involved in the neurobiology of cocaine dependence, acetylcholine (ACh) has also been shown to play an important role in cocaine dependence via its action on this reward system. ACh is also important in the formation of hippocampal memory associated with appetitive behavior. Thus, the aim of this study was to evaluate the effect of biperiden, an ACh antagonist with high affinity for muscarinic M1 type receptors, on the acquisition of cocaine-conditioned place preference (CPP) in mice. the cocaine and biperiden were dissolved in sterile saline and were administered intraperitoneally at a dose of 10 mg/kg. the conditioning regime was 8 days long, and the cholinergic antagonist was given immediately at the end of each conditioning session. the test for CPP occurred 24 h after the last session. the results showed that animals treated with biperiden spent significantly less time in the cocaine-paired compartment than did the ones treated with saline. This finding represents a reduction in the consolidation of cocaine-induced CPP. One hypothesis that could explain this outcome focuses on the action of cholinergic antagonists on the consolidation of contextual memories. the amnesic effect of M1 antagonists on aversive tasks and on morphine CPP has been demonstrated when administered before the training or the conditioning session. the present study highlights the possibility of impairment in the acquisition of an appetitive memory, even when the cholinergic drug is administered after the conditioning session. This protocol also rejects the possibility of performance disturbance and suggests a possible pharmacological tool in the treatment of cocaine dependence. (c) 2012 Published by Elsevier Ireland Ltd.
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    Biperiden (M-1 antagonist) impairs the expression of cocaine conditioned place preference but potentiates the expression of cocaine-induced behavioral sensitization
    (Elsevier B.V., 2012-05-16) Ramos, Anna C. [UNIFESP]; Andersen, Monica L. [UNIFESP]; Oliveira, Maria G. M. [UNIFESP]; Soeiro, Aline C. [UNIFESP]; Galduroz, Jose C. F. [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    Cocaine addiction is a public health issue in many countries, stressing the need for more effective treatments. As all drugs of abuse, cocaine acts on the brain reward system, increasing dopamine (DA) levels. Other neurotransmitters such as acetylcholine (ACh) are involved in the mechanisms underlying the development and the maintenance of cocaine addiction. ACh plays an important role in learning and memory processes and also regulates DA in some specific regions of the central nervous system. the present study investigated the effects of biperiden, a muscarinic cholinergic (mACh) antagonist in two animal models: conditioned place preference (CPP) and behavioral sensitization. Male C57BL/6J mice were used in both studies. the CPP protocol was unbiased and carried out in three phases: habituation, conditioning and testing. for conditioning, cocaine was injected at a dose of 10 mg/kg in eight 15 min-sessions. the treatment with biperiden (doses of 0.1, 1 and 10 mg/kg) was made 30 min prior to the testing session. for behavioral sensitization development, cocaine was administered at the dose of 10 mg/kg for 10 days. After sensitization, two challenges were performed: saline and cocaine (5 mg/kg). Biperiden (10 mg/kg) was administered 30 min before the cocaine challenge. At the dose of 10 mg/kg, biperiden blocked the cocaine-CPP expression, suggesting an effect on conditioned memory retrieval. However, the same dose potentiated the expression of behavioral sensitization, suggesting an increase in DA release, probably in the NAc. Biperiden, as other mACh antagonists, may be a promising drug for the pharmacologic treatment of cocaine addiction. (C) 2012 Elsevier B.V. All rights reserved.
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    Disfunção endometrial tardia apos revascularização percutanea: resposta coronária a acetilcolina antes e depois da aplicação de nitroglicerina transdermica
    (Universidade Federal de São Paulo (UNIFESP), 1996) Lima, Valter Correia de [UNIFESP]; Carvalho, Antonio Carlos [UNIFESP]
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    Efeito do exercício físico aeróbio em modelo experimental de enfisema pulmonar: participação do sistema colinérgico antiinflamatório
    (Universidade Federal de São Paulo (UNIFESP), 2018) Souza, Natália Tiemi Simokomaki [UNIFESP]; Prado, Carla Máximo [UNIFESP]; http://lattes.cnpq.br/1740478426977844; http://lattes.cnpq.br/0946248445669212; Universidade Federal de São Paulo (UNIFESP)
    Introdução: O enfisema pulmonar é uma doença que tem alta incidência, morbidade e mortalidade e está associada à exposição a fumaça de cigarro. É caracterizada por inflamação pulmonar e perda de função. A acetilcolina (ACh), cuja liberação está relacionada aos níveis de transportador vesicular de ACh (VAChT), é o principal mediador do sistema colinérgico anti-inflamatório, e controla a inflamação pulmonar. O exercício físico aeróbio tem um importante efeito anti-inflamatório e melhora a qualidade de vida dos pacientes com enfisema pulmonar. Objetivos: 1. Elucidar se a redução de VAChT e da liberação de ACh interfere no desenvolvimento do enfisema; 2. Elucidar se a redução de VAChT interfere nos efeitos benéficos do exercício físico aeróbio neste modelo. Métodos: Camundongos transgênicos com redução parcial de VAChT (KD) e selvagens (WT) machos (6-8 semanas) foram submetidos ao protocolo de exposição à fumaça de cigarro (2x/dia5x/semana/12semanas). Os grupos expostos à fumaça de cigarro foram subdivididos e submetidos ou não ao protocolo de treinamento físico aeróbio na esteira 5x/semana/60minutos/sessão/12 semanas. Após este período, foi avaliada a função pulmonar e após a eutanásia foi coletado o fluido do lavado broncoalveolar (BALF) para contagem total e diferencial de células. Os pulmões foram submetidos às técnicas habituais histológicas com parafina e coloração Hematoxilina e Eosina, para avaliação do diâmetro alveolar (Lm). Foram analisadas as citocinas IL-17 e IFN- γ no BALF. Resultados: O tempo do teste de grade e a massa corpórea foram menores nos animais KD (p<0,01) em relação aos WT. A exposição à fumaça de cigarro reduziu a massa corpórea nos WT (p<0,05) e nos KD (p<0,001). Animais WT e KD expostos ao cigarro apresentaram aumento do diâmetro alveolar (p<0,001) e do número de células totais (p<0,05) e de macrófagos (p<0,05) em relação aos respectivos controles. Os animais KD expostos ao cigarro apresentaram aumento de neutrófilos (p<0,01) e linfócitos (p<0,01) e redução de elastância tecidual (p<0,01). Os animais KD apresentaram redução dos níveis de IFNγ no BALF (p<0,05) em relação aos grupos WT. Os animais KD expostos à fumaça de cigarro e submetidos ao treinamento físico apresentaram menor velocidade, tempo e distância percorrida em relação aos WT (p<0,001), entretanto ambos os grupos (KD e WT) aumentaram estes parâmetros quando comparado os valores finais com iniciais (p<0,01). Nos animais expostos ao fumo, o treinamento físico reduziu o diâmetro alveolar nos animais WT (p<0,05), não tendo efeito nos animais KD. Em relação às células inflamatórias, o treinamento físico aumentou o número de células totais e de macrófagos somente nos animais WT (p<0,01), não tendo efeito nos KD. Ainda o treinamento físico em animais KD aumentou o número de neutrófilos (p<0,05). O treinamento físico aumentou a elastância tecidual tanto nos animais WT quanto KD expostos ao cigarro (p<0,05). Conclusão: Em conjunto, nossos dados sugerem que o sistema colinérgico anti-inflamatório está envolvido no controle da resposta inflamatória pulmonar em modelo de doença pulmonar obstrutiva crônica induzida por exposição à fumaça de cigarro, e os efeitos benéficos do treinamento físico, pelo menos em parte, dependem do sistema colinérgico íntegro
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    Estudo do teste farmacológico com acetilcolina e cloreto de bário como monitor funcional do jejuno e de ileo, com e sem mucosa e após preservação em ratos: estudo "in vitro"
    (Universidade Federal de São Paulo (UNIFESP), 1994) Taha, Murched Omar [UNIFESP]; Koh, Ivan Hong Jun [UNIFESP]
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    Extrato Padronizado de Ginkgo biloba reverte prejuízo cognitivo em camundongas velhas com disfunção colinérgica no prosencéfalo basal: modulação de β-amiloide e tau fosforilada
    (Universidade Federal de São Paulo, 2024-07-26) Muratori, Beatriz Gangale [UNIFESP]; Cerutti, Suzete Maria [UNIFESP]; Ureshino, Rodrigo Portes [UNIFESP]; http://lattes.cnpq.br/7174742745591377; http://lattes.cnpq.br/9076343601956182; http://lattes.cnpq.br/1116361980756316
    Normative aging involves various adaptive changes within the hippocampal formation, leading to memory impairments, particularly affecting the dentate gyrus. In contrast, Late-onset Alzheimer’s Disease (LOAD) is the most common neurodegenerative disease, primarily affecting women. LOAD involves the extracellular deposition of misfolded amyloid beta (Aβ) peptides and intracellular accumulation of hyperphosphorylated tau. Dysfunction in the hippocampal formation (HF) and prefrontal cortex due to reduced acetylcholine (ACh) signaling from basal forebrain cholinergic neurons contributes to cognitive impairments such as attention deficits, memory formation issues, and difficulties in decision-making. Since current medications for AD often prove limited effects, exploring multi-target substances as therapeutic alternatives is crucial. Our research has demonstrated that the standardized extract of Ginkgo biloba (EGb) acts as a cognitive enhancer by regulating key proteins involved in memory formation. Additionally, EGb exhibits anti-apoptotic, anti-inflammatory, and neuroprotective effects. This study aims to evaluate the effects of chronic EGb treatment on object recognition memory (ORM) and object location memory (OLM) in aged female mice of wild-type (WT) and VAChT knockdown (KD) genotypes: KDHET (45% reduction in VAChT) and KDHOM (65% reduction in VAChT). Additionally, it explores the relationship between aversive memory and anxiety using the plus-maze discriminative avoidance task (PM-DAT). Western blotting (WB) analyzed Aβ and phosphorylated tau (p-tau) expression in the HF, while immunohistochemistry (IR+ cells) examined these markers in dorsal hippocampal subfields (CA1, CA3) and the dentate gyrus (DG). Moreover, in vitro studies were conducted to investigate EGb's interaction with Aβ using Langmuir films, which mimic the plasma membrane and characterize protein-extract interactions. Our findings indicate that aging impairs memory formation in discriminative avoidance memory and OLM. Additionally, aged mice with severe cholinergic dysfunction exhibit impairment in ORM, OLM, and PM-DAT. Treatment with EGb at 250 mg/kg effectively reverses these impairments, correlating with modulation of p-tau levels in the HF and an increase in Aβ-IR+ cell counts in the CA1 region and dentate gyrus (DG). The increase in Aβ may result from EGb’s interaction with Aβ and the POPC monolayer in vitro, which significantly reduces the density of aggregates. In summary, this study advances our understanding of EGb’s effects in aged female mice, both with and without cholinergic dysfunction. It highlights EGb’s impact on Aβ and p-tau proteins, emphasizing its potential implications for cognitive function and neuroprotection.
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    Greater cytosolic and mitochondrial calcium transients in adrenal medullary slices of hypertensive, compared with normotensive rats
    (Elsevier B.V., 2010-06-25) Miranda-Ferreira, Regiane [UNIFESP]; Pascual, Ricardo de; Smaili, Soraya Soubhi [UNIFESP]; Caricati-Neto, Afonso [UNIFESP]; Gandia, Luis; Garcia, Antonio G.; Jurkiewicz, Aron [UNIFESP]; Univ Autonoma Madrid; Universidade Federal de São Paulo (UNIFESP)
    Pronounced differences in the kinetics of single-vesicle catecholamine release from adrenal chromaffin cells stimulated with acetylcholine or high potassium (K(+)) have been recently found between normotensive Wistar rats (NWRs) and spontaneously hypertensive rats (SHRs). Such differences could be explained on the basis of distinct mechanisms of calcium (Ca(2+)) handling by chromaffin cells of NWRs and SHRs. We have explored here this hypothesis in adrenal medullary slices loaded with calcium fluorescent probes to measure the changes in Ca(2+) concentration in the cytosol ([Ca(2+)](c)), endoplasmic reticulum ([Ca(2+)](er)), and mitochondria ([Ca(2+)](m)). We found the following differences on calcium handling in SHRs, as compared with NWR: (i) higher basal [Ca(2+)](c) and basal [Ca(2+)](m); (ii) greater [Ca(2+)](c) elevations elicited by acetylcholine and K(+), with faster activation but slower inactivation; (iii) greater [Ca(2+)](c) elevations elicited by CRT (a mixture of caffeine, ryanodine, and thapsigargin) and by the mitochondrial protonophore FCCP (carbonylcyanide p-(trifluoromethoxy) phenylhydrazone). the higher basal [Ca(2+)](c) and [Ca(2+)](m) suggest an enhanced mitochondrial Ca(2+) uptake, and the greater [Ca(2+)](c) elevations produced by FCCP indicates a higher mitochondrial Ca(2+) release into the cytosol. This alteration of intracellular Ca(2+) movements could explain the greater quantal catecholamine release responses seen in SHRs, as compared with NWRs in previous studies. Furthermore, enhanced mitochondrial Ca(2+) cycling may be the basis for the dysfunction of mitochondrial bioenergetics, reported to be present in hypertensive states. (C) 2010 Elsevier B.V. All rights reserved.
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    M1 muscarinic receptors are necessary for retrieval of remote context fear memory
    (Pergamon-Elsevier Science Ltd, 2017) Patricio, Rafael Rodisanski [UNIFESP]; Kramer Soares, Juliana Carlota [UNIFESP]; Menezes Oliveira, Maria Gabriela [UNIFESP]
    Several studies have investigated the transition of consolidation of recent memory to remote memory in aversively motivated tasks, such as contextual fear conditioning (CFC) and inhibitory avoidance (IA). However, the mechanisms that serve the retrieval of remote memories, has not yet been fully understood. Some evidences suggest that the central cholinergic system appears be involved in the modulation of these processes. Therefore, the present study aimed to investigate the effects of a pre-test administration of dicyclomine, a high-affinity M1 muscarinic receptor antagonist, on the retrieval of remote memories in fear conditioning and IA tasks. Male Wistar rats were trained, and after 1 or 28 days, the rats received dicyclomine (16 or 32 mg/lcg, intraperitoneally, i.p.) and were tested in CFC, tone fear conditioning (TFC) and IA tasks. At both time intervals, 32 mg/kg dicydomine induced impairment of CFC. In TFC task only the performance of the rats 28 days after training was impaired. The IA task was not affected in any of the studied intervals. These findings suggest a differential contribution of muscarinic receptors on recent and remote memories retrieval revealing a more generalized role in remote memory. (C) 2016 Elsevier Inc. All rights reserved.
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    Muscarinic Acetylcholine Receptor Subtypes in the Male Reproductive Tract
    (Humana Press Inc, 2010-01-01) Avellar, Maria Christina Werneck [UNIFESP]; Siu, Erica Rosanna [UNIFESP]; Yasuhara, Fabiana [UNIFESP]; Marostica, Elisabeth; Porto, Catarina Segreti [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade Federal Fluminense (UFF)
    In mammals, at least five different muscarinic acetylcholine receptor subtypes (mAChRs; M(1)-M(5)) are known to be widely expressed and distributed in different tissues from different species. They mediate distinct physiological functions according to their location and receptor subtype. Multiple events are associated with the regulation of intracellular signaling by mAChRs, and a coordinated balance of the molecular mechanisms governing receptor signaling, desensitization, resensitization, and mitogenic signaling is known to occur in various cell types. Most of the actions of acetylcholine (ACh) in the male reproductive tract are induced by its effects on mAChRs, but the role of specific mAChR subtypes on male reproductive function and fertility are still not well understood. the rat efferent ductules and epididymis are androgen-dependent tissues of the male reproductive tract, with important roles in the process to form a viable and fertile sperm. in the present study, aspects of the expression, localization, and potential function of mAChR subtypes in rat efferent ductules and epididymis are reviewed. Furthermore, evidences for the implication of mAChRs in the regulation of protein synthesis and secretion in these tissues are presented. Taken together, the studies contribute to our understanding about physiological aspects of mAChR and mechanisms by which the cholinergic system affects male reproduction.
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    O papel da deficiência colinérgica na mucosa bucal de camundongos expostos à fumaça do cigarro
    (Universidade Federal de São Paulo (UNIFESP), 2020-10-06) Sousa, Thamires Cristina Furlanetti de [UNIFESP]; Ribeiro, Daniel Araki [UNIFESP]; Moura, Carolina Foot Gomes de [UNIFESP]; http://lattes.cnpq.br/7337258146927440; http://lattes.cnpq.br/9969803499258672; http://lattes.cnpq.br/6055311539909897; Universidade Federal de São Paulo (UNIFESP)
    O tabagismo constitui um grande problema de Saúde Pública por participar da patogênese de diversas doenças crônico-degenerativas, incluindo o câncer. A acetilcolina é um neurotransmissor capaz de inibir a resposta inflamatória por meio da via anti-inflamatória colinérgica, cuja deficiência na vesícula transportadora de acetilcolina (VAChT) resulta em um estado pró-inflamatório sistêmico. Neste estudo, foi avaliada a expressão de marcadores inflamatórios e de proliferação celular na mucosa bucal de camundongos com deficiência de expressão do VAChT e expostos à fumaça do cigarro. Para tanto, 8 camundongos machos selvagens/wild type (WT) e 8 camundongos machos deficientes (knockdown, KD) para VAChT foram distribuídos em 4 grupos experimentais (n=4): Grupo WT - Camundongos selvagens / wild-type (controle) não expostos à fumaça de cigarro; Grupo KD - Camundongos com deficiência de expressão do VAChT não expostos à fumaça de cigarro; Grupo WT+Fumo - Camundongos selvagens / wild-type expostos à fumaça de cigarro por 12 semanas e Grupo KD+Fumo - camundongos com deficiência de expressão de VAChT expostos à fumaça de cigarro por 12 semanas. Os resultados da análise do marcador inflamatório TNF-alfa apontaram diferença estatística em todos os grupos experimentais quando comparados ao grupo controle (WT). Na análise imunoistoquímica para o marcador ki-67 foi observado que os animais do grupo controle e expostos ao fumo (grupo WT + FUMO) apresentaram um aumento na proliferação celular quando comparados aos animais dos grupos WT e KD. A análise histopatológica da língua dos animais mostrou que o grupo KD+ FUMO apresentou redução no número de focos de displasia epitelial comparado aos animais dos grupos KD e WT + FUMO. Em suma, tais resultados sugerem que a exposição à fumaça do cigarro é capaz de induzir aumento da atividade inflamatória e proliferação celular, sendo dependente da presença da acetilcolina.
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    Participação Do Ampc Extracelular Na Regulação Da Transmissão Neuromuscular Esquelética
    (Universidade Federal de São Paulo (UNIFESP), 2017-09-28) Duarte, Thiago [UNIFESP]; Godinho, Rosely Oliveira [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    Introduction: In skeletal muscle, the intracellular cyclic AMP regulates processes that include the contraction, metabolism, and expression of synaptic proteins (Duarte et al., 2001; Bergantin et al. 2011). Studies of our group have shown that after the activation of GsPCR or adenylyl cyclase, part of the newly formed intracellular cAMP is transported to the cellular interstitium (Godinho and Costa-Jr 2003; Chiavegatti et al., 2008). The cAMP is able to act as an extracellular signaling molecule through its metabolite adenosine, formed by the sequential action of ecto-phosphodiesterases and ecto-5'-nucleotidases (Chiavegatti et al., 2008). More recently, we have demonstrated that β2 adrenoceptor activation has a biphasic action characterized by the initial potentiation of muscle contraction resulting from the increase of intracellular cAMP, followed by a negative inotropic effect, related to cAMP efflux and activation of A1 receptors by the adenosine metabolite (Duarte et al, 2012). It is known that adenosine formed from ATP released by the motor neuron is able to modulate neuromuscular transmission through its adenosine metabolite and activation of neuronal adenosine receptors (Ribeiro J.A, et al., 1996), but in skeletal muscle, It was not identified whether the efflux and metabolism of cAMP, regulates the neuromuscular transmission Objective: Evaluate the participation of extracellular cAMP and its metabolite adenosine in neuromuscular transmission. Methods: Male diaphragm muscles were used for 3 to 4 months, and muscle contraction was induced by electrical stimulation of the phrenic nerve (n = 3-4). The train-of-four TOF electrical stimulation protocol (2 Hz, 2 ms duration) was used and the ratio between the contraction amplitude of the fourth (T4) and the first stimulus (T1) was determined to evaluate the effect of the neuromuscular blockers d-tubocurarine and hexamethonium in the presence or absence of cAMP, clenbuterol and / or formoterol, with or without preincubation of adenosine receptor antagonists (CGS15943 and ZM241385) or inhibitors of organic anion (probenecid) ecto-5'-nucleotidase (AMPCP). The effect of formoterol on intra- and extracellular cAMP was quantified by time resolving-FRET assay.Results: 300 nM d-tubocurarine and 1.5 mM hexamethonium caused 25% neuromuscular block, this effect was inhibited by the 30 min preincubation with 100 μM cAMP and by the agonists of β2adenoceptors 100 nM clenbuterol and 100 nM formoterol which also promoted a 15% increase in contraction force, these effects were associated with increased of intracellular and extracellular cAMP levels. The adenosine receptor antagonists 100 nM CGS15943 (non-selective) and 100 nM ZM241385 (A2A selective) and the inhibitors of organic anion (300 μM probenecid) and ecto-5'-nucleotidase (100 μM AMPCP) inhibited the effect cAMP and clenbuterol on d-tubocurarine and hexamethonium-induced tetanic fade. Conclusions: The results presented in this work show that the extracellular cAMP adenosine pathway initiated by activation of post-synaptic β2 adrenoceptors modulates the contraction of skeletal muscle induced by phrenic nerve stimulation. These modulations depend on efflux of cAMP and activation of presynaptic adenosine receptors and probably involve increment in ACh release. However, this pathway can act as a paracrine signaling that creates feedback loop and regulation between muscle fibers and motor neurons.
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    Sleep pattern and learning in knockdown mice with reduced cholinergic neurotransmission
    (Associação Brasileira de Divulgação Científica, 2013-01-01) Queiroz, Claudio Marcos [UNIFESP]; Tiba, Paula Ayko; Moreira, Karin Monteiro [UNIFESP]; Guidine, Patrícia Alves Maia; Rezende, Gustavo H S; Moraes, Márcio Flávio Dutra; Prado, Marco Antônio Máximo; Prado, Vânia Ferreira; Tufik, Sergio [UNIFESP]; Mello, Luiz Eugenio Araujo de Moraes [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade Federal do Rio Grande do Norte Instituto do Cerebro; Universidade Federal do ABC Computacao e Cognicao Centro de Matematica; Universidade Federal de Minas Gerais Departamento de Fisiologia e Biofisica Nucleo de Neurociencias; University of Western Ontario Department of Physiology and Pharmacology and Department of Anatomy and Cell Biology Robarts Research Institute
    Impaired cholinergic neurotransmission can affect memory formation and influence sleep-wake cycles (SWC). In the present study, we describe the SWC in mice with a deficient vesicular acetylcholine transporter (VAChT) system, previously characterized as presenting reduced acetylcholine release and cognitive and behavioral dysfunctions. Continuous, chronic ECoG and EMG recordings were used to evaluate the SWC pattern during light and dark phases in VAChT knockdown heterozygous (VAChT-KDHET, n=7) and wild-type (WT, n=7) mice. SWC were evaluated for sleep efficiency, total amount and mean duration of slow-wave, intermediate and paradoxical sleep, as well as the number of awakenings from sleep. After recording SWC, contextual fear-conditioning tests were used as an acetylcholine-dependent learning paradigm. The results showed that sleep efficiency in VAChT-KDHET animals was similar to that of WT mice, but that the SWC was more fragmented. Fragmentation was characterized by an increase in the number of awakenings, mainly during intermediate sleep. VAChT-KDHET animals performed poorly in the contextual fear-conditioning paradigm (mean freezing time: 34.4±3.1 and 44.5±3.3 s for WT and VAChT-KDHET animals, respectively), which was followed by a 45% reduction in the number of paradoxical sleep episodes after the training session. Taken together, the results show that reduced cholinergic transmission led to sleep fragmentation and learning impairment. We discuss the results on the basis of cholinergic plasticity and its relevance to sleep homeostasis. We suggest that VAChT-KDHET mice could be a useful model to test cholinergic drugs used to treat sleep dysfunction in neurodegenerative disorders.