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Protein-Energy Malnutrition Modifies the Production of Interleukin-10 in Response to Lipopolysaccharide (LPS) in a Murine Model

FOCK, Ricardo Ambrosio; VINOLO, Marco Aurelio Ramirez; CRISMA, Amanda Rabello; NAKAJIMA, Karina; ROGERO, Marcelo Macedo; BORELLI, Primavera
Fonte: CENTER ACADEMIC PUBL JAPAN Publicador: CENTER ACADEMIC PUBL JAPAN
Tipo: Artigo de Revista Científica
Português
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56.6%
Malnutrition modifies resistance to infection by impairing a number of physiological processes including hematopoesis and the immune response. In this study, we examined the production of Interleukin-4 (IL-4) and IL-10 in response to lipopolysaccharide (LPS) and also evaluated the cellularity of the blood, bone marrow, and spleen in a mouse model of protein-energy malnutrition. Two-month-old male Swiss mice were subjected to protein-energy malnutrition (PEM) with a low-protein diet (4%) as compared to the control diet (20%). When the experimental group lost approximately 20% of their original body weight, the animals from both groups received 1.25 mu g of LPS intravenously. The Cells ill the blood, bone marrow, and spleen were counted, and circulating levels of IL-4 and IL-10 were evaluated in animals stimulated with LPS. Cells from the spleen, bone marrow, and peritoneal cavity of non-inoculated animals were collected for Culture to evaluate the production of IL-4 and IL-10 after stimulating these cells with 1.25 mu g of LPS in vitro. Malnourished animals presented leucopenia and a severe reduction in bone marrow, spleen, and peritoneal cavity cellularity before and after Stimulus with LPS. The circulating levels of IL-10 were increased in malnourished animals inoculated with LPS when compared to control animals...

Low-Intensity Swimming Training Partially Inhibits Lipopolysaccharide-Induced Acute Lung Injury

RAMOS, Daniel Souza; OLIVO, Clarice Rosa; LOPES, Fernanda Degobbi Tenorio Quirino Santos; TOLEDO, Alessandra Choqueta; MARTINS, Milton Arruda; OSORIO, Rodrigo Alexis Lazo; DOLHNIKOFF, Marisa; RIBEIRO, Wellington; VIEIRA, Rodolfo De Paula
Fonte: LIPPINCOTT WILLIAMS & WILKINS Publicador: LIPPINCOTT WILLIAMS & WILKINS
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
46.63%
RAMOS, D. S. C. R. OLIVO. F. D. QUIRINO SANTOS LOPES, A. C. TOLEDO, M. A. MARTINS, R. A. LAZO OSORIO. M. DOLHNIKOFF, W. RIBEIRO, and R. R VIEIRA. Low-Intensity Swimming Training Partially Inhibits Lipopolysaccharide-Induced Acute Lung Injury. Med. Sci. Sports Exerc.. Vol. 42, No. 1, pp. 113-119, 2010. Background: Aerobic exercise-decreases pulmonary inflammation and remodeling in experimental models of allergic asthma. However, the effects of aerobic exercise oil pulmonary inflammation of nonallergic Origin, such as in experimental models of acute long injury induced by lipopolysaccharide (LPS), have not been evaluated. Objective: The present study evaluated file effects of aerobic exercise in a model of LPS-induced acute lung injury. Methods: BALB/c mice were divided into four groups: Control, Aerobic Exercise, LPS, and Aerobic Exercise + LPS. Swimming tests were conducted at baseline and at 3 and 6 wk. Low-Intensity swimming training was performed for 6 wk, four times per week, 60 min per session. Intranasal LPS (1 mg.kg(-1) (60 mu g per mouse)) was instilled 24 It after the last swimming physical test in the LPS and Aerobic Exercise + LPS mice, and the animals were studied 24 It after LPS instillation. Exhaled nitric oxide, respiratory mechanics...

Caracterização do eixo imune-pineal: glândula pineal como alvo para lipopolissacarídeo (LPS); Characterization of immune-pineal axis: pineal gland as a sensor for lipopolysaccharide (LPS)

Machado, Sanseray da Silveira Cruz
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 24/08/2010 Português
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56.63%
O fator de transcrição nuclear kappa B (NFKB), central na resposta inflamatória, é constitutivamente expresso em glândulas pineais de rato. A inibição da translocação nuclear deste fator em pineais de rato por corticosterona potencia, enquanto que a inibição pela citocina fator de necrose tumoral (TNF) inibe a síntese de melatonina por inibição da transcrição da Aa-nat. Esta redução da produção noturna de melatonina está implicada em favorecer a montagem da resposta inflamatória. Embora dados da literatura sugerirem redução da produção de melatonina durante processos infecciosos, não há evidências diretas da habilidade da glândula pineal em reconhecer o lipopolissacarídeo (LPS), a endotoxina da membrana de bactérias gram-negativas. Esta dissertação investigou se a glândula pineal de ratos expressa receptores para o reconhecimento do LPS e estabeleceu possíveis mecanismos de ação desta endotoxina na glândula pineal de ratos. Nossos resultados demonstram que a glândula pineal expressa de maneira constitutiva os receptores CD14 e o TLR4. LPS induz a translocação nuclear dos dímeros p50/p50 e p50/RelA e a síntese de TNF em glândulas cultivadas. A máxima produção de TNF no meio de cultura é coincidente com a máxima expressão do receptor TNFR1 em pinealócitos. Além disso...

Efeito da inoculação de lipopolissacarídeo em ratos recém-nascidos sobre o comportamento exploratório na adolescência; Effect of lipopolysaccharide inoculation in newborn rats on exploratory behavior in adolescence

Rodriguez, Javier Leonardo Rico
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 28/01/2011 Português
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46.63%
A administração do componente bacteriano lipopolissacarídeo (LPS) durante o início de vida é um modelo animal comumente utilizado de infecção precoce. Os efeitos desse tratamento sobre o comportamento exploratório têm sido geralmente observados em ratos adultos. Contudo, sabe-se pouco sobre esses efeitos em etapas importantes do desenvolvimento como a adolescência. O presente trabalho analisou o efeito da inoculação repetida de LPS em ratos recém-nascidos, sobre o comportamento exploratório. No primeiro experimento, filhotes machos de ratos Wistar foram distribuídos em três grupos (N = 12) e receberam injeções intraperitoneais de solução veículo (PBS) ou de LPS (E. coli; 0,05 mg/kg), ou foram mantidos sem tratamento, nos dias 3 e 5 de vida. Na adolescência, entre os dias 40 e 46 de vida, os animais foram expostos aos seguintes testes comportamentais: labirinto em cruz elevado, campo aberto, reconhecimento de objeto novo, tábua de buracos, gradiente de aversão elevado e nado forçado. Os resultados mostraram que ratos adolescentes expostos a esse paradigma de inoculação exibiram um perfil de comportamento impulsivo caracterizado pelo aumento de locomoção, exploração de áreas abertas e baixa neofobia, quando comparados com os animais dos grupos controle. Esses animais exibiram também um estilo ativo de lidar com o estresse na primeira sessão do nado forçado. Semelhante ao procedimento utilizado no primeiro experimento...

Avaliação in vivo e in vitro do efeito do extrato de própolis em osso alveolar, com e sem contaminação de lipopolissacarídeo bacteriano; In vivo and in vitro effects of propolis extract on alveolar bone, with and without bacterial lipopolysaccharide contamination

Pereira, Yamba Carla Lara
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 20/12/2010 Português
Relevância na Pesquisa
56.71%
A própolis é uma substância resinosa, cujas atividades antibacteriana, antiinflamatória, antiviral, fungicida, imuno estimulante, cicatrizante e de anestésico local tem sido valorizadas no uso clínico. O lipopolissacarídeo (LPS) é reconhecidamente uma endotoxina e pode induzir processos inflamatórios. Os objetivos deste trabalho foram: a) analisar in vitro as seguintes propriedades do extrato de própolis verde: 1) perfil físico químico 2) Concentração Inibitória Mínima (CIM) frente à endotoxina da bactéria gram negativa Escherichia coli; e 3) sua atividade imunorregulatória sobre leucócitos de baço de ratos; b) analisar ″in vivo″ a ação do Extrato Etanólico de Própolis (EEP) 10% e 90% e do Extrato de Própolis Puro (EPP), em alvéolos dentais contaminados ou não com lipopolissacarídeo (LPS) bacteriano. Para o estudo in vivo 35 ratos foram submetidos às exodontias dos primeiros molares superiores direito e esquerdo, os quais, imediatamente tiveram o alvéolo dental direito contaminado com 0,1µL de lipopolissacarídeo (LPS) (100µg/kg) e o esquerdo sem tal contaminação. Os grupos com (n=7) para cada tratamento, após 2 semanas: GI- Controle Negativo (CN) - sem tratamento; GII- Tratados com Extrato de Própolis puro (EPP) GIII- Tratados com pasta de própolis a 90% (P90); GIV- Tratados com pasta de própolis a 10% (P10); e...

Ciclooxigenase-2 modula in vivo a expressão de marcadores da osteoclastogênese e genes envolvidos no metabolismo ósseo em resposta ao lipopolissacarídeo bacteriano; Ciclooxygenase-2 modulates in vivo the expression of osteoclastiogenesis makers and genes involved in bone metabolism in response to bacterial lipopolysaccharide

Santos, Fernanda Regina Ribeiro
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 06/06/2012 Português
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46.61%
Durante a resposta inflamatória, diversos mediadores são liberados localmente com o objetivo de estimular a resposta imune celular e humoral. Por meio da ação das enzimas ciclooxigenases e lipoxigenases ocorrerão modificações estruturais na cadeia do ácido araquidônico levando a síntese de prostaglandinas ou leucotrienos e lipoxinas, respectivamente. Tais mediadores são responsáveis pela regulação da expressão dos genes RANK, RANKL e OPG, moduladores da osteoclastogênese. Dessa maneira, o objetivo deste estudo foi avaliar a expressão do RNA mensageiro (RNAm) para as enzimas envolvidas no metabolismo do ácido araquidônico, ciclooxigenase-2 (COX-2) e 5- lipoxigenase (5-LO), e para os mediadores da osteoclastogênese (RANK, RANKL e OPG) no tecido ósseo, após inoculação de lipopolissacarídeo bacteriano (LPS) nos canais radiculares de molares de camundongos. Posteriormente foi investigado o efeito do bloqueio farmacológico da via COX-2 induzida pelo LPS, na expressão de mediadores da osteoclastogênese e de genes envolvidos no metabolismo ósseo. Foram utilizados 144 camundongos C57BL/6, com 6 semanas de idade, pesando de 18 a 20 gramas, nos quais os canais radiculares dos primeiros molares foram inoculados com uma solução contendo lipopolissacarídeo bacteriano de E. coli (0...

The Role of Lipopolysaccharide on the Electrochemical Behavior of Titanium

Barao, Valentim Adelino Ricardo; Mathew, M. T.; Assuncao, W. G.; Yuan, J. C.; Wimmer, M. A.; Sukotjo, C.
Fonte: Sage Publications Inc Publicador: Sage Publications Inc
Tipo: Artigo de Revista Científica Formato: 613-618
Português
Relevância na Pesquisa
46.66%
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Lipopolysaccharide (LPS) may induce peri-implantitis and implant failure. However, the role of LPS in titanium (Ti) electrochemical behavior remains unknown. We hypothesized that LPS in saliva with different pHs affects Ti corrosion properties. Thirty-six Ti discs (15 mm x 3 mm) were divided into 12 groups according to saliva pH (3, 6.5, and 9) and Escherichia coli LPS concentration (0, 0.15, 15, and 150 mu g/mL). Electrochemical tests, such as open circuit potential, potentiodynamic, and electrochemical impedance spectroscopy, were conducted in a controlled environment. Data were evaluated by Pearson correlation and regression analysis (alpha = 0.05). LPS and pH affected Ti corrosive behavior. In general, lower pH and higher LPS concentration accelerated Ti corrosion. In the control group, the increase of pH significantly reduced the corrosion rate and increased the capacitance of the double layer. In LPS groups, the decrease of pH significantly increased the corrosion rate of Ti. LPS negatively influenced Ti corrosion behavior. Abbreviations: C(dl), capacitance of double layer; E(corr), corrosion potential; EIS, electrochemical impedance spectroscopy; I(corr)...

Mecanismo da incubação de enterotoxinas estafilococicas e do lipopolissacaride na agregação e na adesão de plaquetas humanas; Incubation effects of staphylococcal enterotoxins and lipopolysaccharide in human platelets aggregation and adhesion

Rafael Prada Morganti
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 24/07/2008 Português
Relevância na Pesquisa
46.66%
A sepsis é a segunda causa de morte em pacientes internados em unidades de tratamento intensivo não coronariano. Pacientes com sepsis apresentam anormalidades plaquetárias como trombocitopenia, prolongamento do tempo de coagulação, coagulação intravascular disseminada, trombose microvascular maciça e sangramentos. Entretanto, os mecanismos envolvidos nestas alterações plaquetárias ainda são mal compreendidos. O objetivo deste trabalho foi investigar as ações do lipopolissacarídeo (LPS) de E. coli, e de enterotoxinas de Staphylococcus aureus (SEA e SEB), na adesão e na agregação de plaquetas humanas, bem como os mecanismos envolvidos nesses fenômenos. As plaquetas foram expostas ao LPS, SEA ou SEB em diferentes concentrações e tempos de incubação para avaliação in vitro da adesão ou agregação. Além disso, realizou-se experimentos para verificar o papel do óxido nítrico (NO) e de espécies reativas de oxigênio nas ações induzidas pelo LPS, SEA e SEB, assim como a sinalização intracelular (mobilização de Ca+2) e ativação do receptor do fibrinogênio glicoproteína IIb/IIIa (GPIIb/IIIa). A incubação de plaquetas com LPS, SEA e SEB por períodos 5 a 120 min inibiu a adesão espontânea das plaquetas ao fibrinogênio...

Propofol exerts anti-inflammatory effects in rats with lipopolysaccharide-induced acute lung injury by inhibition of CD14 and TLR4 expression

Ma,Ling; Wu,Xiu-Ying; Zhang,Li-Hong; Chen,Wei-Min; Uchiyama,Akinori; Mashimo,Takashi; Fujino,Yuji
Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2013 Português
Relevância na Pesquisa
46.63%
We investigated the effect of propofol (Prop) administration (10 mg kg-1 h-1, intravenously) on lipopolysaccharide (LPS)-induced acute lung injury and its effect on cluster of differentiation (CD) 14 and Toll-like receptor (TLR) 4 expression in lung tissue of anesthetized, ventilated rats. Twenty-four male Wistar rats were randomly divided into three groups of 8 rats each: control, LPS, and LPS+Prop. Lung injury was assayed via blood gas analysis and lung histology, and tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) levels were determined in bronchoalveolar lavage fluid using ELISA. Real-time polymerase chain reaction was used to detect CD14 and TLR4 mRNA levels, and CD14 and TLR4 protein expression was determined by Western blot. The pathological scores were 1.2 ± 0.9, 3.3 ± 1.1, and 1.9 ± 1.0 for the control, LPS, and LPS+Prop groups, respectively, with statistically significant differences between control and LPS groups (P < 0.05) and between LPS and LPS+Prop groups (P < 0.05). The administration of LPS resulted in a significant increase in TNF-α and IL-1β levels, 7- and 3.5-fold...

Seladin-1 is a novel lipopolysaccharide (LPS)-responsive gene and inhibits the tumour necrosis factor-α production and osteoclast formation in response to LPS

Khuda, Imtiaz I-E; Koide, Naoki; Noman, Abu S M; Dagvadorj, Jargalsaikhan; Tumurkhuu, Gantsetseg; Naiki, Yoshikazu; Komatsu, Takayuki; Yoshida, Tomoaki; Yokochi, Takashi
Fonte: Blackwell Science Inc Publicador: Blackwell Science Inc
Tipo: Artigo de Revista Científica
Publicado em /09/2010 Português
Relevância na Pesquisa
46.61%
Selective Alzheimer disease indicator-1 (seladin-1) is a broadly expressed oxidoreductase and is related to Alzheimer disease, cholesterol metabolism and carcinogenesis. The effect of lipopolysaccharide (LPS) on the expression of seladin-1 was examined using RAW 264.7 macrophage-like cells and murine peritoneal macrophages. Lipopolysaccharide induced the expression of seladin-1 protein and messenger RNA in those macrophages. The seladin-1 expression was also augmented by a series of Toll-like receptor ligands. The LPS augmented the expression of seladin-1 via reactive oxygen species generation and p38 activation. Seladin-1 inhibited LPS-induced activation of p38 but not nuclear factor-κB and inhibited the production of tumour necrosis factor-α in response to LPS. Moreover, seladin-1 inhibited LPS-induced osteoclast formation and enhanced LPS-induced alkaline phosphatase activity. Therefore, it was suggested that seladin-1 might be an LPS-responsible gene product and regulate the LPS-induced inflammatory response negatively.

Assembly and Regulation of the Lipopolysaccharide Transporter

Freinkman, Elizaveta
Fonte: Harvard University Publicador: Harvard University
Tipo: Thesis or Dissertation
Português
Relevância na Pesquisa
46.61%
The hallmark of Gram-negative bacteria is the presence of an outer membrane (OM) surrounding the cytoplasmic membrane (here called the inner membrane [IM]) and the cell wall. The OM is a unique asymmetric bilayer with an inner leaflet consisting of phospholipid and an outer leaflet consisting of lipopolysaccharide (LPS). LPS is a large anionic molecule that typically contains six fatty acyl chains and up to several hundred sugar residues. This chemical structure explains why the OM is relatively impermeable to large hydrophobic molecules, such as detergents, bile salts, and high molecular weight antibiotics, which readily cross a normal phospholipid bilayer. LPS and the OM are essential to the viability of most Gram-negative organisms, including major human pathogens. LPS molecules are biosynthesized at the IM and subsequently exported out of the IM, across the intermembrane space (the periplasm) and through the OM to their final position at the cell surface. In Escherichia coli, the essential LPS transport proteins, LptA-G, are required for this process. This Lpt pathway includes an IM adenosine triphosphate binding cassette (ABC) transporter, LptBFG, which is associated with an additional IM protein, LptC; a periplasmic protein...

Implementa????o e otimiza????o do teste Lal para an??lise de LPS de cianobac??rias em cultura e da regi??o estuarina da Lagoa dos Patos e praia adjacente

Gutierrez, Fabiane Bretanha
Fonte: Universidade Federal do Rio Grande Publicador: Universidade Federal do Rio Grande
Tipo: Dissertação de Mestrado
Português
Relevância na Pesquisa
56.51%
Disserta????o(mestrado) - Universidade Federal do Rio Grande, Programa de P??s-Gradua????o em Oceanografia F??sica, Qu??mica e Geol??gica, Instituto de Oceanografia, 2007.; Flora????es de cianobact??rias t??m sido freq??entemente encontradas nas ??guas do estu??rio da Lagoa dos Patos (RS). Um das principais cianobact??rias de ocorr??ncia local ?? o g??nero Microcystis. As c??lulas de Microcystis t??m toler??ncia a baixas salinidades, por??m com o aumento abrupto da salinidade, as c??lulas podem sofrer lise. Muitas vezes, em fun????o da hidrodin??mica local, essas flora????es de cianobact??rias podem atingir a regi??o da Praia do Cassino, possibilitando o contato com banhistas. Devido ?? natureza Gram-negativa da composi????o da parede celular das cianobact??rias, esse contato com as c??lulas pode resultar em na ocorr??ncia de casos de irrita????o epicut??nea e rea????es al??rgicas. O agente causador ?? o lip??deo A (endotoxina), encontrado no lipopolissacar??deo (LPS) da membrana externa das cianobact??rias. Com o objetivo de detectar concentra????es ambientais de LPS das flora????es de cianobact??rias foi utilizado o m??todo cromog??nico cin??tico de ponto final do teste do Lisado do Ameb??cito de Limulus polyphemus (teste LAL). O teste LAL foi realizado em amostras de ??gua de superf??cie coletadas nas regi??es de S??o Louren??o do Sul...

Prenatal exposure to lipopolysaccharide results in neurodevelopmental damage that is ameliorated by zinc in mice

Chua, J.; Cowley, C.; Manavis, J.; Rofe, A.; Coyle, P.
Fonte: Academic Press Inc Publicador: Academic Press Inc
Tipo: Artigo de Revista Científica
Publicado em //2012 Português
Relevância na Pesquisa
46.61%
There is converging evidence that during pregnancy a maternal immune response to infection can cause neurodevelopmental damage. Lipopolysaccharide (LPS)-mediated induction of metallothionein (MT) and subsequent hypozincaemia has been linked to fetal brain damage. Our group has demonstrated that Zn, when co-administered with LPS in early pregnancy in mice (gestation day (GD) 8), prevents fetal malformations and neurodevelopmental deficits in offspring. Others demonstrating fetal brain lesions have administered LPS much later in gestation (after GD 16), when the influence of LPS-mediated MT-induction on maternal plasma Zn levels, and the effect of Zn co-administration with LPS, are unknown. The aims of this study are firstly to examine whether LPS causes MT induction and maternal hypozincaemia in mid-to-late pregnancy, and secondly to determine if histochemical markers of inflammatory damage in fetal brain are affected by LPS and whether this damage can be alleviated with Zn treatment. Pregnant mice were injected with LPS (5 mg/kgbodywt.) or saline vehicle on GD 16 and then humanely killed at 8, 16 and 24 h for Zn and MT measurements, or concomitantly injected subcutaneously with Zn (2 mg/kgbodywt.) or saline and then killed on GD 18 and immunohistochemistry performed on fetal brain. Maternal hepatic MT was markedly induced after LPS-challenge and this was associated with a 38% reduction in maternal plasma Zn concentrations. Coincidentally...

Neuronale Aktivierung im Nucleus Tractus Solitarius nach intrajejunaler und systemischer Lipopolysaccharidgabe im Dünndarm der Ratte; Neuronal activation in the nucleus tractus solitarius (NTS) following intrajejunal and systemic lipopolysaccharide (LPS) in the rat

Gakis, Georgios
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
Português
Relevância na Pesquisa
46.68%
Einleitung: Systemisches LPS sensibilisiert mesenterische afferente Nervenfasern im Intestinum der Ratte, wobei die Cycloxigenase aktivierende und NO hemmende Wirkung besitzt. (Gastroenterology 2003; 124: M1298). Intestinale Entzündungsvorgänge können über eine Mastzellaktivierung Fos-positive Neurone des Nucleus Tractus Solitarius (NTS) im Hirnstamm aktivieren (Neuroscience Letters 2000; 289: 45-48). Wir stellten die Hypothese auf, dass afferente Signale nach intrajejunaler und systemischer Lipopolysaccharidgabe (LPS) in den NTS weitergeleitet werden und diese neuronale Aktivierung im Hirnstamm pharmakologisch beeinflussbar sei. Methoden: Die Experimente wurden an männlichen Wistar-Ratten (300-400 g) durchgeführt. Hierbei wurde vier Tage nach operativer Anlage eines Jejunalkatheters E.coli-LPS entweder lokal über den Katheter (10 mg ml-1, Volumen: 2 ml, Dauer: 3h) oder systemisch als Bolus durch intraperitoneale Injektion (1 mg kg-1) appliziert. Zur Untersuchung der pharmakologischen Beeinflussbarkeit der neuronalen Aktivierung im Hirnstamm wurde in Subgruppen vor systemischer LPS-Gabe der Cyclooxigenasehemmer Naproxen (10 mg kg-1) oder der iNOS-Inhibitor Aminoguanidin (15 mg kg-1) intraperitoneal appliziert. Drei Stunden nach Abschluss der LPS-Gabe erfolgte die Gabe einer Pentobarbitalüberdosierung und die Blutprobengewinnung zur Bestimmung der Serum-LPS Konzentration mittels LAL-Chromogenic Endpoint Assay. Nachfolgend Perfusion des Tieres mit NaCl- und Formalinlösung sowie Entnahme des Gehirns zur immunohistochemischen Untersuchung. Die neuronale Aktivierung im NTS wurde mittels c-Fos-Immunohistochemie in den Höhen 13.3 mm...

Lipopolysaccharide-induced memory impairment in rats is preventable using 7-nitroindazole

Anaeigoudari,Akbar; Shafei,Mohammad Naser; Soukhtanloo,Mohammad; Sadeghnia,Hamid Reza; Reisi,Parham; Beheshti,Farimah; Mohebbati,Reza; Mousavi,Seyed Mojtaba; Hosseini,Mahmoud
Fonte: Academia Brasileira de Neurologia - ABNEURO Publicador: Academia Brasileira de Neurologia - ABNEURO
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2015 Português
Relevância na Pesquisa
46.63%
Inflammation and oxidative stress have important roles in memory impairment. The effect of 7-nitroindazole (7NI) on lipopolysaccharide (LPS)-induced memory impairment was investigated. Rats were used, divided into four groups that were treated as follows: (1) control (saline); (2) LPS; (3) 7NI-LPS; and (4) 7NI before passive avoidance (PA). In the LPS group, the latency for entering the dark compartment was shorter than in the controls (p < 0.01 and p < 0.001); while in the 7NI-LPS group, it was longer than in the LPS group (p < 0.01 and p < 0.001). Malondialdehyde (MDA) and nitric oxide (NO) metabolite concentrations in the brain tissues of the LPS group were higher than in the controls (p < 0.001 and p < 0.05); while in the 7NI-LPS group, they were lower than in the LPS group (p < 0.001 and p < 0.05, respectively). The thiol content in the brain of the LPS group was lower than in the controls (p < 0.001); while in the 7NI-LPS group, it was higher than in the LPS group (p < 0.001). It is suggested that brain tissue oxidative damage and NO elevation have a role in the deleterious effects of LPS on memory retention that are preventable using 7NI.

Lipopolysaccharide treatment reduces rat platelet aggregation independent of intracellular reactive-oxygen species generation

Elisa Lopes-Pires, M.; Casarin, Andre L.; Pereira-Cunha, Fernanda G.; Lorand-Metze, Irene; Antunes, Edson; Marcondes, Sisi
Fonte: Informa Healthcare; London Publicador: Informa Healthcare; London
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
46.61%
High production of reactive-oxygen species (ROS) by blood cells is involved in damage of the vascular endothelium and multiple organ dysfunction in sepsis. However, little is known about the intraplatelet ROS production in sepsis and its consequences on platelet reactivity. In this study, we evaluated whether the treatment of rats with lipopolysaccharide (LPS) affects platelet aggregation through intraplatelet ROS generation. Rats were injected with LPS (1 mg/kg, i.p.), and at 2 to 72 h thereafter, adenosine diphosphate (ADP) (3-10 mu M) induced platelet aggregation was evaluated. Production of ROS in platelets was measured by flow cytometry using 2',7'-dichlorofluorescein diacetate (DCFH-DA). Treatment of rats with LPS time-dependently inhibited ADP-induced platelet aggregation within 72 h. The inhibitory effect of LPS on platelet aggregation was further increased when the platelets were incubated with polyethylene glycol-superoxide dismutase (PEG-SOD; 30 U/mL), polyethylene glycol-catalase (PEG-CAT; 1000 U/mL) or the NADPH oxidase inhibitor diphenyleneiodonium (DPI; 10 mu M). The ROS production in non-stimulated platelets did not differ between control and LPS-treated rats. However, in ADP-activated platelets, generation of ROS was increased by 3.0- and 7.0-fold...

Lipopolysaccharide-induced expression of cell surface receptors and cell activation of neutrophils and monocytes in whole human blood

Gomes,N.E.; Brunialti,M.K.C.; Mendes,M.E.; Freudenberg,M.; Galanos,C.; Salomão,R.
Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2010 Português
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Lipopolysaccharide (LPS) activates neutrophils and monocytes, inducing a wide array of biological activities. LPS rough (R) and smooth (S) forms signal through Toll-like receptor 4 (TLR4), but differ in their requirement for CD14. Since the R-form LPS can interact with TLR4 independent of CD14 and the differential expression of CD14 on neutrophils and monocytes, we used the S-form LPS from Salmonella abortus equi and the R-form LPS from Salmonella minnesota mutants to evaluate LPS-induced activation of human neutrophils and monocytes in whole blood from healthy volunteers. Expression of cell surface receptors and reactive oxygen species (ROS) and nitric oxide (NO) generation were measured by flow cytometry in whole blood monocytes and neutrophils. The oxidative burst was quantified by measuring the oxidation of 2',7'-dichlorofluorescein diacetate and the NO production was quantified by measuring the oxidation of 4-amino-5-methylamino-2',7'-difluorofluorescein diacetate. A small increase of TLR4 expression by monocytes was observed after 6 h of LPS stimulation. Monocyte CD14 modulation by LPS was biphasic, with an initial 30% increase followed by a 40% decrease in expression after 6 h of incubation. Expression of CD11b was rapidly up-regulated...

Prenatal lipopolysaccharide increases maternal behavior, decreases maternal odor preference, and induces lipopolysaccharide hyporesponsiveness

Penteado,Sandra; Gomes,Cristina de Oliveira Massoco-Salles; Kirsten,Thiago; Reis-Silva,Thiago; Melo,Rafael César de; Acenjo,Michelli; Queiroz-Hazarbassanov,Nicolle; Bernardi,Maria Martha
Fonte: Pontificia Universidade Católica do Rio de Janeiro; Universidade de Brasília; Universidade de São Paulo Publicador: Pontificia Universidade Católica do Rio de Janeiro; Universidade de Brasília; Universidade de São Paulo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2013 Português
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The present study investigated whether late maternal inflammation disrupts the mother/pup interaction, resulting in long-lasting effects on pup behavior and alterations in biological pathways, thereby programming prepubertal behavior and the pups' inflammatory responses after bacterial endotoxin treatment. Female rats received 100 μg/kg lipopolysaccharide (LPS) or .9% saline solution on gestation day 18. Reproductive performance was observed at birth. On lactation days (LD) 5 and LD 6, respectively, maternal behavior and maternal aggressive behavior were assessed. In pups, maternal odor preference on LD 7, open field behavior on LD 21, and serum tumor necrosis factor α (TNF-α) levels after LPS challenge on LD 21 were investigated. The results showed that prenatal LPS exposure improved maternal care and reduced maternal aggressive behavior but did not alter maternal reproductive performance. Male offspring exhibited increased body weights at birth and reduced maternal odor preference. Lipopolysaccharide challenge increased the duration of immobility in the open field and induced a slight increase in serum TNF-α levels. Prenatal exposure to LPS during late pregnancy improved maternal care, reduced maternal olfactory preference...

Participación de la anandamida en la reabsorción embrionaria murina inducida por lipopolisacárido; Participation of anandamide in lipopolysaccharide-induced embryonic resorption in mice

Vercelli, Claudia Alejandra
Fonte: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires Publicador: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires
Tipo: info:eu-repo/semantics/doctoralThesis; tesis doctoral; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em //2010 Português
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La anandamida (AEA), el endocannabinoide más abundante en el tracto reproductivo, es un importante mediador de los procesos de implantación y desarrollo embrionario pero niveles elevados de esta molécula en el útero son perjudiciales. A su vez, el óxido nítrico (NO) y las prostaglandinas (PGs) están involucrados en la reabsorción embrionaria (RE) inducida por lipopolisacárido (LPS). En varios trabajos se ha descripto que el LPS modula la producción de AEA y que ésta interacciona con el NO y las PGs. Por ello, estudiamos si este endocannabinoide estaba implicado en la RE inducida por LPS en el útero y la decidua de ratón durante la preñez temprana, evaluando su participación en un modelo in vitro. Observamos que tanto en el útero como en la decidua, el LPS tiene importantes efectos sobre el sistema endocannabinoide (SEC) modulando la síntesis y la degradación de AEA y la expresión de los receptores de estos compuestos (receptores de cannabinoides, CB). Demostramos también que la AEA induce su propio catabolismo en la decidua. Por otro lado, encontramos que la AEA media el efecto estimulatorio del LPS sobre la síntesis de NO y la expresión de la NO sintasa inducible (NOSi), a través de sus receptores específicos. También hallamos que la AEA participa en la modulación que ejerce el LPS sobre el camino biosintético de las PGs...

Lipopolysaccharide Reverses Adrenocorticotrophic Hormone-Induced Hypertension in the Rat

Zhang, Yi; Schyvens, Chris; McKenzie, Katja; Morris, Brian; Whitworth, Judith
Fonte: Japanese Society for Hypertension Publicador: Japanese Society for Hypertension
Tipo: Artigo de Revista Científica
Português
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Lipopolysaccharide (LPS) was used to stimulate nitric oxide (NO) release and investigate the effect of endogenous NO on adrenocorticotrophic hormone (ACTH)-induced hypertension in rats. After preliminary studies to determine the appropriate dose of LPS, 40 male Sprague-Dawley rats were treated with ACTH (200 μg/kg/day, s.c.) or saline (sham) for 8 days and then given a single dose of LPS (10 mg/kg, i.p.) or saline. ACTH treatment was continued for a further 5 days. Systolic blood pressure (SBP) was measured daily using the tail cuff method. Results were expressed as the mean±SEM. ACTH treatment significantly increased SBP (from 105±3 to 129±4 mmHg; p<0.05), whereas saline had no effect on SBP. The ACTH-induced increase in SBP was reversed by LPS injection (from 125±6 to 102±7 mmHg; p<0.05). SBP was also decreased in sham + LPS-treated rats compared with that of sham + saline-treated rats (p<0.05), but the SBP change in response to LPS was greater in ACTH-treated than in sham-treated rats (-23 vs. -8 mmHg; p<0.05). These data are compatible with the notion that reduced NO availability plays a role in ACTH-induced hypertension.