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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Efeitos do exercício físico e da suplementação com chá-verde sobre características bioquímicas e comportamentais associadas ao envelhecimento / Effects of physical exercise and green tea on behavioral and biochemical aspects of cognition in aging

Flôres, Maíra Frigo 08 November 2013 (has links)
Submitted by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2016-04-08T19:23:35Z No. of bitstreams: 1 Maíra Frigo Flores.pdf: 606784 bytes, checksum: 320f5eb7c4c92844adfadf846bcd39d7 (MD5) / Made available in DSpace on 2016-04-08T19:23:35Z (GMT). No. of bitstreams: 1 Maíra Frigo Flores.pdf: 606784 bytes, checksum: 320f5eb7c4c92844adfadf846bcd39d7 (MD5) Previous issue date: 2013-11-08 / O envelhecimento causa rejuízos cognitivos e de memória que têm sido relacionados com o estresse oxidativo (EO). Descobrir formas de atenuar o EO é importante para minimizar perdas cognitivas. O exercício físico e as catequinas constituintes do chá verde são potenciais antioxidantes que podem auxiliar na proteção das funções cognitivas e de memória. Ao passo que evidências sugerem papel neuroprotetor do exercício, efeitos do chá verde durante o envelhecimento como estratégia para combater o EO ainda são bastante incipientes. Essa pesquisa verificou os efeitos do exercício físico e da suplementação com o chá verde sobre aspectos bioquímicos e comportamentais associados ao envelhecimento. Ratos Wistar com 9 meses de idade foram divididos em grupos, sendo eles: controle, exercício, chá verde, exercício e chá verde, além de um grupo controle jovem. As intervenções foram feitas por três meses, constando de exercício aeróbico e ingestão de chá verde de maneira isolada, e realização de exercício aeróbico com concomitante ingesta de chá verde. Em conclusão, o chá verde não evitou déficits cognitivos no envelhecimento, mas diminuiu as espécies reativas aumentando as defesas antioxidantes. O exercício melhorou diversos parâmetros bioquímicos e comportamentais. A falta de efeito do chá verde na cognição pode estar relacionada com as características da intervenção, ao passo que a diminuição nas espécies reativas sugere um papel de proteção do chá verde mesmo em um período curto de suplementação. / Aging is associated with cognitive and mnemonic deficits frequently reported as related to the oxidative stress (OS). There is continuous interest to minimize effects of OS in order to avoid cognitive deficits. Physical exercise and catechines from green tea are potential antioxidants helping to protect cognitive and memory functions. While there are evidences supporting the neuroprotective role of physical exercise, the effects of green tea supplementation during aging as strategy to combat OS still are quiet incipient. In this study the effects of physical exercise and green tea supplementation on biochemical and behavioral characteristics associated with aging were addressed. Wistar rats 9 months aged were organized in groups as follow: young control group; aged control group; exercise aged group; green tea supplementation aged group; exercise and green tea supplementation aged group. Interventions lasted 3 months composed by aerobic exercise and green tea, combined or not. Green tea was not effective in avoid cognitive deficits associated with aging, but significantly decreases ROS activity with significant improve in antioxidants defenses. Physical exercise improved all parameter in both biochemical and behavioral testing. The lack of effects of green tea on cognition may rely on the duration of the intervention, while decrease in the ROS suggests its effect role even during a short supplementation period.
112

Papel protetor da infusão do chá verde sobre o dano induzido pela ciclofosfamida no sistema reprodutor de camundongos / Protective role of the green tea infusion on damage cyclophosphamide-induced on reproductive system of mice

Zanchi, Mariane Magalhães 26 July 2014 (has links)
Submitted by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2016-04-18T17:36:59Z No. of bitstreams: 1 MARIANE MAGALHÃES ZANCHI.pdf: 1185149 bytes, checksum: 5b02afd42e868819a353f05a3e1fb99a (MD5) / Made available in DSpace on 2016-04-18T17:36:59Z (GMT). No. of bitstreams: 1 MARIANE MAGALHÃES ZANCHI.pdf: 1185149 bytes, checksum: 5b02afd42e868819a353f05a3e1fb99a (MD5) Previous issue date: 2014-07-26 / A ciclofosfamida (CF) é um agente antineoplásico e imunossupressor, usada no tratamento de diversos tipos de tumores e em algumas doenças auto-imunes. A CF é considerada um pró-fármaco, portanto, precisa sofrer biotransformação hepática para formar seus metabólitos ativos, como a mostarda fosforamida e a acroleína. Seu metabólito terapêutico, a mostarda fosforamida, é responsável pelo efeito citotóxico na célula tumoral, enquanto a acroleína é conhecida por apresentar um efeito tóxico secundário, por aumentar a produção de espécies reativas ao oxigênio, causando estresse oxidativo. Esse, por sua vez, poderia estar diretamente relacionado com a redução da fertilidade causada por esta droga. Diante disso, compostos naturais com atividade antioxidante poderiam ser uma alternativa ao dano causado pela CF. O chá verde, obtido da planta Camellia sinensis, tem ação antioxidante e scavenger de radicais livres, devido ao alto conteúdo de polifenóis. O presente estudo avalia o papel protetor da infusão do chá verde sobre o dano oxidativo no sistema reprodutor de camundongos machos, e a sua relação com a fertilidade, após uma administração aguda de CF. Os camundongos foram pré-tratados por gavagem com veículo ou chá verde diariamente, por 14 dias, na dose de 250 mg/kg. A CF foi administrada via intraperitoneal no 14o dia, 1 hora após a administração do chá, na dose de 100 mg/kg. Os camundongos foram eutanasiados 24 horas após a administração da CF, e os testículos e epidídimos foram retirados para posteriores análises bioquímicas e avaliação espermática. O conteúdo de catequinas, principais constituintes do chá verde foi avaliada por HPLC. Epigalocatequina galato (EGCG) está presente em alta concentração na nossa infusão (1340,2 μg/mL), seguido por epicatequina (EC-500,95 μg/mL) e epicatequina galato (ECG-302,84 μg/mL). CF causou estresse oxidativo no sistema reprodutor dos animais, evidenciado neste trabalho por danificar tanto lipídios, como proteínas e DNA. A CF causou um aumento na peroxidação lipídica (níveis de MDA), dano de DNA (ensaio cometa) e atividade da enzima superóxido dismutase (SOD), enquanto diminuiu a atividade da glutationa peroxidase (GPx), glutationa-S-transferase (GST) e 17β–hidroxiesteróide desidrogenase (17β–HSD) em ambos os tecido testados. A atividade da enzima catalase (CAT) e a quantificação de proteína carbonil foram alteradas somente em testículo, mas não em epidídimo. Em relação à avaliação espermática, CF reduziu significativamente apenas a concentração de espermatozóides, comparado ao controle. O pré-tratamento com a infusão do chá verde reduziu significativamente a produção de MDA, carbonilação de proteína, dano de DNA e restaurou a atividade da GPx e GST. Em epidídimo, o chá verde também aumentou a concentração espermática e restaurou a atividade da enzima 17β–HSD. Pode-se concluir que a infusão do chá verde melhora o dano induzido pela CF, no sistema reprodutor de camundongos, e este efeito poderia ser atribuído ao alto conteúdo de catequinas presentes no chá e à sua atividade antioxidante. / Cyclophosphamide (CP) is an antineoplastic and immunosuppressive agent used to treat various types of tumors and in some autoimmune diseases. CP is considered a prodrug, therefore, must undergo hepatic biotransformation to form its active metabolites, such as phosphoramide mustard and acrolein. Its therapeutic metabolite, phosphoramide mustard, is responsible for the cytotoxic effect on tumor cells, while acrolein is known to provide a secondary toxic effect by increasing the reactive oxygen species production, causing oxidative stress. This might be directly related to the fertility reduction caused by this drug. Therefore, natural compounds with antioxidant activity could be an alternative to the damage caused by CP. Green tea, obtained from the plant Camellia sinensis, has antioxidant and free radical scavenging effect, due to the high content of polyphenols. The present study evaluates the protective role of the green tea infusion on oxidative damage on male mice reproductive system, and their relationship to fertility after an acute administration of CP. The mice were pre-treated by gavage with vehicle or green tea daily for 14 days at dose of 250 mg/kg. CP was administered intraperitoneally on day 14, 1 hour after administration of tea at dose of 100 mg/kg. Mice were euthanized 24 hours after the administration of the CP and testes and epididymis were removed for further biochemical analysis and sperm assessment. The content of catechins, the main constituents of green tea were evaluated by HPLC. Epigallocatechin gallate (EGCG) is present in high concentrations in our infusion (1340.2 μg/ml), followed by epicatechin (EC-500.95 μg/ml) and epicatechin gallate (ECG-302.84 μg/mL). CP caused oxidative stress in the reproductive system of animals, evidenced in this work by damaging not only lipids, but also proteins and DNA. CP increased lipid peroxidation (MDA), DNA damage (comet assay) and superoxide dismutase (SOD) activity, while decreased glutathione peroxidase (GPx), glutathione-S-transferase (GST) and 17β-hydroxysteroid dehydrogenase (17β-HSD) activity in both tissues tested. Catalase (CAT) activity and quantification of protein carbonyl were altered only in testes but not in the epididymis. Regarding sperm evaluation, CF significantly decreased only sperm concentration, compared to the control group. Pre-treatment with green tea infusion significantly reduced MDA production, protein carbonylation, DNA damage and restored GPx and GST activity. In epididymis, green tea also increased sperm concentration and restored 17 β-HSD activity. Green tea infusion improves the damage induced by CP in the reproductive system of mice, and this effect is attributed to the high content of catechins in tea and its antioxidant activity.
113

Wirkung von Teecatechin Epigallocatechingallat auf den Energiestoffwechsel der Maus / Effect of tea catechin epigallocatechin gallate on energy metabolism in mice

Friedrich, Maika January 2010 (has links)
Die gesundheitsfördernden Eigenschaften von grünem Tee sind weitgehend akzeptiert. Den Teecatechinen, insbesondere dem Epigallocatechin-3-gallat (EGCG), werden zahlreiche positive Effekte zugesprochen (z. B. antioxidativ, antikanzerogen, antiinflammatorisch, Blutdruck und Cholesterinspiegel senkend). Die Mechanismen, die zu einer Reduktion der in Tierversuchen beschriebenen Körper- und Fettmasse führen, sind nicht ausreichend geklärt. Ziel dieser Arbeit bestand darin, die kurz- und mittelfristigen Wirkungen einer TEAVIGO®-Applikation (mind. 94 % EGCG) am Mausmodell im Hinblick auf den Energie- und Fettstoffwechsel sowie die Expression daran beteiligter Gene in wichtigen Organen und Geweben zu untersuchen. In verschiedenen Tierversuchen wurde männlichen C57BL/6-Mäusen eine Hochfettdiät (HFD) mit und ohne Supplementation (oral, diätetisch) des entkoffeinierten Grüntee-Extraktes TEAVIGO® in unterschiedlichen Dosierungen gefüttert. Es wurden sowohl kurz- als auch mittelfristige Wirkungen des EGCG auf die Energiebilanz (u. a. indirekte Tierkalorimetrie) und Körperzusammensetzung (NMR) sowie die exogene Substratoxidation (Stabilisotopentechnik: Atemtests, Inkorporation natürlicher 13C-angereicherter Triglyceride aus Maiskeimöl in diverse Organe/Gewebe) und Gen-expression (quantitative real-time PCR) untersucht. Die Applikationsform und ihre Dauer riefen unterschiedliche Wirkungen hervor. Mäuse mit diätetischer Supplementation zeigten bereits nach kurzer Zeit eine verminderte Körperfettmasse, die bei weiterer Verabreichung auch zu einer Reduktion der Körpermasse führte. Beide Applikationsformen resultieren, unabhängig von der Dauer der Intervention, in einer erhöhten Energieausscheidung, während die Futter- und Energieaufnahme durch EGCG nicht beeinflusst wurden. Der Energieverlust war von einer erhöhten Fett- und Stickstoffausscheidung begleitet, deren Ursache die in der Literatur beschriebene Interaktion und Hemmung digestiver Enzyme sein könnte. Besonders unter postprandialen Bedingungen wiesen EGCG-Mäuse erniedrigte Triglycerid- und Glycogengehalte in der Leber auf, was auf eine eingeschränkte intestinale Absorption der Nährstoffe hindeutet. Transkriptanalysen ergaben im Darm eine verminderte Expression von Fettsäuretransportern, während die Expression von Glucosetransportern durch EGCG erhöht wurde. Weiterhin reduzierte EGCG, nach Umstellung von Standard- auf eine maiskeimölhaltige Hochfettdiät, die Inkorporation natürlicher 13C-angereicherter Triglyceride in diverse Organe und Gewebe – insbesondere Leber, viszerales und braunes Fettgewebe sowie Skelettmuskel. Die Analyse der 13C-Anreicherung im Atem der Mäuse und die Energieumsatzmessungen ergaben nach kurzer Applikation eine erhöhte Fettoxidation, die im weiteren Verlauf der Intervention auf eine erhöhte Kohlenhydratoxidation umgeschaltet wurde. Weiterhin war die orale Applikation von EGCG bei gleichzeitiger Fütterung einer Hochfettdiät von makroskopischen und mikroskopischen degenerativen Veränderungen der Leber begleitet. Diese Effekte wurden nach diätetischer Supplementation der Hochfettdiät mit EGCG nicht beobachtet. Zusammenfassend zeigen die Ergebnisse, dass die Körpergewichts- und Fettgewebs-abnahme durch diätetisches EGCG sich durch eine herabgesetzte Verdaulichkeit der Nahrung erklären lässt. Dies führte zu verschiedenen kurz- und mittelfristigen Veränderungen in der Fettverteilung und im Fettmetabolismus. / The health-promoting properties of green tea are widely accepted. Tea catechins, particularly epigallocatechin-3-gallate (EGCG), are attributed to many positive effects (anti-oxidative, anti-cancerogen, anti-inflammatory, blood pressure and cholesterol lowering). Mechanisms leading to a reduction of body mass and fat mass in animal experiments are not fully elucidated. The aim of this study was to examine multiple effects of TEAVIGO® application (at least 94% EGCG) in a mouse model in terms of energy and fat metabolism. Expressions of genes involved in these processes were also determined in different organs and tissues. In several animal studies, male C57BL/6 mice were fed a high fat diet supplemented with decaffeinated TEAVIGO® (oral, dietetic) at different dosages. Short- and medium-term effects of EGCG were investigated on energy balance (indirect animal calorimetry), body composition (NMR), exogenous substrate oxidation (stable isotopes: breath tests, incorporation of naturally 13C-enriched triglycerides from corn oil into various organs/tissues), and gene expression (quantitative real-time PCR). Type of application and its duration elicited different effects. Supplemented mice already showed a reduced body fat mass after short- and medium-term treatment. Further administration lead to a reduction of body weight. Regardless of the duration of intervention, both types of application resulted in an increased energy excretion, while food and energy intake was not affected by EGCG. Fecal energy loss was accompanied by an increased fat and nitrogen excretion, which was probably due to an inhibition of digestive enzymes. Fed mice displayed a decreased triglyceride and glycogen content in liver suggesting a reduced absorption of nutrients in the intestine. This was supported by a decreased expression of intestinal fatty acid transporters. However, expression of glucose transporters was increased after short- and medium term application. Furthermore, EGCG attenuated incorporation of naturally 13C-enriched triglycerides into various organs and tissues – particularly liver, visceral and brown adipose tissue, and skeletal muscle. Analysis of 13C-enrichment in breath and measurement of energy expenditure revealed an initial increased fat oxidation, which was switched to an increased carbohydrate oxidation over time. Besides, a combination of oral administration of EGCG and high fat feeding was accompanied by macroscopic and microscopic deleterious changes in liver. These effects were not observed after dietary supplementation of EGCG. Altogether, reduction in body mass and fat mass by EGCG can be explained by a decreased food digestibility leading to various short- and medium-term changes in fat distribution and lipid metabolism.
114

The effects of combinations of a green tea extract and an active ingredient thereof, with standard antiretroviral drugs on SC-1 cells infected with the LP-BM5 virus

Dias, Andreia Sofia Pires January 2008 (has links)
Thesis (MSc.(Anatomy)--Faculty of Health Sciences)-University of Pretoria, 2008.] / Includes bibliographical references.
115

Use of near infrared spectroscopy (NIRS) and spectrophotometric methods in quality control of green rooibos (Aspalathus Linearis) and honeybush (Cyclopia Genistoides)

Botha, Mariza 12 1900 (has links)
Thesis (MSc Food Sc) (Food Science)--University of Stellenbosch, 2005. / Near infrared spectroscopy (NIRS) and UV/Vis spectrophotometric methods were investigated as rapid and/or more economical methods to quantify the major monomeric phenolic compounds, soluble solid content (SSC), total polyphenol content (TPC) and total antioxidant activity (TAA) of green rooibos and Cyclopia genistoides.
116

A Comparative study on protection of Cyclopia spp. (Honeybush), Aspalathus linearis (Rooibos) and Camellia sinensis teas against Aflatoxin B1 induced mutagenesis in the Salmonella Mutagenicity assay : possible mechanisms involved

Van der Merwe, J.D. 03 1900 (has links)
Thesis (Msc Food Sc (Food Science))--University of Stellenbosch, 2005. / Antimutagenic activity of aqueous extracts of fermented and unfermented Cyclopia spp., i.e. C. intermedia, C. subternata, C. genistoides and C. sessiliflora against metabolically activated aflatoxin B1 (AFB1) in the Salmonella mutagenicity assay with tester strain TA100, was compared to that of fermented and unfermented Aspalathus linearis (rooibos) and Camellia sinensis (black, oolong and green) teas. Possible mechanisms involved in in vitro antimutagenic activity of these teas were investigated, i.e. the stabilising effect of the unfermented Cyclopia spp., unfermented rooibos and green tea on rat liver cytochrome P450 in the S9 fraction from Aroclor 1254 treated rats and their modulation of aniline-induced Type II difference spectra in the microsomal fraction. Inhibition of lipid peroxidation in rat liver S9, by the teas, was assessed to determine whether protection against lipid peroxidation may play a role in cytochrome P450 stability in vitro. Correlation of the antimutagenic activity of the teas with their stabilising effect on cytochrome P450 and inhibition of lipid peroxidation, provided insight into possibly related mechanisms. Antimutagenic activity correlated weakly with a decreased stabilising effect of the teas on cytochrome P450 (r = 0.411, P = 0.013) and the inhibition of lipid peroxidation (r = 0.475, P = 0.003). Decreased stability of cytochrome P450 was associated with substantial lipid peroxidation occurring in rat liver S9. Effective inhibition of lipid peroxidation and stabilising of cytochrome P450 in S9 was evident in the presence of the teas, but no correlation (r = 0.018, P = 0.915) existed for the effect of unfermented teas on cytochrome P450 stability with inhibition of lipid peroxidation. Black tea exhibited the highest protection against AFB1-induced mutagenesis and fermented C. intermedia offered the least protection. “Fermentation” resulted in increased antimutagenic activity of Camellia sinensis and rooibos teas, while the antimutagenic activity of Cyclopia spp. decreased with fermentation except for C. genistoides. Unfermented teas significantly (P < 0.05) stabilised cytochrome P450, with rooibos more effective (P < 0.05) than green tea, but similar (P < 0.05) to Cyclopia spp. Green tea demonstrated the highest inhibition of lipid peroxidation, while the inhibition exerted by rooibos was similar (P > 0.05) to unfermented Cyclopia spp., except for C. genistoides exhibiting the least inhibition. Total polyphenol, flavanol and flavonol/flavone contents of the respective teas were correlated with activity in terms of antimutagenicity, stabilising of cytochrome P450 and inhibition of lipid peroxidation. Antimutagenic activity of Cyclopia spp. correlated with its total polyphenol (r = 0.805, P < 0.0001) and flavanol (r = 0.653, P < 0.0001) contents, while a weak negative correlation (r = -0.456, P = 0.026) was observed for the inhibition of lipid peroxidation by unfermented Cyclopia spp. with the flavonol/flavone content. Antimutagenicity of Cyclopia spp. correlated weakly (r = 0.363, P = 0.012) with its hesperidin content. Antimutagenic activity of rooibos tea correlated moderately (r = 0.751, P < 0.005) with its flavonol/flavone content and specifically the flavones orientin (r = 0.674, P < 0.023) and iso-orientin (r = 0.728, P < 0.011). A strong negative correlation (r = -0.918, P < 0.0001) of antimutagenicity of rooibos with its aspalathin content was observed. Antimutagenic activity of Camellia sinensis teas did not correlate with their total polyphenol, flavanol or flavonol/flavone contents. The flavanol content of green tea showed a good, but marginal (P < 0.1) correlation (r = 0.824, P = 0.086) with decreased cytochrome P450 stability. The modulation of aniline-induced Type II binding to microsomal cytochrome P450 by green tea differed significantly (P < 0.05) from the modulation exhibited by rooibos and Cyclopia spp. Flavonoid glycosylation appeared to influence antimutagenic activity, stabilising of cytochrome P450 and modulation of substrate binding of selected phenolic compounds. The present study indicates that rooibos and Cyclopia spp. have in vitro antimutagenic activity against AFB1, suggesting that consumption of these two herbal teas may have beneficial health effects. It is also suggested that stabilising of cytochrome P450 by tea, and interaction of tea constituents with cytochrome P450, may influence their in vitro antimutagenic activity.
117

Influência do chá verde sobre a reatividade vascular em mulheres obesas / Influence of green tea on vascular reactivity in obese women

Débora Cherfan Goulart Nogueira 21 February 2013 (has links)
Fundação Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro / O Chá Verde, derivado das folhas da planta Camellia sinensis, rico em flavonóides, cuja maior concentração é de Epigalocatequina gallato (EGCG), possui efeito termogênico, além de promover a oxidação da gordura corporal, tendo potencial interesse para o tratamento da obesidade, que atinge prevalência alarmante em diversos países no mundo. O objetivo deste estudo foi a avaliação de parâmetros bioquímicos e investigação da função endotelial em mulheres com Índice de Massa Corporal (IMC) entre 30kg/m2 e 40kg/m2, na faixa de 30 e 50 anos, antes e após 03 meses de consumo de chá verde (600mL/dia, equivalente a 114,42mg de EGCG). Todas as 60 pacientes voluntárias foram submetidas à análise das medidas antropométricas (Peso, Altura, Índice de Massa Corporal, Circunferência de Cintura, Circunferência de Quadril, Relação Cintura-Quadril, Pressão Arterial, à análise da bioquímica de rotina (Glicemia e Insulina de jejum, Triglicerídeos, Colesterol Total, HDL-Colesterol, LDL-Colesterol, Teste Oral de Tolerância à Glicose, Hemograma Completo, Proteína C-Reativa), à análise da bioquímica específica para estresse oxidativo e inflamação (Interleucinas 1 e 6, Fator de Necrose Tumoral Alfa, LDL-Oxidado, VCAM Vascular Cell Adhesion Molecule, ICAM Intercellular Adhesion Molecule, e E-Selectina) e à Pletismografia de Oclusão Venosa (variação de fluxo médio máximo durante a Hiperemia Reativa/Fluxo Basal 1 (VQ Hiper) e fluxo após administração de 0,4mg de Nitroglicerina Sublingual/Fluxo Basal 2 (VQ Nitro)). Após os 3 meses (3M) de tratamento houve redução no peso corporal (86,35[83,00-94,25] vs 3M = 86,00[81,50-92,00] Kg, P < 0,05); no IMC (34,02[32,05-35,62] vs 3M = 33,13[32,28-35,05] kg/m2, P < 0,05); na circunferência de cintura (99[93-107] vs 3M = 98[91-105]cm, P < 0,001); na circunferência de quadril (115[110-119] vs 3M = 114[110-117] cm, P < 0,001); na relação cintura-quadril (0,89[0,84-0,93] vs 3M = 0,88[0,83-0,93], P < 0,001); e, na pressão arterial diastólica (75[73-82] vs 3M = 69[67-72] mmHg, P < 0,001); e, melhora significativa no fluxo sanguíneo da VQ Hiper (4,57[3,54-5,01] vs 3M = 5,83[4,46-6,56], P < 0,001); e da VQ Nitro (1,26[1,13-1,38] vs 3M = 1,41[1,25-1,50], P < 0,001). Com o uso do chá verde, 600mL/dia, contendo 114,42mg de EGCG, durante 3 meses observamos a redução de 3% no IMC e a redução da circunferência de cintura e de circunferência de quadril em 1cm; a não modificação do padrão bioquímico, incluindo os marcadores de inflamação e de estresse oxidativo; e, o aumento das vasodilatações endotélio-dependente e endotélio-independente, visualizadas por Pletismografia de Oclusão Venosa Não-Invasiva. / Green tea, derived from the leaves of the plant Camellia sinensis, rich in flavonoids, whose greatest concentration is Epigallocatechin gallato (EGCG), has termogenic effect, and promote fat oxidation, with potential interest for the treatment of obesity, which is reaching alarming prevalence in many countries worldwide. The aim of this study was to evaluate biochemical parameters and endothelial function in women with Body Mass Index (BMI) between 30kg/m2 and 40kg/m2, 30 and 50 years old, before and after 03 months of consumption of green tea (600mL/day, equivalent to 114.42mg of EGCG). All the 60 voluntary patients were submitted to the analyses of anthropometric measures (weight, height, body mass index, waist circumference, hip circumference, waist-hip ratio, blood pressure), to the biochemicalanalysis of routine (fasting glucose and insulin, triglycerides, total cholesterol, HDL-cholesterol, LDL-cholesterol, oral glucose tolerance, hemogram, C-Reactive protein), to the biochemical analysis of specific oxidative stress and inflammation (interleukins 1 and 6, tumor necrosis factor alpha, oxidized LDL, VCAM - Vascular Cell Adhesion Molecule, ICAM - Intercellular Adhesion Molecule and E-selectin) and to venous occlusion plethysmography (variation of maximum average flux during Reactive Hyperemia/Basal 1 Flow (VQ Hiper) and flow after administration of 0,4mg Sublingual Nitroglycerin/Basl 2 Flow (VQ Nitro)).After 03 months (3M) of treatment there was a reduction in body weight (86.35[83.00-94.25] vs 3M = 86.00[81.50-92.00] Kg, P < 0.05); in BMI (34.02[32.05-35.62] vs 3M = 33.13[32.28-35.05] kg/m2, P < 0.05); in waist circumference (99[93-107] vs 3M = 98[91-105]cm, P < 0.001); in hip circumference (115[110-119] vs 3M = 114[110-117] cm, P < 0.001); in waist-hip ration (0.89[0.84-0.93] vs 3M = 0.88[0.83-0.93], P < 0.001); and in diastolic blood pressure (75[73-82] vs 3M = 69[67-72] mmHg, P < 0.001); and, a significant improvement in blood flow of VQ Hiper (4.57[3.54-5.01] vs 3M = 5.83[4.46-6.56], P < 0.001); and in blood flow of VQ Nitro (1.26[1.13-1.38] vs 3M = 1.41[1.25-1.50], P < 0.001). With the use of green tea, 600mL/day, containing 114.42mg of EGCG for 3 months we saw a reduction of 3% in BMI and in the waist and hip circumferences of 1cm. There were no modification of standard biochemical parameters, including markers of inflammation and oxidative stress. There was increased endothelium-dependent and endothelium-independent vasodilation, viewed by noninvasive venous occlusion plethysmography.
118

Efeito da radiação ionizante em chás da planta Camellia sinensis irradiados com diferentes atividades de água / Ionizing radiation effect on teas of Camellia sinensis plant irradiated with different water activities

Gustavo Bernardes Fanaro 12 June 2013 (has links)
O chá é uma das bebidas mais consumidas no mundo. Os chás provenientes da planta Camellia sinensis possuem altos teores de antioxidantes, o que significa que podem ter diversos efeitos benéficos na preservação da saúde. Durante séculos, a humanidade procura formas de conservar melhor e por mais tempo os alimentos que consomem. O processo de irradiação de alimentos é uma técnica amplamente utilizada em todo o mundo e é indicada por diversos órgãos de saúde e sanitários de diversos países. A radiação interage com o material causando dois tipos de efeitos, o efeito direto e o efeito indireto. No efeito direto a radiação interage com a molécula de DNA, causando a quebra dessa molécula, inativando a célula. No efeito indireto, que representa 70% da interação, a radiação quebra a molécula de água presente no meio, em um processo chamado de radiólise, criando uma série de radicais livres que vão interagir com os componentes celulares, levando a morte da célula. Portanto, o objetivo deste trabalho foi estudar os efeitos da radiação gama em dois tipos de chás da planta Camellia sinensis irradiados com diferentes valores de atividade de água. As amostras de chá verde e chá preto tiveram suas Aw ajustadas a três valores (Aw alta, Aw média e Aw baixa). As amostras foram irradiadas em fonte de 60Co nas doses de 0; 1,0; 1,5; 2,0; 2,5; 5,0; 7,5 e 10,0 kGy. As análises utilizadas foram: microbiologia por semeadura de superfície, quantificação de fenólicos totais, análise da atividade antioxidante por ORAC e identificação e quantificação dos principais antioxidantes presente nessas bebidas. Foi possível constatar que quanto maior a quantidade de água livre presente no meio, menor foi a dose para realizar o controle microbiológico. O chá verde mostrou ser um pouco mais suscetível a irradiação com alta Aw do que o chá preto, pois houve variação da quantidade de fenólicos e flavonóides, diminuindo a quantidade desses compostos em algumas doses, mas também houve aumento da quantidade em outras doses. Entretanto em ambos os chás, essas mudanças podem ser consideradas insignificantes, uma vez que não houve diferença da atividade antioxidante em doses de até 10 kGy. A dose de 5,0 kGy foi a dose mínima que garantiu o controle microbiológico e não causou alterações nos parâmetros analisados. / Tea is the most consumed beverage in the world. Teas from Camellia sinensis plant have high levels of antioxidants, which mean that they may have several beneficial effects on health preservation. For centuries, mankind looks for ways to conserve better and for a longer time the food that they eat. The food irradiation process is a largely technique used worldwide, and is recommended by many health agencies and authorities of several countries. The radiation interacts with the material causing two kinds of effects, the direct and the indirect effect. In the direct effect the radiation interacts with the DNA molecule, breaking it, and then inactivates the cell. In the indirect effect, which represents 70% of the interaction, the radiation breaks the water molecule in a process denominated radiolysis, creating a number of free radicals that will interact with the cellular components, leading to the cell death. Therefore, the aim of this work is to study the effects of gamma radiation on two kinds of tea from Camellia sinensis plant irradiated with different water activities. The green tea and black tea samples had their Aw adjusted to three values (high Aw, medium Aw, and low Aw). The samples were irradiated in 60Co source at doses of 0, 1.0, 1.5, 2.0, 2.5, 5.0, 7.5, and 10.0 kGy. The analyses used were: microbiology by plate count, total phenolic compounds quantification, antioxidant activity by ORAC assay, and identification and quantification of main antioxidants in these beverages. It was noted that the greater the quantity of free water present in the medium, the lower was the dose to achieve microbiological control. The green tea showed to be a little more susceptible to irradiation by high Aw once there was more variation in the amount of flavonoids and phenolics than the black tea, decreasing the amount of these compounds in some doses, but increasing the amount in other ones. However in both teas, these changes can be considered insignificant, since there was no difference in antioxidant activity at doses up to 10 kGy. The dose of 5.0 kGy was the minimum dose that secured the microbiological control and had no changes on the parameters analyzed.
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Identification de composés naturels inhibant le virus de l’hépatite C / Identification of naturals compounds inhibiting hepatitis C virus

Sahuc, Marie-Emmanuelle 22 May 2017 (has links)
L’hépatite C est une maladie affectant aujourd’hui 170 millions d’individus dans le monde. Cette maladie est causée par le virus de l'hépatite C (VHC). Les nouveaux traitements récemment mis sur le marché, visant à soigner l’hépatite C, sont très onéreux et donc inaccessibles pour les pays du Sud. De plus, l’utilisation de ces nouvelles molécules engendre l’apparition de mutation de résistance virale responsable de l’échec des traitements pour 5 à 10% des patients. La découverte de nouveaux antiviraux est donc toujours indispensable. Les plantes utilisées en médecine traditionnelle depuis des siècles sont une source de composés bio-actifs très intéressante. L’utilisation de ces plantes ou de composés naturels en complément des molécules utilisées en thérapie classique, permettrait de réduire significativement le coût de ces traitements et de les rendre accessibles à davantage de patients.L’epigallocatéchine-3-gallate (EGCG) et la delphinidine sont des molécules naturelles issues respectivement du thé vert et des fruits rouges. Ces deux molécules inhibent l’étape d’entrée du VHC dans les cellules hépatocytaires. Nous avons montré que l'EGCG et la delphinidine inhibent cette étape virale dans les hépatocytes en déformant les particules et bloquant ainsi leur attachement à la surface cellulaire. Nous nous sommes ensuite intéressés au processus engendrant cette déformation qui est probablement lié à l’agrégation des glycoprotéines d’enveloppe virale.Nous avons procédé au criblage d’extraits bruts de plantes extrêmophiles tunisiennes et mis en évidence que l’extrait brut de rhizome de Juncus maritimus inhibait l’étape de réplication du VHC. Le J. maritimus est une plante fortement présente dans les sols arides en Tunisie mais également sur les côtes françaises. En collaboration avec le laboratoire de Pharmacognosie de Lille et grâce à un fractionnement bioguidé, le principe actif a pu être isolé. Il s’agit du déhydrojuncusol qui inhibe la réplication virale avec une concentration effective médiane de 1,31 µM. De plus, nous avons montré que le déhydrojuncusol pouvait inhiber la réplication de virus présentant des mutations de résistance aux traitements actuels ciblant la protéine virale NS5A. Nous avons cherché à identifier la cible virale du déhydrojuncusol et il semblerait que ce soit également la protéine NS5A.Les résultats obtenus dans cette thèse confortent l’hypothèse que des molécules naturelles pourraient être utilisées dans le traitement de l’hépatite C. / Hepatitis C is a liver disease affecting 170 million people worldwide. This disease is caused by hepatitis C virus (HCV). New treatments, recently marketed, against HCV are very expensive and not really accessible for most-infected patients especially in low-income countries. Moreover, the use of these new molecules generates the emergence of HCV resistant variants responsible for treatment failure for 5 to 10% of the patients. Therefore, the discovery of new antiviral molecules is always needed. Since centuries, plants are used in traditional medicine. They are a very attractive source of bio-active compounds. Plant extracts or natural molecules used in combination with actual therapy, could significantly reduce the cost of these new treatments and render them accessible to more patients.Epigallocatechin-3-gallate (EGCG) and delphinidin are natural molecules derived respectively from green tea and red berries. These two molecules inhibit HCV entry into hepatocyte cells. We have shown that this inhibition is due to a deformation of viral particles by the molecules inducing a blockade of virus attachment to the cell surface. We further investigated the process leading to this deformation, and conclude that it might be related to aggregation of viral envelope glycoproteins.We screened extracts of extremophile plants from Tunisia and showed that the crude extract of Juncus maritimus rhizome inhibited HCV replication step. J. maritimus is a plant present in arid soils in Tunisia but also in French coasts. In collaboration with the Pharmacognosy laboratory of Lille and thanks to a bioguided fractionation, the active compound present in this plant could be isolated. It was identified as dehydrojuncusol, which inhibits viral replication with a half maximal effective concentration of 1.31 &#956;M. We have also shown that dehydrojuncusol is able to inhibit replication of viruses with resistance mutations to current treatments targeting the viral protein NS5A. We have also tried to identify the viral target of dehydrojuncusol, and it seems that the target might also be the NS5A protein.The results obtained in this thesis confirm the hypothesis that natural molecules could be used in the treatment of hepatitis C.
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Influência do chá verde sobre a reatividade vascular em mulheres obesas / Influence of green tea on vascular reactivity in obese women

Débora Cherfan Goulart Nogueira 21 February 2013 (has links)
Fundação Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro / O Chá Verde, derivado das folhas da planta Camellia sinensis, rico em flavonóides, cuja maior concentração é de Epigalocatequina gallato (EGCG), possui efeito termogênico, além de promover a oxidação da gordura corporal, tendo potencial interesse para o tratamento da obesidade, que atinge prevalência alarmante em diversos países no mundo. O objetivo deste estudo foi a avaliação de parâmetros bioquímicos e investigação da função endotelial em mulheres com Índice de Massa Corporal (IMC) entre 30kg/m2 e 40kg/m2, na faixa de 30 e 50 anos, antes e após 03 meses de consumo de chá verde (600mL/dia, equivalente a 114,42mg de EGCG). Todas as 60 pacientes voluntárias foram submetidas à análise das medidas antropométricas (Peso, Altura, Índice de Massa Corporal, Circunferência de Cintura, Circunferência de Quadril, Relação Cintura-Quadril, Pressão Arterial, à análise da bioquímica de rotina (Glicemia e Insulina de jejum, Triglicerídeos, Colesterol Total, HDL-Colesterol, LDL-Colesterol, Teste Oral de Tolerância à Glicose, Hemograma Completo, Proteína C-Reativa), à análise da bioquímica específica para estresse oxidativo e inflamação (Interleucinas 1 e 6, Fator de Necrose Tumoral Alfa, LDL-Oxidado, VCAM Vascular Cell Adhesion Molecule, ICAM Intercellular Adhesion Molecule, e E-Selectina) e à Pletismografia de Oclusão Venosa (variação de fluxo médio máximo durante a Hiperemia Reativa/Fluxo Basal 1 (VQ Hiper) e fluxo após administração de 0,4mg de Nitroglicerina Sublingual/Fluxo Basal 2 (VQ Nitro)). Após os 3 meses (3M) de tratamento houve redução no peso corporal (86,35[83,00-94,25] vs 3M = 86,00[81,50-92,00] Kg, P < 0,05); no IMC (34,02[32,05-35,62] vs 3M = 33,13[32,28-35,05] kg/m2, P < 0,05); na circunferência de cintura (99[93-107] vs 3M = 98[91-105]cm, P < 0,001); na circunferência de quadril (115[110-119] vs 3M = 114[110-117] cm, P < 0,001); na relação cintura-quadril (0,89[0,84-0,93] vs 3M = 0,88[0,83-0,93], P < 0,001); e, na pressão arterial diastólica (75[73-82] vs 3M = 69[67-72] mmHg, P < 0,001); e, melhora significativa no fluxo sanguíneo da VQ Hiper (4,57[3,54-5,01] vs 3M = 5,83[4,46-6,56], P < 0,001); e da VQ Nitro (1,26[1,13-1,38] vs 3M = 1,41[1,25-1,50], P < 0,001). Com o uso do chá verde, 600mL/dia, contendo 114,42mg de EGCG, durante 3 meses observamos a redução de 3% no IMC e a redução da circunferência de cintura e de circunferência de quadril em 1cm; a não modificação do padrão bioquímico, incluindo os marcadores de inflamação e de estresse oxidativo; e, o aumento das vasodilatações endotélio-dependente e endotélio-independente, visualizadas por Pletismografia de Oclusão Venosa Não-Invasiva. / Green tea, derived from the leaves of the plant Camellia sinensis, rich in flavonoids, whose greatest concentration is Epigallocatechin gallato (EGCG), has termogenic effect, and promote fat oxidation, with potential interest for the treatment of obesity, which is reaching alarming prevalence in many countries worldwide. The aim of this study was to evaluate biochemical parameters and endothelial function in women with Body Mass Index (BMI) between 30kg/m2 and 40kg/m2, 30 and 50 years old, before and after 03 months of consumption of green tea (600mL/day, equivalent to 114.42mg of EGCG). All the 60 voluntary patients were submitted to the analyses of anthropometric measures (weight, height, body mass index, waist circumference, hip circumference, waist-hip ratio, blood pressure), to the biochemicalanalysis of routine (fasting glucose and insulin, triglycerides, total cholesterol, HDL-cholesterol, LDL-cholesterol, oral glucose tolerance, hemogram, C-Reactive protein), to the biochemical analysis of specific oxidative stress and inflammation (interleukins 1 and 6, tumor necrosis factor alpha, oxidized LDL, VCAM - Vascular Cell Adhesion Molecule, ICAM - Intercellular Adhesion Molecule and E-selectin) and to venous occlusion plethysmography (variation of maximum average flux during Reactive Hyperemia/Basal 1 Flow (VQ Hiper) and flow after administration of 0,4mg Sublingual Nitroglycerin/Basl 2 Flow (VQ Nitro)).After 03 months (3M) of treatment there was a reduction in body weight (86.35[83.00-94.25] vs 3M = 86.00[81.50-92.00] Kg, P < 0.05); in BMI (34.02[32.05-35.62] vs 3M = 33.13[32.28-35.05] kg/m2, P < 0.05); in waist circumference (99[93-107] vs 3M = 98[91-105]cm, P < 0.001); in hip circumference (115[110-119] vs 3M = 114[110-117] cm, P < 0.001); in waist-hip ration (0.89[0.84-0.93] vs 3M = 0.88[0.83-0.93], P < 0.001); and in diastolic blood pressure (75[73-82] vs 3M = 69[67-72] mmHg, P < 0.001); and, a significant improvement in blood flow of VQ Hiper (4.57[3.54-5.01] vs 3M = 5.83[4.46-6.56], P < 0.001); and in blood flow of VQ Nitro (1.26[1.13-1.38] vs 3M = 1.41[1.25-1.50], P < 0.001). With the use of green tea, 600mL/day, containing 114.42mg of EGCG for 3 months we saw a reduction of 3% in BMI and in the waist and hip circumferences of 1cm. There were no modification of standard biochemical parameters, including markers of inflammation and oxidative stress. There was increased endothelium-dependent and endothelium-independent vasodilation, viewed by noninvasive venous occlusion plethysmography.

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