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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.
1

Investigating the chemopreventive effect of hesperetin, luteolin and cyclooxygenase inhibitors in a mouse model of breast cancer.

January 2012 (has links)
乳腺癌是女性最常見的腫瘤之一,多發生在女性絶經後,並具有雌激素依賴性。芳香化酶(CYP19)是雌激素生物合成過程中的關鍵酶,而芳香化酶抑製劑(AI)則被用於替代治療雌激素依賴性的乳腺癌。然而,AI在降低雌激素水平的同時能夠引起骨質酥鬆。此項研究的目的是找尋AI替代物。 / 黃酮類化合物是一種多酚化合物,廣泛分佈于植物中。我們先前的研究發現二氢黄酮陈皮素能夠抑制芳香化酶的生物活性,并且抑制芳香化酶高表達的乳腺癌生長。在本研究中,我們發現陳皮素在抑制腫瘤生長的同時能夠降低来曲唑引起的骨質流失。木犀草素是另外一種黄酮类化合物,它同樣能夠抑制芳香化酶的活性并減少骨流失。而與陳皮素不同的是,它能夠抑制芳香化酶的表達。在芳香化酶高表達的乳腺癌細胞(MCF-7 aro)中,木犀草素抑制芳香化酶活性的IC50是3 μM。在MCF-7 細胞中,5 μM的木犀草素能夠抑制CYP19 mRNA 的表達,螢光素酶報告實驗顯示木犀草素是通過作用于啟動子I.3和II來抑制CYP19的表達。蛋白印跡實驗表明木犀草素抑制CYP19表達的分子機制可能通過調節JNK信號通路進而減少AP-1的活性來實現。動物實驗結果顯示木犀草素能夠抑制MCF-7aro腫瘤的生長并改善來曲唑引起的骨流失。 / 環氧化酶(COX)是花生四烯酸轉化為前列腺素途徑中的一種關鍵酶。研究發現COX-2在乳腺癌組織中廣泛表達。本實驗研究了COX抑製劑在裸鼠動物模型中對乳腺癌腫瘤的作用機制。研究結果表明塞來昔布和阿司匹林在不影響血液中雌激素水平的情況下抑制乳腺癌腫瘤的生長。蛋白印迹實驗顯示這兩種藥物能夠降低腫瘤中COX-2,Cyclin A和Bcl-xL的表達。miR-98, miR-222和miR-145也能夠被塞來昔布和阿司匹林影響。 / 本研究表明陳皮素,木犀草素及COX抑制劑有潛力成為替代AI的化學治療藥物或共同治療藥物。 / Breast cancer is one of the most prevalent cancers affecting women. The majority of breast tumor growth occurred in the post-menopausal period are estrogen dependent. Aromatase (CYP19) catalyzes the rate-limiting step in the synthetic reaction of estrogen and aromatase inhibitors (AIs) are contemporary treatment for estrogen-positive breast cancer. However, estrogen-lowering drugs may promote osteoporosis. Our objective of this study further identified some alternatives for AIs. / Flavonoids are polyphenolic compounds that are ubiquitously distributed in plants. We have previously found that the flavanone hesperetin can inhibit the activity of aromatase and suppress aromatase-expressing breast tumor growth. In this project, we investigated the potential interaction between hesperetin and the AI letrozole in a mouse model. Our results showed that hesperetin could inhibit the tumor growth and reduce bone loss induced by letrozole. Similarly, another flavonoid luteolin also inhibited aromatase and prevented bone deterioration as observed in this project. In cells stably transfected with CYP19 (MCF-7aro), luteolin inhibited the aromatase activity with an IC50 value of 3μM. In addition, 5μM luteolin significantly reduced CYP19 mRNA expression in MCF-7 cells. Luciferase reporter assay revealed that luteolin could suppress CYP19 transcription at promoter regions I.3 and II. Western analysis illustrated that JNK signaling pathway was involved and deactivation of AP-1 could be the underlying molecular mechanism. Subsequently, we examined the effect in vivo. Our results showed that luteolin could inhibit the MCF-7aro tumor growth and improved bone loss induced by letrozole. / Cyclooxygenase (COX) is an enzyme responsible for the conversion of arachidonic acid into prostaglandins. It is over-expressed in breast cancer tissue and an increased expression of COX-2 was also observed in the xenograft model employed in this project. In the last study we evaluated the importance of COX-2 in breast tumor growth in this model. Our data showed that celecoxib and aspirin could significantly suppress the tumor growth without changing the plasma estrogen level. Western analysis illustrated that COX-2, Cyclin A, Bcl-xL and ER were reduced in celecoxib- and aspirin- treated tumor samples and miR-98, miR-222 and miR-145 were altered by celecoxib or aspirin. / After all, this project demonstrated that hesperetin, luteolin and COX-inhibitors could be potential chemopreventive or co-therapeutic agents. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Li, Fengjuan. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 131-148). / Abstract also in Chinese. / ACKNOWLEDGEMENTS --- p.I / ABSTRACT --- p.II / 摘要 --- p.IV / LIST OF ABBREVIATIONS --- p.V / TABLE OF CONTENTS --- p.VII / CHAPTER 1 --- p.1 / GENERAL INTRODUCTION --- p.1 / Chapter 1.1 --- Types of Breast Cancer --- p.3 / Chapter 1.2 --- Nuclear Receptor Signaling Pathways in Breast Cancer --- p.5 / Chapter 1.3 --- Estrogen and Breast Cancer --- p.7 / Chapter 1.4 --- Estrogen and Bone Health --- p.8 / Chapter 1.5 --- Estrogen Biosynthesis and Aromatase --- p.10 / Chapter 1.6 --- Tissue Specific Promoter for Aromatase Expression --- p.13 / Chapter 1.7 --- Nuclear Receptors and Aromatase Promoter Regulation --- p.15 / Chapter 1.8 --- Signaling Pathway and Aromatase Expression --- p.17 / Chapter 1.9 --- Cell Cycle in Breast Cancer --- p.20 / Chapter 1.10 --- Cell Apoptosis --- p.23 / Chapter 1.11 --- Treatment of breast cancer --- p.25 / Chapter 1.12 --- Phytoestrogens --- p.29 / Chapter 1.13 --- Aim of My Study --- p.32 / CHAPTER 2 --- p.33 / MATERIALS AND METHODS --- p.33 / Chapter 2.1 --- Chemicals and Materials --- p.33 / Chapter 2.1.1 --- Chemicals --- p.33 / Chapter 2.1.2 --- Plasmids --- p.33 / Chapter 2.2 --- Cell Culture --- p.33 / Chapter 2.3 --- Aromatase Activity Assay --- p.34 / Chapter 2.4 --- Quantitative Real Time PCR --- p.36 / Chapter 2.4.1 --- RNA Isolation and cDNA Synthesis --- p.36 / Chapter 2.4.2 --- Quantitative Real Time PCR Assay --- p.37 / Chapter 2.4.3 --- MiRNA Quantitative Real Time PCR Assay --- p.38 / Chapter 2.5 --- Western Blot --- p.39 / Chapter 2.6 --- Measurement of Promoter Activity --- p.41 / Chapter 2.6.1 --- Plasmid Preparation --- p.41 / Chapter 2.6.2 --- Transient Transfection and Dual-Luciferase Assay --- p.42 / Chapter 2.7 --- Electrophoretic Mobility Shift Assay (EMSA) --- p.43 / Chapter 2.7.1 --- Nuclear protein extraction --- p.43 / Chapter 2.7.2 --- Electrophorectic Mobility Shift Assay --- p.44 / Chapter 2.8 --- Animal Experiment Design --- p.45 / Chapter 2.8.1 --- Animal Model for Hesperetin Study --- p.45 / Chapter 2.8.2 --- Animal Model for Luteolin Study --- p.46 / Chapter 2.8.3 --- Animal Model for Cycooxygenase Inhibitors Study --- p.48 / Chapter 2.8.4 --- Serum Estradiol Determination --- p.49 / Chapter 2.8.5 --- Analysis of serum lipoproteins --- p.49 / Chapter 2.8.6 --- Bone Image Acquisition and Region of Interest Selection --- p.50 / Chapter 2.9 --- Statistical Analysis --- p.50 / CHAPTER 3 --- p.51 / The citrus flavonone hesperetin prevents letrozole- induced bone loss in a mouse model of breast cancer --- p.51 / Chapter 3.1 --- Introduction --- p.51 / Chapter 3.2 --- Results --- p.54 / Chapter 3.2.1 --- Murine Body Weight and Liver Weight --- p.54 / Chapter 3.2.2 --- Effect of Hesperetin and Letrozole on Xenograft Growth in Ovariectomized Mice --- p.55 / Chapter 3.2.3 --- Hesperetin Reduced Plasma Estradiol Concentration --- p.58 / Chapter 3.2.4 --- PS2 mRNA Expression in Tumor --- p.59 / Chapter 3.2.5 --- Uterine Wet Weight --- p.60 / Chapter 3.2.6 --- Hesperetin Prevent Bone Deterioration Induced by Letrozole --- p.61 / Chapter 3.3 --- DISCUSSION --- p.63 / CHAPTER 4 --- p.66 / dIETARY FLAVONOID LUTEOLIN ON cyp19 transcription in the breast cancer cells mcf-7 --- p.66 / Chapter 4.1 --- Introduction --- p.66 / Chapter 4.2 --- Results --- p.68 / Chapter 4.2.1 --- Inhibitory Effect of Luteolin on Aromatase Activity --- p.68 / Chapter 4.2.2 --- Luteolin Reduced Aromatase mRNA Expression in MCF-7 Cells --- p.70 / Chapter 4.2.3 --- Effect of Luteolin on Promoter I.3/II Activity of CYP19 in MCF-7 Cells --- p.71 / Chapter 4.2.4 --- The Effect of Luteolin on Truncation CYP19 Gene Reporter Assay --- p.72 / Chapter 4.2.5 --- Luteolin Reduced AP-1 Binding in Promoter I.3/II DNA Fragment --- p.74 / Chapter 4.2.6 --- Inhibitory Effect of Luteolin on Protein Kinase Signaling --- p.76 / Chapter 4.3 --- Discussion --- p.78 / CHAPTER 5 --- p.83 / interaction OF LUTEOLIN and letrozole in a postmenopausal breast cancer model --- p.83 / Chapter 5.1 --- Introduction --- p.83 / Chapter 5.2 --- Results --- p.86 / Chapter 5.2.1 --- Luteolin and letrozole treatment had no effect on mouse body weight and liver weight --- p.86 / Chapter 5.2.2 --- Effect of luteolin and Letrozole on Xenograft Growth in Ovariectomized Mice --- p.88 / Chapter 5.2.3 --- Luteolin reduced plasma estradiol concentration --- p.91 / Chapter 5.2.4 --- Luteolin Counteracted Uterine Weight Reduction under Letrozole Treatment --- p.92 / Chapter 5.2.5 --- Luteolin Prevented Bone Deterioration Induced by Letrozole --- p.93 / Chapter 5.2.6 --- The Effect of Luteolin on Plasma TC and TG --- p.95 / Chapter 5.2.7 --- Luteolin Increased HDL Level and Reduced the Ratio of LDL/HDL --- p.97 / Chapter 5.2.8 --- Effect of Luteolin on Cell Cycle and Apoptotic Protein Expression --- p.99 / Chapter 5.3 --- DISCUSSION --- p.104 / CHAPTER 6 --- p.107 / cyclooxygenase inhibitors suppresse breast tumor growth in NUDE MICE --- p.107 / Chapter 6.1 --- Introduction --- p.107 / Chapter 6.2 --- Results --- p.109 / Chapter 6.2.1 --- Celecoxib and aspirin treatment had no effect on mouse body weight and liver weight --- p.109 / Chapter 6.2.2 --- Effect of celecoxib and aspirin on Xenograft Growth in Ovariectomized Mice --- p.111 / Chapter 6.2.3 --- Celecoxib and aspirin had no effect on plasma estradiol concentration --- p.113 / Chapter 6.2.4 --- Celecoxib and Aspirin Had no Effect on Uterine Weight --- p.114 / Chapter 6.2.5 --- Protein expression of COX-2, Cell cycle-related and cell Apoptotic Genes --- p.115 / Chapter 6.2.6 --- Detection of Related miRNA Expression Level in Tumors --- p.118 / Chapter 6.2.7 --- c-Myc mRNA Expression Level were Regulated in Tumors --- p.121 / Chapter 6.3 --- DISCUSSION --- p.124 / CHAPTER 7 --- p.127 / SUMMARY --- p.127 / REFERENCE --- p.131
2

Optimisation of retention of Mangiferin in Cyclopia Subternata during preparation for drying and storage of green honeybush and development of Nir Spectroscopy Calibration models for rapid quantification of Mangiferin and Xanthone contents

Maicu, Maria Christina 03 1900 (has links)
Thesis (Msc Food Sc (Food Science))--Stellenbosch University, 2008. / Extraction efficiency of soluble solids (SS), total polyphenols (TP) and xanthones (AlCl3 assay) from dried, green Cyclopia subternata, as affected by mass-solvent ratio, extraction time and solvents, was investigated. In addition the effect of solvent composition on extraction of mangiferin and hesperidin was determined. Extraction of 5 g plant material as opposed to 0.5 and 1 g resulted in lower recoveries of SS, TP and xanthones (P<0.05). Extraction of SS and TP increased during the initial 20 min of contact time, where after it remained constant (P>0.05). Water, 33% acetonitrile, ethanol (50, 80 and 100%), methanol (50 and 100%) and 70% acetone were investigated as extraction solvents. Extraction for 30 min with 33% acetonitrile on a steam bath or 50% ethanol at 64°C on a water bath proved to be the most effective for extraction of SS, TP and xanthones, while 33% acetonitrile was most effective in extracting hesperidin from C. subternata. However, 70% acetone was most effective in extracting mangiferin. A poor correlation (r = 0.54) was observed for the total antioxidant activity (TAA) of C. subternata, as determined for water extracts and with the mangiferin content determined by HPLC. A moderate correlation (r = 0.85) was, however, obtained for TAA and TP content. The mangiferin content of green C. subternata can be determined using the aluminium chloride (AlCl3) colorimetric method. A moderate correlation (r = 0.87) was found for the xanthone content of the plant material determined using the AlCl3 colorimetric method and mangiferin content quantified by HPLC (y = 1.2x + 0.54) following extraction with hot water. For extraction using 33% acetonitrile a weaker correlation (r = 0.74; y = 1.3x + 0.87) was found between the xanthone and mangiferin contents. The xanthone content (determined by AlCl3) of the plant material as extracted by the two solvents, correlated well (r = 0.91). Good correlations were also obtained, when comparing extractions with water and 33% acetonitrile, for determination of the SS (0.94) and mangiferin contents (r = 0.97) of the plant material. Near infrared (NIR) spectroscopy was investigated as a rapid and more economical method for prediction of mangiferin and xanthone contents of dried, green C. subternata plant material. NIR spectroscopy calibration models can be used for screening purposes for the mangiferin and (SEP = 0.21 g.100 g-1; r = 0.82) and xanthone (SEP = 0.27 g.100 g-1; r = 0.81) contents. The effect of various pre-drying treatments and storage temperatures on the colour, soluble SS, TP, mangiferin and hesperidin contents of green C. subternata was investigated. By steaming green C. subternata directly after maceration, its colour retention can be improved. Good stability was shown for mangiferin and hesperidin during manufacture and storage of C. subternata.
3

Hesperidin Accumulation during Fruit and Leaf Development in Satsuma Mandarin (Citrus unshiu) / ウンシュウミカンの果実及び葉の発達時におけるヘスペリジンの集積

Inoue, Tsuyoshi 23 September 2016 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第20007号 / 農博第2191号 / 新制||農||1045(附属図書館) / 学位論文||H28||N5016(農学部図書室) / 33103 / 京都大学大学院農学研究科地域環境科学専攻 / (主査)教授 本田 与一, 教授 髙部 圭司, 准教授 坂本 正弘 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM
4

Estudo comparativo da excreção de flavonoides entre indivíduos eutróficos e obesos, após a ingestão de sucos de laranja, cv. Pera e cv. Moro / Comparative study of excretion of flavonoids among eutrophic and obese individuals, after ingestion of orange juice, cv. Pera and cv Moro

Nishioka, Alessandra Harumi 09 April 2019 (has links)
As laranjas e seus derivados, principalmente os sucos, possuem compostos bioativos, tais como os flavonoides, entre eles as flavanonas hesperidina e narirutina, que podem estar relacionados à promoção e benefícios à saúde. A absorção e metabolização de flavonoides podem ser afetadas por diversos fatores como a microbiota e fatores antropométricos, o que pode afetar a sua bioatividade. Assim, o objetivo deste estudo foi comparar o metabolismo e excreção dos flavonoides entre indivíduos eutróficos e obesos após a ingestão de sucos de laranja pasteurizado obtidos das cvs. Pera e Moro. Em um estudo cross-over randomizado 20 voluntárias eutróficas e 10 voluntárias obesas, com idade entre 19 e 40 anos, consumiram em dose única 600 mL de cada suco, que contém as flavanonas narirutina e hesperidina, além das antocianinas no suco Moro. Os metabólitos de flavanonas e de antocianinas foram identificados e quantificados em urina coletada em diferentes períodos de tempo durante 24 horas. Não foi observada diferença significativa na permeabilidade intestinal entre os grupos. Foram detectados e identificados 8 metabólitos de fase II da hesperitina e naringenina, principalmente mono e diglicuronidados e sulfatos, além de três ácidos fenólicos catabólitos de flavanonas formados pela microbiota intestinal, entre elas o ácido hipúrico, ácido protocatecuico e ácido 3-(3-hidroxifenil)-3-hidroxipropiônico. Os ácidos fenólicos foram os metabólitos majoritários recuperados na urina, principalmente o ácido hipúrico. Ainda, os metabólitos de fase II apresentaram maior excreção entre o período de 4-8h e 8-12h (13 a 27% do total de metabólitos excretados). Não foi observada diferença significante (p<0,05) no total de metabólitos de naringenina e hesperitina excretados na urina durante o período de 24 h entre os dois grupos e para os sucos de laranja, nem para o total de metabólitos, provavelmente devido à grande variabilidade interindividual na excreção. Assim, não foi observada diferença entre a metabolização de flavanonas de laranja entre os eutróficos e obesos e nenhuma correlação com os parâmetros antropométricos avaliados. / Oranges and orange juices contain bioactive compounds, such as flavonoids, mainly the flavanones hesperidin and narirutin, which may be related to the promotion and health benefits. The absorption and metabolization of flavonoids can be affected by several factors such as the gut microbiota and anthropometric parameters, which may affect its bioactivity. Thus, the aim of this study was to compare the metabolism and excretion of flavonoids among eutrophic and obese people after ingestion of two pasteurized orange juice obtained from cvs. Pera and Moro. In a randomized cross-over study 20 eutrophic volunteers and 10 obese volunteers, aged 19-40 years, consumed a single dose of 600 mL of each juice. The metabolites of flavanones and anthocyanins were identified and quantified in urine collected at different time points for 24 hours. No significant difference in intestinal permeability was observed between groups. Eight Phase II metabolites of hesperitin and naringenin, mainly mono and diglycerides and sulfates, and three phenolic catabolites of flavanones formed by the gut microbiota were detected and identified, among them hippuric acid, protocatecuic acid and 3- (3-hydroxyphenyl) ) -3-hydroxypropionic acid. Phenolic acids were the major metabolites recovered in urine, mainly hippuric acid. Furthermore, phase II metabolites had greater excretion between the period of 4-8h and 8-12h (13-27% of total metabolites excreted). No significant difference (p <0.05) was observed in the total of naringenin and hesperitin metabolites excreted in the urine during the 24 h period between the two groups, probably due to interindividual variability in excretion. Thus, no difference was observed on metabolism of flavanones between the eutrophic and obese and no correlation was observed with the anthropometric parameters evaluated.
5

Monitoring flavonoidních látek a karotenoidů ve vybraných doplňcích stravy

Hynštová, Veronika January 2014 (has links)
Dietary food supplements are among the most rapidly growing sectors in the food product industry. The majority of consumers trust in the safety and efficacy of these products. For these reasons is a quality control required and analytical methodologies for this must be used. For identification and quantitative analysis four flavonoids diosmin, hesperidin, rutin and troxerutin in food supplements was used HPLC/MS method. For identification and quantitative analysis three carotenoids betacarotene, lutein and zeaxanthin in food supplements was used HPLC/UV/ViS/DAD method. Separation of flavonoids was achieved on the column ZORBAX POROSHELL 120 EC-C18 (50 x 4,6 mm, 2,7 um) and separation of carotenoids on the column ZORBAX SB CN (75 x 4,6 mm, 3,5 um). The amount of flavonoids and carotenoids in tablets and capsules was determined altogether in 12 different commercial preparations.
6

Isolamento e identificação de substâncias provenientes da laranjeira ´Valência` (Citrus sinensis) envolvidas no estímulo e/ou quebra da dormência de estruturas quiescentes de Colletotrichum acutatum, agente causal da podridão floral dos citros / Isolation and identification of substances from sweet orange Valencia (Citrus sinensis) involved in the stimulation and/or dormancy-breaking of quiescent structures of Colletotrichum acutatum, causal agent of citrus postbloom fruit drop

Simone Cristiane Brand 01 February 2012 (has links)
A podridão floral dos citros (PFC), causada por Colletotrichum acutatum, induz a abscisão de frutos jovens, podendo causar perdas de até 100%. A presença de inóculo viável na forma de conídios e/ou apressórios quiescentes na planta justifica a ocorrência generalizada da doença. Em períodos de chuva a PFC é agravada, possivelmente, em função de substâncias lavadas das diferentes partes da planta, as quais contêm metabólitos que estimulam o desenvolvimento do fungo. Diante do exposto, objetivou-se verificar o efeito das águas de lavagem brutas (ALBs) de flores, botões, folhas velhas (FV) e folhas novas (FN) e mistura destas sobre conídios, apressórios e hifas quiescentes de C. acutatum (isolados 61A e 142) in vitro e in vivo e sobre a severidade da PFC, bem como identificar substâncias presentes nas ALBs, exibindo a atividade biológica de interesse. Além disso, buscou-se verificar variações na composição das ALBs. O efeito de compostos voláteis brutos (CVBs) e os identificados a partir de laranjeira Valência (linalol, limoneno, mirceno, nonanal e a mistura destes) sobre o desenvolvimento do patógeno também foi avaliado. Todas as frações das ALBs estimularam a germinação dos conídios do fungo, sendo que a ALB de flores apresentou o maior estímulo para ambos os isolados. Para apressórios quiescentes (isolado 61A), o maior estímulo foi verificado nos tratamentos com ALBs de botões e da mistura e para conídios no tratamento mistura. Os maiores valores para comprimento do tubo germinativo foram observados nos tratamentos mistura, FN e botões. Para as estruturas quiescentes, o efeito das ALBs foi mais significativo para o isolado 142. Não foi observado efeito das ALBs sobre o micélio quiescente. Houve estímulo da germinação de conídios e ramificação de hifas in vivo, principalmente, em resposta ao tratamento com ALB de botões. A aplicação da ALB da mistura em flores resultou em maior severidade da PFC. Por sua vez, os CVBs apresentaram efeito inibitório. A exposição do isolado 61A aos voláteis (CVs) linalol, nonanal e mistura, resultou em germinação apenas na menor dose. O mirceno manteve a germinação semelhante a testemunha em todas as doses testadas, assim como limoneno nas doses de 0,005 a 0,25 µL mL-1. Todos os voláteis reduziram o comprimento do tubo germinativo. Para o isolado 142, houve redução em todas as variáveis para todas as doses dos CVs. Houve variações na composição das ALBs nas diferentes coletas, o que explica em parte a variação na capacidade de estímulo em alguns testes. Na ALB de flores, identificou-se a presença de cafeína, dos flavonóides glicosilados hesperidina e naringina, além de compostos glicosilados e peptídeos. Nas partes vegetais de laranjeira Valência foram identificados 54 CVs. As ALBs apresentam efeito estimulatório sobre conídios e apressórios quiescentes de C. acutatum in vitro e in vivo, bem como sobre a severidade da PFC. Os CVs linalol, limoneno, mirceno, nonanal e a mistura destes são, de forma geral, inibitórios ao desenvolvimento de C. acutatum. / The postbloom fruit drop of citrus (PFDC), caused by Colletotrichum acutatum, induces abscission of young fruits, and it may cause losses up to 100%. The presence of viable inoculum in the form of conidia and/or quiescent appressoria on the plant justifies the widespread occurrence of the disease. Under rain, the PFDC is increased, possibly due to substances washed from different parts of the plant, which contain metabolites that stimulate the development of the fungus. Therefore, we aimed to determine the effect of watery washing (WWs) of flowers, flower buds, old leaves (OL) and young leaves (YL) and the mixture of them on quiescent conidia and hyphae of C. acutatum (isolates 61A and 142) in vitro and in vivo and on the severity of the PFDC, and to identify substances in the WWs, exhibiting the biological activity of interest. In addition, variations in the composition of WWs were determinated. The effect of crude volatile compounds (CVCs) and those identified from Valencia sweet orange (linalool, limonene, myrcene, nonanal and the mixture of them) on the development of the pathogen was also evaluated. All fractions of WWs stimulated spore germination, and the flower WW exhibited the highest effect for both isolates. For quiescent appressoria (isolate 61A), the highest stimulus was observed in treatments with WWs from flower buds and the mixture and for quiescent conidia in the treatment mixture. The highest values for germ tube length were observed on the treatments mixture, YL and flower buds. For the quiescent structures, the effect of WWs was more significant for isolate 142. There was no effect of WWs on the quiescent mycelium. There was stimulation of conidia germination and hyphal branching in vivo in response mainly to treatment with WW from flower buds. The application of the mixture of WW in flowers resulted in higher severity of the PFDC. On the other hand, the CVCs showed inhibitory effect. Exposure of the isolate 61A to the volatiles (VCs) linalool, nonanal and the mixture of them, resulted in germination only at the lowest concentration. The germination on myrcene was similar to control at all doses tested as well as on limonene at doses from 0.005 to 0.25 mL mL-1. All volatiles reduced the length of the germ tube. In the case of isolate 142, a reduction in all variables for all concentration of VCs was observed. There were changes in the composition of WWs based upon times of harvesting, which partly explains the variations observed in the ability to stimulate the structures in some experiments. In flower WWs, we identified the presence of caffeine, the flavonol glycosides hesperidin and naringin, glycosylated compounds and peptides. In the plant parts of sweet orange \'Valencia\' were identified 54 VCs. The WWs have stimulatory effect on quiescent conidia and appressoria of C. acutatum in vitro and in vivo as well as in the severity of the PFDC. The VCs linalool, limonene, myrcene, nonanal and the mixture of them are, in general, inhibitory to the development of C. acutatum.
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Isolamento e identificação de substâncias provenientes da laranjeira ´Valência` (Citrus sinensis) envolvidas no estímulo e/ou quebra da dormência de estruturas quiescentes de Colletotrichum acutatum, agente causal da podridão floral dos citros / Isolation and identification of substances from sweet orange Valencia (Citrus sinensis) involved in the stimulation and/or dormancy-breaking of quiescent structures of Colletotrichum acutatum, causal agent of citrus postbloom fruit drop

Brand, Simone Cristiane 01 February 2012 (has links)
A podridão floral dos citros (PFC), causada por Colletotrichum acutatum, induz a abscisão de frutos jovens, podendo causar perdas de até 100%. A presença de inóculo viável na forma de conídios e/ou apressórios quiescentes na planta justifica a ocorrência generalizada da doença. Em períodos de chuva a PFC é agravada, possivelmente, em função de substâncias lavadas das diferentes partes da planta, as quais contêm metabólitos que estimulam o desenvolvimento do fungo. Diante do exposto, objetivou-se verificar o efeito das águas de lavagem brutas (ALBs) de flores, botões, folhas velhas (FV) e folhas novas (FN) e mistura destas sobre conídios, apressórios e hifas quiescentes de C. acutatum (isolados 61A e 142) in vitro e in vivo e sobre a severidade da PFC, bem como identificar substâncias presentes nas ALBs, exibindo a atividade biológica de interesse. Além disso, buscou-se verificar variações na composição das ALBs. O efeito de compostos voláteis brutos (CVBs) e os identificados a partir de laranjeira Valência (linalol, limoneno, mirceno, nonanal e a mistura destes) sobre o desenvolvimento do patógeno também foi avaliado. Todas as frações das ALBs estimularam a germinação dos conídios do fungo, sendo que a ALB de flores apresentou o maior estímulo para ambos os isolados. Para apressórios quiescentes (isolado 61A), o maior estímulo foi verificado nos tratamentos com ALBs de botões e da mistura e para conídios no tratamento mistura. Os maiores valores para comprimento do tubo germinativo foram observados nos tratamentos mistura, FN e botões. Para as estruturas quiescentes, o efeito das ALBs foi mais significativo para o isolado 142. Não foi observado efeito das ALBs sobre o micélio quiescente. Houve estímulo da germinação de conídios e ramificação de hifas in vivo, principalmente, em resposta ao tratamento com ALB de botões. A aplicação da ALB da mistura em flores resultou em maior severidade da PFC. Por sua vez, os CVBs apresentaram efeito inibitório. A exposição do isolado 61A aos voláteis (CVs) linalol, nonanal e mistura, resultou em germinação apenas na menor dose. O mirceno manteve a germinação semelhante a testemunha em todas as doses testadas, assim como limoneno nas doses de 0,005 a 0,25 µL mL-1. Todos os voláteis reduziram o comprimento do tubo germinativo. Para o isolado 142, houve redução em todas as variáveis para todas as doses dos CVs. Houve variações na composição das ALBs nas diferentes coletas, o que explica em parte a variação na capacidade de estímulo em alguns testes. Na ALB de flores, identificou-se a presença de cafeína, dos flavonóides glicosilados hesperidina e naringina, além de compostos glicosilados e peptídeos. Nas partes vegetais de laranjeira Valência foram identificados 54 CVs. As ALBs apresentam efeito estimulatório sobre conídios e apressórios quiescentes de C. acutatum in vitro e in vivo, bem como sobre a severidade da PFC. Os CVs linalol, limoneno, mirceno, nonanal e a mistura destes são, de forma geral, inibitórios ao desenvolvimento de C. acutatum. / The postbloom fruit drop of citrus (PFDC), caused by Colletotrichum acutatum, induces abscission of young fruits, and it may cause losses up to 100%. The presence of viable inoculum in the form of conidia and/or quiescent appressoria on the plant justifies the widespread occurrence of the disease. Under rain, the PFDC is increased, possibly due to substances washed from different parts of the plant, which contain metabolites that stimulate the development of the fungus. Therefore, we aimed to determine the effect of watery washing (WWs) of flowers, flower buds, old leaves (OL) and young leaves (YL) and the mixture of them on quiescent conidia and hyphae of C. acutatum (isolates 61A and 142) in vitro and in vivo and on the severity of the PFDC, and to identify substances in the WWs, exhibiting the biological activity of interest. In addition, variations in the composition of WWs were determinated. The effect of crude volatile compounds (CVCs) and those identified from Valencia sweet orange (linalool, limonene, myrcene, nonanal and the mixture of them) on the development of the pathogen was also evaluated. All fractions of WWs stimulated spore germination, and the flower WW exhibited the highest effect for both isolates. For quiescent appressoria (isolate 61A), the highest stimulus was observed in treatments with WWs from flower buds and the mixture and for quiescent conidia in the treatment mixture. The highest values for germ tube length were observed on the treatments mixture, YL and flower buds. For the quiescent structures, the effect of WWs was more significant for isolate 142. There was no effect of WWs on the quiescent mycelium. There was stimulation of conidia germination and hyphal branching in vivo in response mainly to treatment with WW from flower buds. The application of the mixture of WW in flowers resulted in higher severity of the PFDC. On the other hand, the CVCs showed inhibitory effect. Exposure of the isolate 61A to the volatiles (VCs) linalool, nonanal and the mixture of them, resulted in germination only at the lowest concentration. The germination on myrcene was similar to control at all doses tested as well as on limonene at doses from 0.005 to 0.25 mL mL-1. All volatiles reduced the length of the germ tube. In the case of isolate 142, a reduction in all variables for all concentration of VCs was observed. There were changes in the composition of WWs based upon times of harvesting, which partly explains the variations observed in the ability to stimulate the structures in some experiments. In flower WWs, we identified the presence of caffeine, the flavonol glycosides hesperidin and naringin, glycosylated compounds and peptides. In the plant parts of sweet orange \'Valencia\' were identified 54 VCs. The WWs have stimulatory effect on quiescent conidia and appressoria of C. acutatum in vitro and in vivo as well as in the severity of the PFDC. The VCs linalool, limonene, myrcene, nonanal and the mixture of them are, in general, inhibitory to the development of C. acutatum.
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O efeito da ingestão de hesperidina sobre a modulação da resposta inflamatória e nível de perda óssea em camundongos com doença periodontal induzida /

Ramadan, Dania. January 2020 (has links)
Orientador: Luis Carlos Spolidorio / Resumo: O objetivo do estudo foi avaliar o efeito da hesperidina(Hesp) sobre a periodontite experimental induzida por injeção de LPS de E. coli em camundongos. 50 camundongos BALB/c foram submetidos a diferentes tratamentos: dieta convencional, dieta enriquecida com hesperidina (25 e 50 mg/kg de peso corporal/dia) e dieta com naproxeno 10mg/kg de peso corporal/dia. Após 30 dias de suplementação os animais foram submetidos a periodontite induzida pela injeção bilateral de Escherichia coli 3x/semana por 4 semanas. Avaliou-se o peso corporal, consumo alimentar e energético ao longo de todo período experimental. Depois de 3 dias da última injeção de LPS os animais foram eutanasiados, coletados fígado e maxila e realizada a análise microscópica do fígado, quantificação de perda óssea por micro-Ct, análise microscópica e estereométrica dos maxilares, perfil de citocinas pró e anti-inflamatórias por imunoensaio multiplex e avaliação da atividade de mieloperoxidase (MPO). In vitro foi avaliada a viabilidade celular por MTT e avaliação da proliferação celular através do método de AlamarBlue®, em cultura de fibroblastos L929 em 1,3 e 7 dias. Ao final do experimento os animais que consumiram ração enriquecida com hesperidina ou naproxeno apresentaram ganho de peso e consumo alimentar e energético semelhante ao grupo controle. Na análise microscópica do fígado não foram encontradas alterações hepáticas. O micro-CT revelou significante aumento da perda óssea no grupo LPS, no qual foi prevenida pe... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aim of the study was to evaluate the effect of hesperidin(Hesp) on experimental periodontitis induced by injection of E. coli LPS in mice. 50 BALB /c mice were submitted to different treatments: conventional diet, enriched diet with hesperidin (25 and 50 mg / kg of body weight / day) and diet with naproxen 10 mg / kg of body weight / day. After 30 days of supplementation, the animals were submitted to periodontitis induced by bilateral injection of Escherichia coli 3x / week for 4 weeks. Body weight, food and energy consumption were evaluated throughout the experimental period. After 3 days of the last LPS injection, the animals were euthanized, liver and maxilla were collected and microscopic analysis of the liver was carried out, quantification of bone loss by micro-Ct, microscopic and stereometric analysis of the jaws, pro and anti-inflammatory cytokine profile by multiplex immunoassay and evaluation of myeloperoxidase (MPO) activity. In vitro cell viability was evaluated by MTT and evaluation of cell proliferation using the AlamarBlue method, in culture of L929 fibroblasts in 1.3 and 7 days. At the end of the experiment, the animals that consumed enriched food with hesperidin or naproxen showed weight gain and food and energy consumption similar to the control group. Microscopic analysis of the liver showed no liver abnormalities. The micro-CT revealed a significant increase in bone loss in the LPS group, in which it was prevented by hesperidin or naproxen. The stereo... (Complete abstract click electronic access below) / Mestre
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Efeito protetor da diosmina e hesperidina na nefrotoxidade induzida pela anfotericina B / Protective effect of diosmin and hesperidin in nephrotocicity by amphotericin B

Schlottfeldt, Fabio dos Santos 21 May 2014 (has links)
A lesão renal aguda LRA induzida pela anfotericina B (Anf-B), um antibiótico poliênico isolado do actiniomiceto Streptomyces nodus, ocorre após alguns dias do início da terapia medicamentosa. Os sinais clínicos característicos são acidose, hipocalemia, depleção de magnésio, sódio e poliúria, resultantes da vasoconstrição renal com redução do fluxo sanguíneo renal (FSR), da taxa de filtração glomerular (TFG) e toxicidade direta nas células epiteliais tubulares com geração de espécies reativas de oxigênio (EROs). A diosmina e hesperidina (DH) são flavonoides com propriedades antioxidantes e anti-inflamatórias. Esse estudo investigou a ação renoprotetora do pré-condicionamento com diosmina e hesperidina em ratos submetidos à toxicidade renal pela Anf-B. Foram utilizados ratos Wistar, adultos e machos distribuídos nos grupos: Salina (controle, 3ml/kg de solução fisiológica 0,9%, salina, intraperitoneal-i.p., uma vez ao dia, cinco dias); DH (50mg/kg de DH na água de bebedouro, dez dias); Anf-B (15mg/kg, i.p. uma vez ao dia, cinco dias); Anf-B+DH (pré-medicação com a solução de DH em água de bebedouro dez dias e a partir do sexto dia do protocolo, Anf-B, 1 vez dia, i.p., 5 dias,). Foram avaliadas a função renal função renal (clearance de creatinina-Clcr, método de Jaffé), as frações de excreção de sódio, potássio e magnésio-FENa, K por meio do método de eletrodo íon seletivos e Mg por Mg por método colorimétrico a lesão oxidativa (peróxidos-PU, FOX-2 e substâncias reativas com o ácido tiobarbitúrico-TBARS urinários). O tratamento com Anf-B resultou em quadro de lesão renal aguda com redução do Clcr, elevação do fluxo urinário, da FENa, da FEK e da FEMg, com elevação de PU e TBARs urinários. O pré-condicionamento com DH demostrou efeito renoprotetor por meio da elevação do Clcr e redução das FENa, FEMg e FEK, além de demonstrar proteção antioxidante confirmada pela redução de metabólitos oxidativos. / The acute kidney inury (AKI) induced by amphotericin B (Amp-B), an antibiotic polyenic group isolated of the actinomycete Streptomyces nodus, occurs after some days of the beginning of drug therapy. Clinical manifestations include acidosis, hypokalemia, magnesium and sodium wasting and polyuria, resulting from renal vasoconstriction with decrease in blood flow, glomerular filtration rate (GFR) and direct toxicity in tubular cells with liberating reactive oxygen species (ROS). Diosmin and hesperidin (DH) are flavonoids with antioxidant and antiinflamatory properties. This study investigated the renoprotective effect of DH in rats submitted to the toxicity by Amp-B. Adult male wistar rats were used and divided in the following groups: Saline (control, 3ml/kg of NaCl 0,9% intraperitoneal (i.p.), once a day, for 5 days); DH (50mg/kg in drinking water, 10 days); Amp-B (15mg/kg, i.p., once a day, 5 days); Amp-B+DH (DH in drinking water, 10 days, from the sixth day, 15mg/kg of Amp-B, i.p., 5 days). Renal function (creatinine clearance-crCl, Jaffé method), sodium, potassium and magnesium excretion fraction, (FENa, FEK,) through selective ion method and FEMg by colorimetric method, oxidative injury (urinary peroxides-FOX-2, thiobarbituric acid reactive substances-TBARS) were evaluated. Amp-B induced AKI with reduction in crCl and increment in FENA, FEK, FEMg, UP and TBARS. The pre-treatment with DH confirmed a renoprotective effect through by increasing GFR and decreasing FENa, FEK, FEMg. In addition, the antioxidant protection was confirmed by reduction of oxidative metabolites by DH.
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ESTUDO DA ASSOCIAÇÃO ENTRE HESPERIDINA E ANFOTERICINA EM DANOS HEPÁTICO E RENAL E NAS OXIDAÇÕES BIOQUÍMICAS

Manente, Francine Alessandra 18 February 2013 (has links)
Made available in DSpace on 2017-07-21T14:13:09Z (GMT). No. of bitstreams: 1 Francine Alessandra Manente.pdf: 1212792 bytes, checksum: 5c5b36ad0ca624ee36b65879663b0362 (MD5) Previous issue date: 2013-02-18 / Amphotericin B (AmB) is drug "gold standard" for the treatment of invasive fungal infections since 1960. However, amphotericin B has high toxicity, which manifests itself most commonly in the kidneys (nephrotoxicity) and less frequently in the liver (liver toxicity). It is known since 1985 that self-oxidation of amphotericin B gives different forms of reactive oxidative species and these are responsible in part by toxicity. An antioxidant, such as hesperidin and rutin, could contribute, through the reduction of oxidative stress, and to protect against renal injury generated by ischemia. This fact and the involvement of amphotericin B in the generation of free radicals make it interesting to evaluate the effect of hesperidin, rutin and amphotericin B (alone or associated) against reactive oxygen species and free radicals, as well as the study of the same models in toxicity . In testing the antifungal combination with hesperidin showed synergism. In tests oxidative systems, opposite the ABTS+, the hesperidin showed IC50= 0,0044mg/mL, rutin IC50=0,0023mg/mL and amphotericin B IC50=0,0124mg/mL (isolated), IC50=0,0003mg/mL (associated with hesperidin) and IC50=0,0014mg/mL (associated with rutin). In the DPPH assay only rutin was action. Front HOCl, hesperidin showed IC50=0,0109, rutin IC50=0,0025 and amphotericin B showed IC50=0,0056 (isolated) IC50=0,0023mg/mL (associated with hesperidin) and IC50=0,0036 (associated with rutin). In the trial with O2 the samples were not effective. In inhibition kinetics MPO/H2O2/Guaiacol only rutin promote inhibition. Front to erythrocytes, amphotericin promoted lysis in a dose-dependent manner. HUVEC cells using the associations decreased cell viability. However, in the toxicity test with Artemia salina associated samples were able to lower the toxicity of amphotericin B. To conclude, in tests with animals amphotericin B caused leukopenia, monopenia generated and renal damage, which can be reversed using hesperidin in combination. With these results, we suggest that the combination of a natural product with amphotericin B could decrease the toxicity caused by this antinfúngico, and concomitant use could be promising. / A anfotericina B (AmB) é fármaco "padrão ouro" para o tratamento de infecções fúngicas invasivas desde 1960. Entretanto, a anfotericina B apresenta elevada toxicidade, que se manifesta mais freqüentemente nos rins (nefrotoxicidade) e com menor frequência no fígado (hepatotoxicidade). É sabido, desde 1985, que a auto-oxidação da anfotericina B origina diferentes formas de espécies reativas oxidativas e estas seriam responsáveis, em parte, pela toxicidade. Agentes antioxidantes, tais como a hesperidina e rutina, poderiam contribuir, por meio do decréscimo do estresse oxidativo, para a proteção renal e contra a injúria gerada pela isquemia. Tal fato e o envolvimento da anfotericina B na geração de radicais livres tornam interessante a avaliação do efeito da hesperidina, rutina e anfotericina B (isoladamente ou associadas) frente a espécies reativas do oxigênio e radicais livres, bem como o estudo das mesmas em modelos de toxicidade. No teste antifúngico a associação com a hesperidina mostrou sinergismo. Nos testes em sistemas oxidativos, frente ao ABTS+, a hesperidina apresentou IC50= 0,0044mg/mL, a rutina IC50=0,0023mg/mL e a anfotericina B IC50=0,0124mg/mL (isolada), IC50=0,0003mg/mL (associada à hesperidina) e IC50=0,0014mg/mL (associada à rutina). No ensaio do DPPH apenas a rutina mostrou ação. Frente ao HOCl, a hesperidina apresentou IC50=0,0109, a rutina IC50=0,0025 e a anfotericina B apresentou IC50=0,0056 (isolada), IC50=0,0023mg/mL (associada com a hesperidina) e IC50=0,0036 (associada com a rutina). No ensaio com o O2 - as amostras não foram efetivas. Na inibição da cinética da MPO/H2O2/Guaiacol somente a rutina promoveu inibição. Frente aos eritrócitos, a anfotericina promoveu lise de modo dose-dependente. Utilizando as células HUVEC, as associações diminuíram a viabilidade celular. Entretanto, no ensaio de toxicidade com a Artemia salina as amostras associadas foram capazes de diminuir a toxicidade da anfotericina B. Para finalizar, nos testes com os animais a anfotericina B causou leucopenia, monopenia e gerou dano renal, o qual pode ser revertido utilizando a hesperidina em associação. Com estes resultados pode-se sugerir que a associação de um produto natural com a anfotericina B poderia diminuir a toxicidade causada por este antinfúngico, sendo que sua utilização concomitante poderá ser promissora. Palavras-chave: hesperidina, anfotericina B, rutina, estresse oxidativo, citotoxicidade, nefrotoxicidade.

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