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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

Avaliação do estado nutricional, ingestão de antioxidante e extensão da lesão intestinal em pacientes portadores de colte ulcerativa

Urbano, Ana Paula Signori [UNESP] 23 February 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:25:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-23Bitstream added on 2014-06-13T19:53:36Z : No. of bitstreams: 1 urbano_aps_me_botfm.pdf: 458359 bytes, checksum: b614918f7318018613922000909872d9 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / As doenças inflamatórias intestinais são consideradas um dos grandes problemas da população moderna, uma vez que geram repercussões importantes na qualidade de vida de seus portadores, acarretando alterações no âmbito social, psicológico e profissional. Embora ainda sem etiologia definida, existem evidências apontando o estresse oxidativo como marca importante na patogênese da Colite Ulcerativa (CU). O objetivo principal deste estudo foi avaliar o estado nutricional, a ingestão de antioxidantes e a extensão da lesão intestinal em portadores de CU em remissão e/ou atividade leve. Trata-se de um estudo transversal, onde foi aplicado formulário específico, com dados socioeconômicos, curso clínico da doença e exames bioquímicos. Para determinação do estado nutricional foram mensurados: peso, altura e índice de massa corporal (IMC), circunferência do braço (CB), dobra cutânea tricipital (DCT) e circunferência muscular do braço (CMB), espessura do músculo adutor do polegar (EMAP) e, a partir da bioimpedância foram mensurados massa gorda (MG), massa magra (MM), massa celular corporal (MCC) e ângulo de fase (AF). Para avaliação da ingestão diária de nutrientes foram aplicados três Recordatórios de 24 horas em dias alternados. Os dados foram apresentados em média e desvio padrão e mediana e percentis 25 e 75. Para a comparação entre os grupos, foram utilizados os testes Mann-Whitney (2 grupos) e Kruskal-Wallis/teste de Tukey (mais de 2 grupos). A regressão logística foi utilizada para verificar associação entre extensão da lesão e consumo de nutrientes e entre extensão da lesão e estado nutricional. Foi considerado nível de significancia de 5% ou valor de p correspondente. Foram avaliados 59 pacientes (48,14±13,95 anos) acompanhados em ambulatório de hospital de ensino, sendo que 53,3% eram mulheres. Os resultados mostraram que, história prévia... / Inflammatory bowel disease has a high rate, high prevalence and negative impact on quality of life for economically active patients. Although the pathogenesis disease appears to be multifactorial (such as environmental, genetic and immunologic), a common denominator to most of the proposed mechanisms is oxidative stress. The aim of this study was to evaluate nutritional status, dietary antioxidant intake in Ulcerative Colitis (UC) patients under remission followed in an academic ambulatory. This is a cross-sectional study, where variables such disease extension (distal, left hemicolitis, pancolitis), remission period, gender, age, socio economic, biochemical blood tests were recorded. Disease degrees were assessed consulting colonoscopy results. Dietary intake was evaluated by 3 interviews using 24 recalls method. Nutritional status was studied using anthropometry and bioimpedance procedures. Mann-Whitney, Kruskal-Wallis and Tukey tests were used to compare groups. Logistic regression and Pearson tests were used to examine association and correlations. The mean age of 59 patients was 48.1 years (SD, 13.95) and 53.3% were women. Prior history of distal, left hemicolitis and pancolitis was present in 44.7%, 18.6% and 37.3% of patients, respectively. Third three (55.9%) were classified as overweight/obesity, 24 (40.7%) as eutrophic and 2 (3.4%) as underweighted, according to Body Mass Index (BMI). BMI was positively correlated with α1-acid glycoprotein (r = 0.36, p <0.05), indicating a direct relationship between excess weight and chronic inflammation in these patients, although in remission. Erythrocyte sedimentation rate was inversely correlated with the thickness of the adductor pollicis muscle (TAPM) and phase angle (PA), suggesting that the prognosis worsens accord to acute inflammatory status and to decreasing of muscle mass. That statement was confirmed by the followings: indirect... (Complete abstract click electronic access below)
2

Avaliação do estado nutricional, ingestão de antioxidante e extensão da lesão intestinal em pacientes portadores de colte ulcerativa /

Urbano, Ana Paula Signori. January 2011 (has links)
Resumo: As doenças inflamatórias intestinais são consideradas um dos grandes problemas da população moderna, uma vez que geram repercussões importantes na qualidade de vida de seus portadores, acarretando alterações no âmbito social, psicológico e profissional. Embora ainda sem etiologia definida, existem evidências apontando o estresse oxidativo como marca importante na patogênese da Colite Ulcerativa (CU). O objetivo principal deste estudo foi avaliar o estado nutricional, a ingestão de antioxidantes e a extensão da lesão intestinal em portadores de CU em remissão e/ou atividade leve. Trata-se de um estudo transversal, onde foi aplicado formulário específico, com dados socioeconômicos, curso clínico da doença e exames bioquímicos. Para determinação do estado nutricional foram mensurados: peso, altura e índice de massa corporal (IMC), circunferência do braço (CB), dobra cutânea tricipital (DCT) e circunferência muscular do braço (CMB), espessura do músculo adutor do polegar (EMAP) e, a partir da bioimpedância foram mensurados massa gorda (MG), massa magra (MM), massa celular corporal (MCC) e ângulo de fase (AF). Para avaliação da ingestão diária de nutrientes foram aplicados três Recordatórios de 24 horas em dias alternados. Os dados foram apresentados em média e desvio padrão e mediana e percentis 25 e 75. Para a comparação entre os grupos, foram utilizados os testes Mann-Whitney (2 grupos) e Kruskal-Wallis/teste de Tukey (mais de 2 grupos). A regressão logística foi utilizada para verificar associação entre extensão da lesão e consumo de nutrientes e entre extensão da lesão e estado nutricional. Foi considerado nível de significancia de 5% ou valor de p correspondente. Foram avaliados 59 pacientes (48,14±13,95 anos) acompanhados em ambulatório de hospital de ensino, sendo que 53,3% eram mulheres. Os resultados mostraram que, história prévia... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Inflammatory bowel disease has a high rate, high prevalence and negative impact on quality of life for economically active patients. Although the pathogenesis disease appears to be multifactorial (such as environmental, genetic and immunologic), a common denominator to most of the proposed mechanisms is oxidative stress. The aim of this study was to evaluate nutritional status, dietary antioxidant intake in Ulcerative Colitis (UC) patients under remission followed in an academic ambulatory. This is a cross-sectional study, where variables such disease extension (distal, left hemicolitis, pancolitis), remission period, gender, age, socio economic, biochemical blood tests were recorded. Disease degrees were assessed consulting colonoscopy results. Dietary intake was evaluated by 3 interviews using 24 recalls method. Nutritional status was studied using anthropometry and bioimpedance procedures. Mann-Whitney, Kruskal-Wallis and Tukey tests were used to compare groups. Logistic regression and Pearson tests were used to examine association and correlations. The mean age of 59 patients was 48.1 years (SD, 13.95) and 53.3% were women. Prior history of distal, left hemicolitis and pancolitis was present in 44.7%, 18.6% and 37.3% of patients, respectively. Third three (55.9%) were classified as overweight/obesity, 24 (40.7%) as eutrophic and 2 (3.4%) as underweighted, according to Body Mass Index (BMI). BMI was positively correlated with α1-acid glycoprotein (r = 0.36, p <0.05), indicating a direct relationship between excess weight and chronic inflammation in these patients, although in remission. Erythrocyte sedimentation rate was inversely correlated with the thickness of the adductor pollicis muscle (TAPM) and phase angle (PA), suggesting that the prognosis worsens accord to acute inflammatory status and to decreasing of muscle mass. That statement was confirmed by the followings: indirect... (Complete abstract click electronic access below) / Orientador: Ana Lucia dos Anjos Ferreira / Coorientador: Lígia Yukie Sassaki / Banca: Lígia Araújo Martini / Banca: Maria Antonieta de Barros Leite Carvalhaes / Mestre
3

Protective effect of dietary antioxidants and plant extracts on acute inflammation and hepatotoxicity in vitro

El-Saadany, Mohamed Abdel Meged Marawan January 2009 (has links)
Dietary antioxidants are believed to play an important role in the prevention and treatment of a variety of diseases associated with oxidative stress. Although there is a wide range of dietary antioxidants, the bulk of the research to date has been focused on the nutrient antioxidants vitamin C, E, and carotenoids. Certain relatively uncommon antioxidants such as lipoic acid (LA), and phenolic compounds such as (-)-epicatechin (EC), (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECG), and (-)-epigallocatechin gallate (EGCG), have not been extensively investigated although they may exert greater antioxidant potency than that of carotenoids and vitamins. Extracts from selected plants and plant byproducts may represent rich sources for one or more of such antioxidants and therefore exhibit higher effects than a single antioxidant due to the synergistic effects produced between such antioxidants. However, in the last decade a number of epidemiological, animal and in vitro studies have suggested a protective and therapeutic potency of these antioxidants in a broad range of diseases such as cancer, diabetes, atherosclerosis, cataract and acute and chronic neurological disorders. Inflammation, the response of the host toward any infection or injury, plays a central role in the development of many chronic diseases. Several evidences demonstrated the rise of different types of cancer from sites of inflammation. This suggests that active oxygen species and some cytokines generated in the inflamed tissues can cause injury to DNA and ultimately lead to carcinogenesis. Diethylnitrosamine (DEN) is one of the most important environmental carcinogens, present in a variety of foods, alcoholic beverages, tobacco smoke and it can be synthesized endogenously. In addition to the liver it can induce carcinogenesis in other organs like kidney, trachea, lung, esophagus, fore stomach, and nasal cavity. Several epidemiological and laboratory studies indicate that nitroso compounds including DEN may induce hyperplasia and chronic inflammation which is closely associated with the development of hepatocellular carcinoma. Despite increasing evidence on the potential of antioxidants in modulating the etiology of chronic diseases, little is known about their role in inflammation and acute phase response (APR). Therefore the aim of the present work was to study the protective effect of water and solvent extracts of eight plant and plant byproducts including green tea, artichoke, spinach, broccoli, onion and eggplant, orange and potato peels as well as eight antioxidants agents including EC, EGC, ECG, EGCG, ascorbic acid (AA), acetylcysteine (NAC), α-LA, and alpha-tocopherol (α-TOC) toward acute inflammation induced by interleukin-6 (IL-6) and hepatotoxicity induced by DEN in vitro. The negative acute phase proteins (APP), transthyretin (TTR) and retinol-binding protein (RBP) were used as inflammatory biomarkers analyzed by ELISA, whereas neutral red assay was used for evaluating the cytotoxicity. All experiments were performed in vitro using human hepatocarcinoma cell line (HepG2). Additionally the antioxidant activity was measured by TEAC and FRAP assays, phenolic content was measured by Folin–Ciocalteu and characterized by HPLC. Moreover, the microheterogeneity of TTR was detected using immunoprecipitation assay combined with SELDI-TOF MS. Results of present study showed that HepG2 cells provide a simple, sensitive in vitro system for studying the regulation of the negative APP, TTR and RBP under free and inflammatory condition. IL-6, a potent proinflammatory cytokine, in a concentration of 25 ng/ml was able to reduce TTR and RBP secretion by approximately 50-60% after 24h of incubation. With exception of broccoli and water extract of onion which showed pro-inflammatory effects in this study, all other plant extracts, at specific concentrations, were able to elevate TTR secretion in normal condition and even under treatment of IL-6 where the effect was quite lower. Green tea followed by artichoke and potato peel exhibited the highest elevation in TTR concentration which reached 1.1 and 2.5 folds of control in presence and absences of IL-6 respectively. In general Plant extracts were ordered according their anti-inflammatory potency as following: in water extracts; green tea > artichoke > potato peel > orange peel > spinach > eggplant peel, where in solvent extracts; green tea > artichoke > potato peel > spinach > eggplant peel > onion > orange peel. The antiinflammatory effect of water extracts of green tea, artichoke and orange peel were significantly higher than their corresponding solvent extracts whereas water extracts of eggplant-, potato peels and spinach showed lower effect than their solvent extracts. On the other hand α-LA followed by EGCG and ECG exhibited the highest elevation in TTR concentration compared to other antioxidants. The relation between the anti-inflammatory potential and antioxidants activity and phenolic content for the investigated substances was generally weak. This may suggest the involvement of other mechanisms than antioxidants properties for the observed effect. TTR secreted by HepG2 cells has a molecular structure quite similar to the purified standard and serum TTR in which all the three main variants are contained including native, S-cystinylated and Sglutathionylated TTR. Interestingly, a variant with molecular mass of 13453.8 + 8.3 Da has been detected only in TTR secreted by HepG2. Among all investigated antioxidants and plant extracts, six substances were able to elevate the native preferable TTR variant. The potency of these substances can be ordered as following α-LA > NAC > onion > AA > EGCG > green tea. A weak correlation between elevation on TTR and shifting to the native form was observed. Similar weak correlation has also been observed between antioxidants activity and elevation in native TTR. Although DEN was able to induce cell death in a concentration dependent manner, it requires considerably higher concentrations for its effects especially after 24h. This may be attributed to a lack in cytochrome P450 enzymes produced by HepG2. At selected concentrations some antioxidants and plant extracts significantly attenuate DEN cytotoxicity as following: spinach > α-LA > artichoke > orange peel > eggplant peel > α-TOC > onion > AA. Contrary all other substances especially green tea, broccoli, potato peel, and ECG stimulate DEN toxicity. In conclusion, this study demonstrated that selected antioxidants and plant extracts may attenuate the inflammatory process, not only by their antioxidants potency but also by other mechanisms which remain unclear. They may also play a vital role on stabilizing the tetramic structure of TTR and thereby prevent amyloidosis diseases. Lipoic acid represents in this study unique function against inflammation and hepatotoxicity. Despite the protective effect demonstrated by investigated substances, attention should also be given to the pro-oxidant and potential cytotoxic effects produced at higher concentrations. / Substanzen und Lebensmittelinhaltstoffe mit antioxidativer Wirkung spielen eine entscheidende Rolle in Prävention und Behandlung zahlreicher Erkrankungen, die mit oxidativen Stress assoziiert sind. Dabei stehen v. a. die Lebensmittelinhaltsstoffen Vitamin C (Ascorbinsäure, AA), Vitamin E und die Carotinoide im Zentrum der Forschung. Da einige bislang relativ ungebräuchliche Antioxidantien wie Liponsäure (LA) und phenolische Substanzen wie (-)-Epicatechin (EC), (-)-Epigallocatechin(EGC), (-)-Epicatechingallat (ECG), und (-)-Epigallocatechingallat (EGCG) ein größeres antioxidatives Potential als Carotinoide und die Vitamine C und E aufweisen, geraten diese in zunehmendem Maße in den Fokus der Forschung und wecken auch immer mehr das Interesse gesundheitsbewusster Verbraucher. Einige ausgewählte Pflanzenextrakte und Extrake pflanzlicher Nebenprodukte stellen ergiebige Quellen der oben erwähnten Substanzen dar und zeichnen sich daher durch eine höhere Wirksamkeit aus, die teilweise auch auf synergetische Effekte zwischen diesen Antioxidantien zurückzuführen ist. Eine Vielzahl epidemiologischer Studien sowie zahlreiche Tier- und in-vitro-Experimente deuten daher darauf hin, daß die oben erwähnten Antioxidantien bei einer Vielzahl von Erkrankugen, wie Krebs, Diabetes, Arteriosklerose, Katarakt, akute bzw. chronische neurologische Störungen, ein schützendes und therapeutisches Potential entfalten. Entzündungen, als Antwort eines Individuums auf Infektion oder Verletzungen, spielen eine zentrale Rolle bei der Entwicklung vieler chronischer Erkrankungen. So konnten mehrere Studien den Zusammenhang zwischen der Entstehung verschiedener Krebsarten und zugrundeliegender Infektionen belegen. Dies deutet darauf hin, dass reaktive Sauerstoffspezies und einige Zytokinen, die im entzündeten Geweben generiert werden und DNA-Schäden verursachen können, letztendlich auch eine Karzinogenese auslösen können. Diethylnitrosamin (DEN) ist eines der bekanntesten Umweltkarzinogene, daß neben Hepatokarzinomen auch Krebs in Nieren, Trachea, Lunge, Speiseröhre, Magen und Nasenhöhle hervorrufen kann und in vielen Lebensmitteln, alkoholischen Getränke sowie Tabakrauch enthalten ist und darüber hinaus endogen synthetisiert wird. Dabei geht man auf Grundlage mehrere epidemiologischer und Forschungsstudien davon aus, dass durch Nitroso-Verbindungen, u.a. auch DEN, induzierte Hyperplasien und chronische Entzündungen die Entwicklung hepatozellulärer Karzinome begünstigt. Trotz zunehmender Beweise bezüglich des Potentials von Antioxidantien die Ätiologie chronischer Erkrankungen zu modulieren, ist bislang nur sehr wenig über ihre Rolle im Entzündungsprozess und der Akutphasereaktion (APR) bekannt. Deshalb war das Ziel der vorliegenden Arbeit die schützende Wirkung von Extrakten verschiedener Pflanzen und Pflanzennebenprodukten sowie isolierten Antikoxidantien bei akuten Entzündungssituationen zu testen. Dazu wurden wässrige und Lösungsmittelextratke aus acht Pflanzen bzw. deren Nebenprodukten (Grüntee, Artischocke, Spinat, Brokkoli, Zwiebel, Aubergine-, Orangen- und Kartoffelschalen) hergestellt und ihre Wirkung sowie die acht weiterer reiner Antioxidantien (EC, EGC, ECG, EGCG, Ascorbinsäure (AA), Acetylcystein (NAC), LA, und -Tocopherol (TOC) in in-vitro-Modellen der akuten Entzündung, induziert durch interleukin-6 (IL-6), bzw. der Hepatoxizität, induziert durch DEN, getestet.. Transthyretin (TTR) und Retinol-Bindungsprotein (RBP), zwei negative Akutphasenproteine (APP) wurden als Entzündungsbiomarker (Analyse per ELISA) und Neutral-Red-Assay als ein Maß für die Cytotoxizität herangezogen. Alle Experimente wurden in-vitro in einer immortalisierten humanen Hepatokarzinom-Zelllinie (HepG2) durchgeführt. Die antioxidativen Kapazität wurde mittels TEAC und FRAP-Methoden evaluiert und der Gesamtphenolgehalt durch die Folin–Ciocalteu-Methode erfasst, wobei die qualitative Charakterisierung über die HPLC erfolgte. Die Mikroheterogenität des TTR wurde durch Immunopräzipitation in Kombination mit SELDI-TOF-MS Technik analysiert. Die Ergebnisse dieser Studie zeigen, dass HepG2-Zellen ein einfaches und empfindliches in-vitro System zur Regulierung von negativen Akutphasenproteinen, TTR und RBP, unter physiologischen und infllammatorischen Bedingungen darstellen. IL-6, ein potentes Pro-Entzündungszytokine, war bei einer 24stündigen Inkubation mit einer Konzentration von 25 ng/ ml in der Lage die Sekretion von TTR und RBP um ca. 50-60% zu reduzieren. Mit Ausnahme von Broccoli und Wasser Extrakt der Zwiebel, die zeigten, proinflammatorischen Effekt Wirkungen in dieser Studie, die alle anderen Pflanzenextrakten, in bestimmten Konzentrationen, waren in der Lage zu erheben TTR Sekretion im normalen, aber auch bei der Behandlung von IL-6 bei denen die Wirkung war niedriger. Grüntee, gefolgt von Artischocken und Kartoffelschälen zeigte die höchste Erhebung in der TTRKonzentration, die erreicht, 1,1 und 2,5 Falten der Kontrolle in Behandlung und ohne Behandlung von IL-6 bzw. Die wässrigen Pflanzenextrakte lassen sich in der folgenden Reihenfolge des anti-Entzündungspotentials einordnen: Grüntee > Artischocke > Kartoffelschalen > Orangenschalen > Spinat > Aubergineschalen, wogegen bei Lösungsmittelextrakte folgende Reihenfolge ermittelt wurde: Grüntee > Artischocke > Kartoffelnschalen > Spinat > Aubergineschalen > Zwiebel > Orangenschalen. Die schützende Wirkung der wässrigen Extrakte von Grüntee, Artischocke und Orangenschalen war signifikant höher als die der entsprechenden Lösungsmittelextrakte. Wohingegen wässrige Extrakte aus Aubergineschalen, Kartoffelschalen, Spinat und Zwiebel weniger effektiv waren. Auf der anderen Seite, LA gefolgt von EGCG und ECG zeigte die höchste Erhebung in der TTRKonzentration im Vergleich zu anderen Antioxidantien. Somit konnte ein schwacher aber Zusammenhang zwischen antinflammatorischem Potential, antioxidativer Aktivität und Phenolgehalt nachgewiesen werden. Daher ist anzunehmen, dass den beobachteten Effekten anderen Mechanismen zu Grunde liegen. Das durch HepG2-Zellen sezernierte TTR erwies eine molekulare Struktur ähnlich der des verwendeten Standards bzw. des TTR aus humanem Serum auf. Es enthielt alle drei Hauptvarianten, einschließlich der nativen, S-cystinylierten und S-glutathionylierten TTR-Formen. Darüber hinaus wurde nur im in-vitro sezerniertem TTR (TTR aus HepG2-Zellen) eine Variante mit einer molekularen Masse von 13453.8 + 8.3 Da nachgewiesen. Von den untersuchten Substanzen wiesen nur sechs Verbindungen die Fähigkeit auf den Anteil der günstigen nativen TTR-Form zu erhöhen aus. Dabei konnte folgende Wirksamkeitsreihenfolge zugeordnet werden : LA > NAC > Zwiebel > AA > EGCG > Grüntee. Eine schwache Korrelation zwischen der Erhöhung der TTRKonzentration und der Verschiebung zu der nativen Form hin wurde festgestellt. Ein ähnlicher Zusammenhang zwischen der antioxidativen Aktivität und dieser Erhöhung wurde auch beobachtet. Obwohl DEN in der Lage war konzentrationsabhängig den Zelltod zu induzieren, war eine wesentlich höhere Konzentration notwendig, um die volle Wirksamkeit während 24stündiger Inkubation zu gewährleisten. Dies mag auf die mangelnde Ausstattung mit Cytochrom-P450-Enzymen, die in den HepG2 Zellen produziert werden, zurück zu führen sein. Ausgewählte Konzentrationen einiger eingesetzter Substanzen führten zu einer signifikanten Schwächung der DEN-induzierten Zytotoxizität mit folgender Wirksamkeit: Spinat > LA > Artischocke > Orangen- > Aubergineschalen > TOC > Zwiebel > AA. Im Gegensatz dazu, stimulierten alle anderen Substanzen, insbesondere Grüntee, Brokkoli, Kartoffelschalen und ECG, die DEN –induzierten Toxizität. Diese Arbeit zeigt somit, dass ausgewählte Antioxidantien und Pflanzenextrakten in der Lage sind, den antinflammatorischen Prozess sowohl durch ihre antioxidative Wirkung als auch durch bislang nicht aufgeklärten Mechanismen grundlegend zu beeinflussen. Sie könnten daher eine entscheidende Rolle bei der Stabilisierung von Proteinstrukturen übernehmen (gezeigt am Beispiel vom TTR) und in diesem Zusammenhang möglicherweise auch zur Prävention von Krankheiten wie Amyloidosen beitragen. Liponsäure überzeugte in dieser Arbeit durch seine einzigartigen Funktion gegenüber Entzündungssituationen und Hepatoxizität. Wie oft beobachtet und durch diese Studie bestätigt, weisen die verwendeten Subsatzen neben der schützenden anti- auch pro-oxidativen Wirkungen auf, wodurch die Notwendigkeit weiterer Untersuchungen zur Erfassung der Zytotoxizität beim Einsatz höherer Konzentration verdeutlicht wird.
4

DIETARY ANTIOXIDANT SUPPLEMENTATION (ECONOMASE–BIOPLEX) TO ALLEVIATE ADVERSE IMPACTS OF OXIDIZED OIL ON BROILER MEAT QUALITY: A CHEMICAL, TEXTURAL, ENZYMATIC, AND PROTEOMIC STUDY

Delles, Rebecca 01 January 2013 (has links)
This study investigated the influence of dietary antioxidants and quality of oil on the oxidative and enzymatic properties of chicken broiler meat stored in an oxygen-enriched package (HiOx: 80% O2/20% CO2) in comparison with air-permeable polyvinylchloride (PVC) or skin (SK) packaging systems during retail display 2–4 °C for up to 14, 7, and 21 d, respectively. Broilers were fed a diet either with a low-oxidized oil (peroxide vale POV 23 meq O2/kg) or with a high-oxidized oil (POV 121 meq O2/kg), supplemented with an antioxidant pack (200 ppm EconomasE and organic minerals Se, Zn, Cu, Mn, and Fe as in Bioplex) in substitution for vitamin E and inorganic minerals for 42 d. In all packaging systems, lipid oxidation and protein oxidation were inhibited by up to 65% with an antioxidant-supplemented diet when compared to diets without antioxidant supplements. Antioxidant enzyme activities were significantly higher (P < 0.05) in the antioxidant-supplemented diets compared with control diets, regardless of oil quality. Meat samples from the antioxidant-supplemented group, irrespective of oil quality, has less purge and cooking loss compared to control diets. In all packaging systems, meat shear force was higher (P < 0.05) for broilers fed high-oxidized diets than the low-oxidized groups. Comparison between muscle types (breast as white vs. thigh as red) showed a similar trend in muscle susceptibility to oxidized oil in the diet but greater protection of antioxidant supplements for thigh meat in both physiochemical and textural properties. Dietary regimen influenced protein expression in broiler breast meat. Three protein spots from 2-dimensional gel electrophoresis, identified by mass spectrometry as glyceraldehyde 3-phosphate dehydrogenase, creatine kinase, and heat shock protein beta-1 were over-abundant in muscle from low-oxidized diets. The differential proteomes that suggested down regulation of the genes encoding antioxidative proteins upon feeding oxidized oil may be implicated in the broiler meat quality deterioration during storage. In summary, feeding diets with poor oil quality increased the vulnerability of lipids and proteins to oxidation in broiler breast and thigh meat during refrigerated and / or frozen storage in various packaging conditions, yet these effects were alleviated upon dietary supplementation with antioxidants.
5

Suplementação de selênio e vitamina e em dietas para o pacu (Piaractus mesopotamicus) / Selenium and vitamin e supplementation in diets for pacu (Piaractus mesopotamicus)

Reis, Elenice Souza dos 24 February 2012 (has links)
Made available in DSpace on 2017-07-10T17:48:30Z (GMT). No. of bitstreams: 1 Elenice_Souza_dos Reis_Goes.pdf: 1132367 bytes, checksum: ad46353b729ffbe8f8a9758ac34166ed (MD5) Previous issue date: 2012-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This study aimed to evaluate the effect of levels of selenium and vitamin E on the productive performance, body earning and lipid stability of pacu. Were used 720 juvenile pacu (initial weight 43,52±1,03g), distributed in a completely randomized design with 36 cages of 1m³ each, installed in a masonry tank with 200m². For 100 days, the animals were fed until apparent satiation, twice a day, with based diet containing 26% of crude protein and 3000 Kcal of disgestible energy/kg. Each diet was supplemented with 4 levels of selenium (0, 1, 2 and 4 mg/kg of ration) combined with 3 levels of vitamin E (0, 100 and 200 mg/kg of ration), in a factorial scheme of 4x3, totaling twelve treatments, with three repetitions for each level. At the end of the experimental period, the fish fasted for 24 hours, and then performed the procedures for analysis of productive performance (total and standart lengths, weight gain, feed conversion ratio and survival) and of body earning (carcass, clean torso, head, visceral fat and hepatosomatic index). The clean torsos were stored under freezing for analysis of centesimal composition (humidity, protein, lipid and ash), and on days 60, 90 e 120 was performed analysis of lipid oxidation by thiobarbituric acid reactive substances. The levels of selenium (0, 1, 2 and 4 mg/kg of ration) combined with vitamin E levels (0, 100 and 200 mg/kg of ration) did not influence (p>0,05) on productive performance, body earning, physical and chemical composition of juvenile pacu (P. mesopotamicus). These parameters varied in accordance with the findings of other authors for the species. The interaction between levels of selenium and vitamin E did not influence (p>0,05) the lipid stability of clean torsos of pacu; however, evaluating only levels of vitamin E, the level of 200 mg vitamin E/kg of ration decreases the lipid oxidation in 90 and 120 days of storage. Just the level 0 Se + 0 vitamin E/kg of ration was influenced by storage time, and the highest rate of lipid oxidation was verified with 120 days of storage. The conclusion is that the level of 1 mg selenium + 200 mg vitamin E/kg of ration keeps the performance, body earnings and centesimal composition of juvenile pacu (P. mesopotamicus), besides reducing the lipid oxidation after 90 days of under freezing storage / Este estudo teve por objetivo avaliar a suplementação de selênio e vitamina E na dieta sobre o desempenho produtivo, rendimentos corporais, composição centesimal e estabilidade lipídica do pacu. Foram utilizados 720 juvenis de pacu (peso inicial 43,52±1,03g), distribuídos em 36 tanques-rede de 1m³ cada, instalados ao acaso em um tanque de alvenaria com 200m². Durante 100 dias, os animais foram alimentados até a saciedade aparente, duas vezes ao dia, com dietas base contendo 26% de proteína bruta e 3000 Kcal de energia digestível/kg. Cada dieta foi suplementada com 4 níveis de selênio (0, 1, 2 e 4 mg/kg de ração) combinados com 3 níveis de vitamina E (0, 100 e 200 mg/kg de ração), em um esquema fatorial 4x3, totalizando assim doze tratamentos, com três repetições para cada nível. Ao final do experimento, os peixes permaneceram em jejum por 24 horas, sendo insensibilizados em benzocaína e feitas as análises de desempenho produtivo (comprimentos total e padrão, ganho de peso, conversão alimentar aparente e sobrevivência) e dos rendimentos corporais (carcaça, tronco limpo, cabeça, gordura visceral e índice hepatossomático). Os troncos limpos foram armazenados sob congelamento para análise da composição centesimal (umidade, proteína, lipídeos e cinzas), e nos dias 60, 90 e 120 foi realizada análise de oxidação lipídica através das substâncias reativas ao ácido tiobarbitúrico. Os níveis de selênio (0, 1, 2 e 4 mg/kg de ração) combinados com níveis de vitamina E (0, 100 e 200 mg/kg de ração) não influenciaram (p>0,05) no desempenho produtivo, rendimentos corporais e composição centesimal de juvenis de pacu (P. mesopotamicus). Estes parâmetros variaram de acordo com os encontrados por outros autores para a espécie. A interação entre níveis de selênio e vitamina E não influenciou (p>0,05) na estabilidade lipídica de troncos limpos de pacu; porém avaliando apenas os níveis de vitamina E, o nível de 200 mg de vitamina E/kg de ração diminui a oxidação lipídica em 90 e 120 dias de estocagem. Somente o nível 0 Se + 0 vitamina E/kg de ração foi influenciado pelo tempo de estocagem, sendo que a maior taxa de oxidação lipídica foi verificada com 120 dias de estocagem. Conclui-se que o nível 1 mg selênio + 200 mg vitamina E/kg de ração mantém o desempenho, rendimentos corporais e composição centesimal de juvenis de pacus (P. mesopotamicus), além de diminuir a oxidação lipídica após 90 dias de estocagem sob congelamento
6

The relationship among serum levels of manganese superoxide dismutase and mtDNA 8-hydroxy-2'-deoxyguanosine, and dietary antioxidants intake in Type 2 Diabetes

MCLEAN, MICHAEL ANDREW 03 October 2014 (has links)
Oxidative stress plays a key role in the development of Type 2 Diabetes (T2D). This cross-sectional study examined the relationship among serum levels of manganese superoxide dismutase (MnSOD), 8-hydroxy-2’-deoxyguanosine (8OHdG), dietary antioxidant intakes and glycemic control in African Americans (n=209) and Haitian Americans (n=234) with and without T2D. African Americans had higher BMI (32.8 vs. 29.3 kg/m2), higher energy intake (2148 vs. 1770 kcal), and were more educated as compared to Haitian Americans; all variables were significant at p < .001. Serum levels of 8OHdG and MnSOD for African Americans (1691.0 ± 225.1 pg/ml, 2538.0 ± 1091.8 pg/ml; respectively) were significantly higher than for Haitian Americans (1626.2 ± 222.9, 2015.8 ± 656.3 pg/ml; respectively). 8OHdG was negatively correlated with MnSOD (r = -.167, p < .001) in T2D. Having T2D was negatively correlated with MnSOD (r = -.337; p < .01) and positively correlated with 8OHdG (r = .500; p < .01). African Americans and Haitian Americans with T2D had fasting plasma glucose (FPG) levels of 143.0 ± 61.0 mg/dl and 157.6 ± 65.5 mg/dl, and A1C of 7.5 ± 1.8 % and 8.4 ± 2.4 %, respectively. African Americans and Haitian Americans without T2D had FPG levels of 95.8 ± 13.2 mg/dl and 98.7 ± 16.9 mg/dl, and A1C of 5.9 ± 0.4% and 6.0 ± 0.5%, respectively. Dietary intakes of vitamin C and vitamin D were negatively correlated with FPG (r = -.21; r = -.19, p < .05) respectively. Carotenoids negatively correlated with A1C (r = -.19, p < .05). Lower levels of MnSOD were associated with lower levels of zinc, r = .10, p < .05, and higher levels of carotenoids r = -.10, p < .05. Higher levels of 8OHdG were associated with lower levels of Vitamin D, r = -.14, p < .01, and carotenoids, r = -.09, p < .05. The results demonstrate greater oxidative mtDNA damage in persons with T2D compared to those without T2D and in African Americans compared with Haitian Americans. The inverse relationship between dietary intake of antioxidants and oxidative stress implies a potential to reduce oxidative stress with diet. African Americans were significantly younger (53.3 vs. 55.6 years), had higher BMI (32.8 vs. 29.3 kg/m2), higher energy intake (2148 vs. 1770 kcal), and were more educated as compared to Haitian Americans; all variables were significant at p < .001. Serum levels of 8OHdG and MnSOD for African Americans (1691.0 ± 225.1 pg/ml, 2538.0 ± 1091.8 pg/ml; respectively) were significantly higher than for Haitian Americans (1626.2 ± 222.9, 2015.8 ± 656.3 pg/ml; respectively). 8OHdG was negatively correlated with MnSOD (r = -.167, p < .001) in T2D. Having T2D was negatively correlated with MnSOD (r = -.337; p < .01) and positively correlated with 8OHdG (r = .500; p < .01). African Americans and Haitian Americans with T2D had fasting plasma glucose (FPG) levels of 143.0 ± 61.0 mg/dl and 157.6 ± 65.5 mg/dl, and A1C of 7.5 ± 1.8 % and 8.4 ± 2.4 %, respectively. African Americans and Haitian Americans without T2D had FPG levels of 95.8 ± 13.2 mg/dl and 98.7 ± 16.9 mg/dl, and A1C of 5.9 ± 0.4% and 6.0 ± 0.5%, respectively. Dietary intakes of vitamin C and vitamin D were negatively correlated with FPG (r = -.21; r = -.19, p < .05) respectively. Carotenoids negatively correlated with A1C (r = -.19, p < .05). Lower levels of MnSOD were associated with lower levels of zinc, r = .10, p < .05, and higher levels of carotenoids r = -.10, p < .05. Higher levels of 8OHdG were associated with lower levels of Vitamin D, r = -.14, p < .01, and carotenoids, r = -.09, p < .05. The results demonstrate greater oxidative mtDNA damage in persons with T2D compared to those without T2D and in African Americans compared with Haitian Americans. The inverse relationship between dietary intake of antioxidants and oxidative stress implies a potential to reduce oxidative stress with diet.

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