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Eicosapentaenoic acid free fatty acid prevents and suppresses colonic neoplasia in colitis-associated colorectal cancer acting on Notch signaling and gut microbiotaPiazzi, G., D'Argenio, G., Prossomariti, A., Lembo, V., Mazzone, G., Candela, M., Biagi, E., Brigidi, P., Vitaglione, P., Fogliano, V., D'Angelo, L., Fazio, C., Munarini, A., Belluzzi, A., Ceccarelli, C., Chieco, P., Balbi, T., Loadman, Paul, Hull, M.A., Romano, M., Bazzoli, F., Ricciardiello, L. 28 March 2014 (has links)
No / Inflammatory bowel diseases are associated with increased risk of developing colitis-associated colorectal cancer (CAC). Epidemiological data show that the consumption of ω-3 polyunsaturated fatty acids (ω-3 PUFAs) decreases the risk of sporadic colorectal cancer (CRC). Importantly, recent data have shown that eicosapentaenoic acid-free fatty acid (EPA-FFA) reduces polyp formation and growth in models of familial adenomatous polyposis. However, the effects of dietary EPA-FFA are unknown in CAC. We tested the effectiveness of substituting EPA-FFA, for other dietary fats, in preventing inflammation and cancer in the AOM-DSS model of CAC. The AOM-DSS protocols were designed to evaluate the effect of EPA-FFA on both initiation and promotion of carcinogenesis. We found that EPA-FFA diet strongly decreased tumor multiplicity, incidence and maximum tumor size in the promotion and initiation arms. Moreover EPA–FFA, in particular in the initiation arm, led to reduced cell proliferation and nuclear β-catenin expression, whilst it increased apoptosis. In both arms, EPA-FFA treatment led to increased membrane switch from ω-6 to ω-3 PUFAs and a concomitant reduction in PGE2 production. We observed no significant changes in intestinal inflammation between EPA-FFA treated arms and AOM-DSS controls. Importantly, we found that EPA-FFA treatment restored the loss of Notch signaling found in the AOM-DSS control and resulted in the enrichment of Lactobacillus species in the gut microbiota. Taken together, our data suggest that EPA-FFA is an excellent candidate for CRC chemoprevention in CAC.
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Eicosapentaenoic acid and aspirin, alone and in combination, for the prevention of colorectal adenomas (seAFOod Polyp Prevention trial): a multicentre, randomised, double-blind, placebo-controlled, 2 × 2 factorial trialHull, M.A., Sprange, K., Hepburn, T., Tan, W., Shafayat, A., Rees, C.J., Clifford, G., Logan, R.F., Loadman, Paul, Williams, E.A., Whitham, D., Montgomery, A.A. 19 November 2018 (has links)
Yes / Background: The omega-3 polyunsaturated fatty acid eicosapentaenoic acid (EPA) and aspirin both have proof of
concept for colorectal cancer chemoprevention, aligned with an excellent safety profile. Therefore, we aimed to test
the efficacy of EPA and aspirin, alone and in combination and compared with a placebo, in individuals with sporadic
colorectal neoplasia detected at colonoscopy.
Methods: In a multicentre, randomised, double-blind, placebo-controlled, 2 × 2 factorial trial, patients aged 55–73 years
who were identified during colonoscopy as being at high risk in the English Bowel Cancer Screening Programme
(BCSP; ≥3 adenomas if at least one was ≥10 mm in diameter or ≥5 adenomas if these were <10 mm in diameter) were
recruited from 53 BCSP endoscopy units in England, UK. Patients were randomly allocated (1:1:1:1) using a secure
web-based server to receive 2 g EPA-free fatty acid (FFA) per day (either as the FFA or triglyceride), 300 mg aspirin per
day, both treatments in combination, or placebo for 12 months using random permuted blocks of randomly varying
size, and stratified by BCSP site. Research staff and participants were masked to group assignment. The primary
endpoint was the adenoma detection rate (ADR; the proportion of participants with any adenoma) at 1 year surveillance
colonoscopy analysed in all participants with observable follow-up data using a so-called at-the-margins approach,
adjusted for BCSP site and repeat endoscopy at baseline. The safety population included all participants who received
at least one dose of study drug. The trial is registered with the International Standard Randomised Controlled Trials
Number registry, number ISRCTN05926847.
Findings: Between Nov 11, 2011, and June 10, 2016, 709 participants were randomly assigned to four treatment groups
(176 to placebo, 179 to EPA, 177 to aspirin, and 177 to EPA plus aspirin). Adenoma outcome data were available for
163 (93%) patients in the placebo group, 153 (85%) in the EPA group, 163 (92%) in the aspirin group, and 161 (91%) in
the EPA plus aspirin group. The ADR was 61% (100 of 163) in the placebo group, 63% (97 of 153) in the EPA group,
61% (100 of 163) in the aspirin group, and 61% (98 of 161) in the EPA plus aspirin group, with no evidence of any
effect for EPA (risk ratio [RR] 0·98, 95% CI 0·87 to 1·12; risk difference –0·9%, –8·8 to 6·9; p=0·81) or aspirin
(RR 0·99 (0·87 to 1·12; risk difference –0·6%, –8·5 to 7·2; p=0·88). EPA and aspirin were well tolerated (78 [44%] of
176 had ≥1 adverse event in the placebo group compared with 82 [46%] in the EPA group, 68 [39%] in the aspirin
group, and 76 [45%] in the EPA plus aspirin group), although the number of gastrointestinal adverse events was
increased in the EPA alone group at 146 events (compared with 85 in the placebo group, 86 in the aspirin group, and
68 in the aspirin plus placebo group). Six upper-gastrointestinal bleeding events were reported across the treatment
groups (two in the EPA group, three in the aspirin group, and one in the placebo group).
Interpretation Neither EPA nor aspirin treatment were associated with a reduction in the proportion of patients with
at least one colorectal adenoma. Further research is needed regarding the effect on colorectal adenoma number
according to adenoma type and location. Optimal use of EPA and aspirin might need a precision medicine approach
to adenoma recurrence. / Efficacy and Mechanism Evaluation Programme, a UK Medical Research Council and National Institute for Health Research partnership. / Research Development Fund Publication Prize Award winner, November 2018.
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Luminal Bioavailability of Orally Administered ω-3 PUFAs in the Distal Small Intestine, and Associated Changes to the Ileal Microbiome, in Humans with a Temporary IleostomyNana, G., Mitra, S., Watson, H., Young, C., Wood, H.M., Perry, S.L., Race, Amanda D., Quirke, P., Toogood, G.J., Loadman, Paul, Hull, M.A. 06 July 2021 (has links)
Yes / Background: Oral administration of purified omega-3 (ω-3) PUFAs is associated with changes to the fecal microbiome. However, it is not known whether this effect is associated with increased PUFA concentrations in the gut.
Objectives: We investigated the luminal bioavailability of oral ω-3 PUFAs (daily dose 1 g EPA and 1g DHA free fatty acid equivalents as triglycerides in soft-gel capsules, twice daily) and changes to the gut microbiome, in the ileum.
Methods: Ileostomy fluid (IF) and blood were obtained at baseline, after first capsule dosing (median 2 h), and at a similar time after final dosing on day 28, in 11 individuals (median age 63 y) with a temporary ileostomy. Fatty acids were measured by LC–tandem MS. The ileal microbiome was characterized by 16S rRNA PCR and Illumina sequencing.
Results: There was a mean 6.0 ± 9.8-fold and 6.6 ± 9.6-fold increase in ileal EPA and DHA concentrations (primary outcome), respectively, at 28 d, which was associated with increased RBC ω-3 PUFA content (P ≤ 0.05). The first oral dose did not increase the ileal ω-3 PUFA concentration except in 4 individuals, who displayed high luminal EPA and DHA concentrations, which reduced to concentrations similar to the overall study population at day 28, suggesting physiological adaptation. Bacteroides, Clostridium, and Streptococcus were abundant bacterial genera in the ileum. Ileal microbiome variability over time and between individuals was large, with no consistent change associated with acute ω-3
PUFA dosing. However, high concentrations of EPA and DHA in IF on day 28 were associated with higher abundance of Bacteroides (r2 > 0.86, P < 0.05) and reduced abundance of other genera, including Actinomyces (r2 > 0.94, P < 0.05).
Conclusions: Oral administration of ω-3 PUFAs leads to increased luminal ω-3 PUFA concentrations and changes to the microbiome, in the ileum of individuals with a temporary ileostomy.
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Antibacterial free fatty acids from the marine diatom, Phaeodactylum tricornutumDesbois, Andrew P. January 2008 (has links)
The aim of this thesis was to isolate the compounds responsible for the antibacterial activity of cell extracts of the marine diatom, Phaeodactylum tricornutum. Marine microalgae are not only important primary producers but, due to their phylogenetic diversity, they are also a potential source of novel bioactive compounds. The marine diatom, P. tricornutum, was selected for study because its cell extracts are known to be antibacterial but the compounds responsible have not been isolated. In this thesis, the compounds responsible for the antibacterial activity are isolated from aqueous methanol P. tricornutum cell extracts by column chromatography and reverse phase high-performance liquid chromatography using a bioassay-guided approach. The compounds in three active fractions were identified by mass spectrometry and nuclear magnetic resonance spectroscopy as the unsaturated fatty acids (5Z, 8Z, 11Z, 14Z, 17Z)-eicosapentaenoic acid, (9Z)-hexadecenoic acid and (6Z, 9Z, 12Z)-hexadecatrienoic acid. The fatty acids were found to be antibacterial against Staphylococcus aureus at micromolar concentrations. P. tricornutum exists in different cell morphs and, interestingly, extracts prepared from cultures in the fusiform morph were found to have greater antibacterial activity than extracts from oval cultures. This is explained by greater levels of the three antibacterial fatty acids in the fusiform cell extracts. The antibacterial fatty acids are proposed to be released by enzyme action when the diatom cells lose their integrity. The release of free fatty acids by diatoms is suggested to be a simple, very low cost population-level activated defence mechanism against potential pathogenic bacteria triggered when the cell loses its integrity. Further, this pathway may act against multiple threats to the microalga, including grazers, as fatty acids exhibit activity in diverse biological assays. Finally, whilst two of the fatty acids, (9Z)-hexadecenoic acid and (5Z, 8Z, 11Z, 14Z, 17Z)-eicosapentaenoic acid, inhibited the growth of MRSA their usefulness as therapeutic compounds may be limited due to their instability and their broad biological activity.
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The role of omega-3 fatty acids in the treatment of schizophrenia through modification of membrane phospholipidsAreda, Martha January 2016 (has links)
Ever since the emergence of the hypothesis that linked the aetiology of schizophrenia with abnormal membrane phospholipids composition, an increasing number of evidences have suggested reduced membrane polyunsaturated fatty acids in patients with schizophrenia. This has led to a conduct of several studies to evaluate the efficacy of omega-3 fatty acid supplement in the modification of membrane phospholipids and treatment of schizophrenia. The two main omega-3 fatty acid classes, EPA and DHA, play a vital role in membranes. This project work reviews omega-3 fatty acid studies and summarizes their outcomes. Eight original articles (nine studies) were reviewed. Six out of nine studies measured RBC membrane fatty acids levels and all six studies reported a significant increase in EPA after EPA supplement. Two studies reported increased DHA post omega-3 fatty acid and DHA supplement, respectively. One study observed a dose-dependent increment in DHA after EPA supplement. Improved symptoms were observed in seven studies, while one study found a worsening of symptoms in patients with low baseline PUFA. Moreover, out of the six studies that evaluated the correlation between symptom change and membrane fatty acids change, three studies observed a correlation between increased EPA and symptom improvement. One study reported an increased AA associated with improved symptoms, in contrast to another study, which found a correlation between increased AA and worsened symptoms. The conclusion from this project work is that EPA supplement can increase the EPA levels in membranes; however, its therapeutic effect in schizophrenia requires further investigation using larger studies. / Ända sedan tillkomsten av hypotesen som länkade etiologin av schizofreni med onormala sammansättningar av membranfosfolipider, har bevis för nedsatt membranfettsyror hos patienter med schizofreni ökat. Detta har lett till genomförandet av flera studier för att utvärdera effekten av omega-3 supplement i modifieringen av membranfosfolipider och i behandling av schizofreni. De två viktigaste omega-3 klasserna, EPA och DHA, spelar en viktig roll i membran. Detta projektarbete granskar de omega-3 studierna och sammanfattar deras resultat. Åtta originalartiklar (nio studier) granskades. Sex av nio studier mätte nivåer av RBC membranfettsyror och alla sex studierna rapporterade en signifikant ökning av EPA efter EPA behandling. Två studier rapporterade ökad DHA efter omega-3 och DHA behandling, respektive. En studie observerade en dosberoende ökning i DHA efter EPA behandling. Förbättrade symtom observerades i sju studier, medan en studie fann en försämring av symtom hos patienter med låg baseline PUFA. Av de sex studier som utvärderade sambandet mellan symtomförändring och förändring i membranfettsyror, hittade två studier samband mellan ökad EPA och symtomförbättring. En studie rapporterade en ökad AA i samband med förbättrade symtom, i motsats till en annan studie, som fann ett samband mellan ökad AA och försämrade symtom. Slutsatsen från detta projektarbete är att EPA tillägg ökar nivåer av EPA i membranfosfolipider; men dess terapeutiska effekt vid schizofreni kräver ytterligare utredning med hjälp av större studier.
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Omega-3 Fatty Acid Blood Biomarkers Before and After Acute Fish Oil Supplementation in Men and WomenMetherel, Adam Henry January 2007 (has links)
Omega-3 fatty acids, particularly docosahexaenoic (DHA) and eicospentaenoic acid (EPA), are important mediators for cardiovascular disease, fetal/infant development, neurological disorders and inflammatory diseases. Supplementation and washout studies are important for future research on the physiological effects of omega-3 fatty acids and for determination of the proper washout period for future cross-over studies. In this study, omega-3 fatty acid blood biomarker comparisons are made for the n-3 HUFA score (% of n-3 HUFAs in total HUFAs) and omega-3 index (sum of EPA + DHA) in plasma, erythrocytes, whole blood and a novel finger-tip prick blood method (FTPB) of analysis. This FTPB method of fatty acid analysis is further tested to determine the potential for its use in fatty acid analysis. In addition, gender differences in response to omega-3 fish oil supplementation are analyzed in all four blood fractions.
Nine males and seven females were supplemented with 8 fish-oil capsules per day (providing 3.2 g/day EPA and 1.6 g/day DHA) for four weeks, followed by an eight-week omega-3 washout period. Venous plasma, erythrocyte and whole blood samples were collected during weeks 0, 4, 8 and 12 and FTPB samples were collected weekly during supplementation and washout fatty acid analysis was performed.
EPA and DHA incorporation is lowest in magnitude in erythrocytes relative to all other blood fractions. Omega-3 blood biomarker comparisons demonstrate that the n-3 HUFA score is a more reliable measure across all blood fractions compared to the omega-3 index. In addition, the n-3 HUFA score demonstrates no differences (p > 0.05) between FTPB and whole blood analysis, providing evidence to support its usefulness as a tool for fatty acid analysis. However, differences (p < 0.05) do exist between these methods for saturated fatty acid, monounsaturated fatty acids, omega-6 polyunsaturated fatty acids (PUFAs) and omega-3 PUFAs. Baseline fatty acid levels for DHA, and the DHA:EPA and DHA:DPA ratios tend to be higher (p < 0.05) in females, and docosapentaenoic acid n-3 (DPAn-3) is higher (p > 0.05) in males across all blood fractions. Furthermore, a gender effect (p < 0.05) is seen for the DHA:EPA ratio across all blood fractions. At baseline, female DHA:EPA is higher (p < 0.05) than males with supplementation lowering both male and female values and removing any differences (p > 0.05) between genders. Washout results in a return of levels towards baseline, however, baseline levels are not fully reached. Furthermore, while gender differences do begin to reform during washout, these differences are not significant (p > 0.05).
In conclusion, omega-3 fatty acid responses, particularly DHA:EPA ratio, demonstrate significant gender differences that may be related to differences in long-chain PUFA synthesis pathways between males and females. In addition, the n-3 HUFA score may be a more valuable omega-3 blood biomarker than the omega-3 index, as the n-3 HUFA score displays more consistent levels across all blood fractions. Finally, the FTPB method of analysis may be a useful tool in the measurement of fatty acid composition, however, some microwave methylation problems do exist, specifically in the phospholipid class of lipids.
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Omega-3 Fatty Acid Blood Biomarkers Before and After Acute Fish Oil Supplementation in Men and WomenMetherel, Adam Henry January 2007 (has links)
Omega-3 fatty acids, particularly docosahexaenoic (DHA) and eicospentaenoic acid (EPA), are important mediators for cardiovascular disease, fetal/infant development, neurological disorders and inflammatory diseases. Supplementation and washout studies are important for future research on the physiological effects of omega-3 fatty acids and for determination of the proper washout period for future cross-over studies. In this study, omega-3 fatty acid blood biomarker comparisons are made for the n-3 HUFA score (% of n-3 HUFAs in total HUFAs) and omega-3 index (sum of EPA + DHA) in plasma, erythrocytes, whole blood and a novel finger-tip prick blood method (FTPB) of analysis. This FTPB method of fatty acid analysis is further tested to determine the potential for its use in fatty acid analysis. In addition, gender differences in response to omega-3 fish oil supplementation are analyzed in all four blood fractions.
Nine males and seven females were supplemented with 8 fish-oil capsules per day (providing 3.2 g/day EPA and 1.6 g/day DHA) for four weeks, followed by an eight-week omega-3 washout period. Venous plasma, erythrocyte and whole blood samples were collected during weeks 0, 4, 8 and 12 and FTPB samples were collected weekly during supplementation and washout fatty acid analysis was performed.
EPA and DHA incorporation is lowest in magnitude in erythrocytes relative to all other blood fractions. Omega-3 blood biomarker comparisons demonstrate that the n-3 HUFA score is a more reliable measure across all blood fractions compared to the omega-3 index. In addition, the n-3 HUFA score demonstrates no differences (p > 0.05) between FTPB and whole blood analysis, providing evidence to support its usefulness as a tool for fatty acid analysis. However, differences (p < 0.05) do exist between these methods for saturated fatty acid, monounsaturated fatty acids, omega-6 polyunsaturated fatty acids (PUFAs) and omega-3 PUFAs. Baseline fatty acid levels for DHA, and the DHA:EPA and DHA:DPA ratios tend to be higher (p < 0.05) in females, and docosapentaenoic acid n-3 (DPAn-3) is higher (p > 0.05) in males across all blood fractions. Furthermore, a gender effect (p < 0.05) is seen for the DHA:EPA ratio across all blood fractions. At baseline, female DHA:EPA is higher (p < 0.05) than males with supplementation lowering both male and female values and removing any differences (p > 0.05) between genders. Washout results in a return of levels towards baseline, however, baseline levels are not fully reached. Furthermore, while gender differences do begin to reform during washout, these differences are not significant (p > 0.05).
In conclusion, omega-3 fatty acid responses, particularly DHA:EPA ratio, demonstrate significant gender differences that may be related to differences in long-chain PUFA synthesis pathways between males and females. In addition, the n-3 HUFA score may be a more valuable omega-3 blood biomarker than the omega-3 index, as the n-3 HUFA score displays more consistent levels across all blood fractions. Finally, the FTPB method of analysis may be a useful tool in the measurement of fatty acid composition, however, some microwave methylation problems do exist, specifically in the phospholipid class of lipids.
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Populações de macrófagos em músculos esqueléticos de camundongos mdx tratados com ácido eicosapentaenóico / Population of macrophages in skeletal muscles of mdx mice treated with eicosapentaenoic acidDe Carvalho, Samara Camaçarí, 1982- 21 August 2018 (has links)
Orientadores: Maria Julia Marques, Selma Maria Michelin Matheus / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-21T06:49:40Z (GMT). No. of bitstreams: 1
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Previous issue date: 2012 / Resumo: A distrofia muscular de Duchenne (DMD) é uma miopatia progressiva causada pela ausência da proteína distrofina e necrose muscular progressiva. No camundongo mdx, modelo da DMD, a resposta inflamatória é exacerbada e populações distintas de macrófagos, M1 e M2, influenciam a degeneração e regeneração muscular, respectivamente, regulando a progressão da doença. Anti-inflamatórios esteróides são utilizados para a terapia farmacológica da DMD. Contudo, os efeitos colaterais decorrentes do seu uso contínuo estimulam o desenvolvimento de novas terapias farmacológicas para esta doença. No presente trabalho, verificamos os efeitos do ácido eicosapentaenóico (EPA) sobre os macrófagos M1 e M2 nos músculos bíceps braquial (BB), diafragma (DIA) e quadríceps femoral (QDR) do camundongo mdx. Camundongos mdx (14 dias de vida pós-natal) receberam 300mg/Kg de EPA diluído em óleo mineral, via gavagem, diariamente, por 16 dias. Camundongos mdx não tratados e camundongos C57BL/10 não tratados receberam óleo mineral via gavagem, pelo mesmo período. Verificamos que o EPA diminuiu a mionecrose (redução da CK no plasma) e aumentou o número de fibras com núcleo periférico, principalmente no BB e DIA. Em todos os músculos estudados, o tratamento com EPA diminuiu significativamente a área total de inflamação. Nos músculos BB e DIA, o tratamento com EPA aumentou a área de macrófagos M2. No QDR, observou-se predominância de regeneração muscular após o EPA, evidenciada por extensas áreas contendo fibras com núcleo central, em diferentes estágios de regeneração. Estes resultados sugerem que o EPA altera o balanço entre os macrófagos M1 e M2, promovendo diminuição de macrófagos M1, citotóxicos, o que pode contribuir para a proteção contra a mionecrose dos músculos distróficos / Abstract: Duchenne muscular dystrophy (DMD) is a progressive myopathy characterized by the absence of dystrophin and progressive muscle necrosis. In the mdx mice model of DMD, the inflammatory response is exacerbated and distinct macrophage populations, M1 and M2, influence muscle degeneration and regeneration, respectively, regulating the progression of the disease. Antiinflammatory steroids are the choice pharmacological therapy for DMD. However, their side effects stimulate the development of new drug therapies for this disease. In the present study, we observed the effects of eicosapentaenoic acid (EPA) on M1 and M2 macrophages in the biceps brachii (BB), diaphragm (DIA) and quadriceps (QDR) muscles of the mdx mice. Mdx mice (14 days old) received 300mg/kg of EPA diluted in mineral oil by gavage, daily, for 16 days. Untreated mdx and C57BL/10 mice received mineral oil by gavage for the same period. We observed that EPA decreased myonecrosis (reduced plasma CK) and increased the number of fibers with peripheral nuclei, mainly in the BB and DIA. In all muscles, treatment with EPA significantly decreased the total area of inflammation. In DIA and BB muscles, treatment with EPA increased the area of M2 macrophage. In the QDR, there was a predominance of muscle regeneration after EPA, with extensive areas containing fibers with central nuclei at different stages of regeneration. These results suggest that EPA affects the balance of M1 and M2 macrophages in dystrophic muscles, with a trend towards a decrease in the cytotoxic M1 phenotype, which may contribute to the protection against myonecrosis in the dystrophic muscles / Mestrado / Anatomia / Mestra em Biologia Celular e Estrutural
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Production of microcapsules containing fish oil omega-3 polyunsatureted fatty acid ethyl esters = Produção de microcápsulas contendo éster etílico de ácidos graxos polinsaturados ômega-3 de óleo de peixe / Produção de microcápsulas contendo éster etílico de ácidos graxos polinsaturados ômega-3 de óleo de peixeConto, Leilane Costa de, 1984- 21 August 2018 (has links)
Orientador: Lireny Aparecida Guaraldo Gonçalves / Texto em português e inglês / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-21T10:35:40Z (GMT). No. of bitstreams: 1
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Previous issue date: 2012 / Resumo: Óleos e gorduras são importantes na alimentação humana como fonte de energia,além de alguns serem considerados essenciais ao funcionamento dos organismos, tais como determinados ácidos graxos polinsaturados ômega-3. O ácido eicosapentaenóico (EPA) e o ácido docosahexaenóico (DHA), provenientes de fontes marinhas, são as principais formas de ingestão direta de ômega-3,porém estes são muito sensíveis à oxidação e apresentam flavors característicos que levam à rejeição por alguns consumidores. Uma alternativa para contornar estes problemas é a microencapsulação. Uma técnica muito difundida para este tipo de produto sensível é a coacervação, no entanto algumas novas técnicas vêm surgindo na busca de solução destas deficiências. A gelificação enzimática pode ser citada como uma nova tecnologia que objetiva reduzir algumas etapas do processo e tempo de produção, se comparado ao processo de coacervação.Neste trabalho buscou-se compreender o comportamento do material de recheio (éster etílico de óleo de peixe), visto que são encontrados poucos estudos referentes às análises da integridade dos materiais de recheio de natureza lipídica quando encapsulados, e dos materiais de parede (principalmente isolado protéico de soja e isolado protéico de soro) quando utilizados para a produção de microcápsulas por gelificação enzimática e por coacervação complexa, avaliando tanto as cargas eletrostáticas do meio pelo seu potencial zeta para a coacervação, quanto na caracterização completa das cápsulas produzidas por gelificação enzimática e coacervação. Entre os materiais de parede estudados, foram utilizados isolado protéico de soro e isolado protéico de soja, sendo que este último na concentração de 10% apresentou formação de microcápsulas com características superiores pela técnica de gelificação enzimática. Quando estudadas mais a fundo as características das microcápsulas produzidas por gelificação enzimática, a ánalise do material encapsulado constatou-se que ocorreu a encapsulação de óleo de milho da segunda emulsão, reduzindo assim a eficiência real de encapsulação, mostrando-se assim uma técnica não eficaz,mesmo se obtendo cápsulas com elevada resistência mecânica. Comparando-se os métodos de degradação destas cápsulas, foi observada a total degradação da parede para a metodologia de degradação ácida, e parcial para a metodologia de degradação enzimática alcalina. Entretanto a melhor metodologia de degradação para se determinar a composição do material encapsulado foi a degradação ácida com determinação direta da composição em ácidos graxos. No estudo estatístico de microcápsulas contendo éster etílico de óleo de peixe produzidas por coacervação complexa utilizando isolado protéico de soja e goma arábica como material de parede obteve-se cápsulas contendo mais de 20 g de EPA + DHA / 100 g microcápsulas, sendo necessária a adição de menos de 0,5 g de microcápsulas em porções de 100 g ou 100 mL de alimentos para este poder ser considerado funcional. Contudo, uma grande variação no processo foi observadalevando a um estudo mais aprofundado do processo de coacervação através do potencial zeta dos materiais de parede e de recheio separadamente e em diferentes misturas, onde foi constatado que o isolado protéico de soja, por possuir variação na sua constituição e baixa solubilidade, dificulta a determinação exata do potencial zeta zero das misturas, sendo a máxima eficiência de encapsulação encontrada quando as misturas de 1,5:1,0 (massa:massa) isolado protéico de soja:Goma arábica e 2,0:1,0 (massa:massa) material de parede:material de recheio em pH 4,0 foram testados / Abstract: Fats and oils are important energy sources in human feeding, and some, such as the omega-3 polyunsaturated fatty acids, are considered essential to the functioning of the organisms. Eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids from marine sources are the principal forms used for the direct ingestion of omega-3, but are highly sensitive to oxidation and present characteristic flavors leading to their rejection by some consumers. One alternative to overcome these problems is microencapsulation, and one well known technique for this type of sensitive product is coacervation, although some new techniques are currently appearing which also attempt to overcome these deficiencies.Enzymatic gelation could be cited as a new technology which aims to reduce some of the processing steps and production time when compared to coacervation. This work aimed to understand the behavior of the core material (fish oil ethyl ester),since few studies can be found referring to analyses of the integrity of the core materials of a lipid nature when encapsulated, and of the wall materials (principally soy protein isolate and whey protein isolate), when used in the production of microcapsules by enzymatic gelation and by complex coacervation, evaluating both the electrostatic charges in the medium from their zeta potential for coacervation, and a complete characterization of the resulting capsules produced by both enzymatic gelation and coacervation. Of the wall materials studied, whey protein isolate and soy protein isolate were used, the latter, at a concentration of 10%, producing microcapsules with the best characteristics by the enzymatic gelation technique. However, when the characteristics of the microcapsules produced by enzymatic gelation were studied at greater depth, the analysis of the core material showed that lipid material from another source had been coencapsulated due to the processing conditions, thus reducing the true efficiency of the encapsulation, showing that this technique was not efficient, despite the elevated mechanical resistance of the microcapsules. A comparison of the methods used to degrade the capsules showed total degradation of the wall by the acid degradation methodology, and only partial degradation for the enzymatic alkaline degradation methodology. Thus the best degradation methodology to determine the composition of the encapsulated material was acid degradation with the direct determination of the fatty acid composition. In the statistical study of the production of microcapsules containing fish oil ethyl ester by complex coacervation using soy protein isolate and gum Arabic as the wall materials, capsules were obtained containing more than 20 g EPA + DHA / 100 g of microcapsules, requiring the addition of less than 0.5 g of microcapsules to 100 g or 100 mL portions of foods for the food to be considered functional. However considerable process variation was observed, leading to a study in greater depth of the coacervation process as from the zeta potential of the wall and core materials separately, and in different mixtures. Thus it was shown that the soy protein isolate presented variation in its constitution and low solubility, which made it difficult to determine the exact zero zeta potential of the mixtures, the maximum encapsulation efficiency being found with mixtures of 1.5:1.0 (w:w) soy protein isolate: gum Arabic as the wall material and a ratio of 2.0:1.0 (w:w) for the wall material: core material at pH 4.0 / Doutorado / Tecnologia de Alimentos / Doutora em Tecnologia de Alimentos
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Ácido eicosapentanóico x deflazacorte : mecanismos de ação e comparação de efeitos no tratamento de camundongos mdx / Eicosapentaenoic acid x deflazacort : mechanisms of action and effects in the dystrophic mdx miceApolinário, Letícia Montanholi, 1988- 21 August 2018 (has links)
Orientador: Maria Julia Marques / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-21T09:08:14Z (GMT). No. of bitstreams: 1
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Previous issue date: 2012 / Resumo: A Distrofia Muscular de Duchenne (DMD) é uma doença recessiva ligada ao cromossomo X. Os glicocorticoides são amplamente utilizados para o tratamento da DMD, entretanto os efeitos colaterais decorrente de seu uso contínuo motivam a busca por novas terapias farmacológicas. Ácidos graxos poli-insaturados têm sido empregados para o tratamento de várias doenças, exercendo seus efeitos através de mecanismos pouco conhecidos... O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital / Abstract: Duchenne Muscular Dystrophy (DMD) is an X-linked recessive disease that leads to myonecrosis and cardiorespiratory failure. Glucocorticoids are so far the choice treatment for DMD. However their side effects due to continuous use motivate the search for new therapies¿ The complete
Abstract is available with the full electronic document / Mestrado / Anatomia / Mestra em Biologia Celular e Estrutural
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