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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.
21

BARN OCH ASTMA - FINNS DET EVIDENS FÖR OMEGA-3 BEHANDLING? : EN SYSTEMATISK LITTERATURÖVERSIKT / CHILDREN AND ASTHMA - IS THERE ANY EVIDENCE FOR TREATMENT WITH OMEGA 3 FATTY ACIDS? : A SYSTEMATIC REVIEW

Kristensson, Matilda, Henningsson, Angelica January 2022 (has links)
Bakgrund: Astma är en inflammationssjukdom i luftvägarna, och en av de vanligaste kroniska sjukdomarna hos barn globalt sett. Vanligast är astma hos barn mellan 3 och 15 år, men hälften av alla barn som diagnostiserats med astma som barn har även betydande besvär upp i vuxen ålder. För en del av populationen har inte traditionell läkemedelsbehandling någon effekt, varför alternativa behandlingsmetoder så som omega-3 tillskott bör undersökas. Syfte: Syftet med innevarande litteraturstudie var att kartlägga om det finns evidens för om omega-3 tillskott kan användas i förebyggande eller symtomlindrande syfte hos barn (0–18 år) som löper hög risk för att utveckla astma eller som är diagnostiserade med astma. Metod: Studien utformades som en systematisk litteraturstudie. Litteratursökningar har genomförts i databaserna Pubmed, CINAHL och Medline. Sökningarna bestod av sökblocken astma, barn eller ungdomar och omega-3 tillskott/omega-3 fettsyror. Resultat: Denna studie inkluderar fem RCT-studier med syftet att undersöka om omega-3 tillskott kunde förebygga astma eller minska symtomen av astma hos barn, totalt 939 barn med astma har studerats i de fem studierna. Fyra studier påvisade att omega-3 tillskott till barn med astma inte har någon klinisk relevans medan en studie påvisade att klinisk relevans fanns. Slutsats: Denna systematiska litteraturstudie resulterade i att det inte finns någon evidens för att omega-3 tillskott skulle verka förebyggande eller symtomlindrande för barn med astma. RCT-studierna som inkluderats i denna systematiska litteraturöversikt är mycket heterogena och därför behövs vidare forskning på omega-3 tillskotts kliniska relevans. / Background: Asthma is an inflammatory disease in the airways, and is one of the most common chronic diseases in children globally. Asthma is most common in children between 3 to 15 years of age, but 50 % of children diagnosed with asthma as a child also have significant problems as adults. For some part of the population traditional drug treatment has no effect, indicating that alternative treatment methods, such as omega-3 supplements, should be investigated further. Aim: The aim of the current literature study was to investigate if there is any evidence of whether omega-3 supplements can be used for preventive or symptom-relieving purposes in children (0-18 years of age), who are at high risk of developing asthma or who have been diagnosed with asthma. Methods: The study was designed as a systematic review. Literature searches have been conducted using the Pubmed, CINAHL and Medline databases. The searches consisted of the search blocks asthma, children or adolescents and omega-3 supplements/omega-3 fatty acids. Results: This study includes five RCT studies that was aimed to investigate whether omega-3 supplements could prevent asthma or reduce the symptoms of asthma in children, a total of 939 children with asthma have been studied in the five studies. Four studies showed that omega-3 supplements for children with asthma have no clinical relevance, while one study showed that clinical relevance existed. Conclusion: This systematic review proved that no evidence for omega-3 supplements treatment, for preventive or symptom relieving purposes, in children with asthma exists. The RCT studies included in this systematic review are very heterogeneous and therefore further research on the clinical relevance of omega-3 supplement is needed.
22

The structure and function of omega-3 polyunsaturated fatty acids in model and cellular membranes

Ehringer, William Dennis January 1993 (has links)
This document only includes an excerpt of the corresponding thesis or dissertation. To request a digital scan of the full text, please contact the Ruth Lilly Medical Library's Interlibrary Loan Department (rlmlill@iu.edu).
23

Development of Omega-3-Fatty Acid Enriched Finishing Feed and Value Added Tilapia Product

Stoneham, Tyler R. 29 June 2016 (has links)
Despite being a low fat fish and consequently a low omega-3 fish, tilapia have widespread consumer acceptability due to its mild taste, cheap price and low mercury content. However some sources claim that farmed tilapia can be detrimental to human health due to high omega-6:3 ratios and low omega-3 content specifically eicosapentaenoic acid, docosapentaenoic acid, and docosahexaenoic acid. The objective of this study was to create an omega-3 enriching feed that would increase omega-3 content in tilapia and subsequently decrease the omega-6:3 ratio. An 8 week feeding trial was conducted. Tilapia were cultured in a recirculating aquaculture system on one of eight diets (control, commercial, 1, 3, 5% fish oil or 1.75, 5.26, 8.77% ALL-G-Rich (algae). Water quality, selected fish biometrics and growth performance were recorded. Fillet and rib meat tissues were collected at weeks 4 and 8, and liver and mesenteric fat tissues were collected at week 8. Fat was extracted, trans-methylated and identified as fatty acid methyl esters using gas chromatography-mass spectrometry. Docosahexaenoic acid increased in concentration in all tissues as percent fish oil and ALL-G-Rich increased in the diets with 8.77% ALL-G-Rich resulting in significantly (P<0.0001) greater concentrations in the fillet and mesenteric fat compared to all other diets after 8 weeks. The 8.77% ALL-G-Rich diet resulted in significantly (P=0.003) greater cumulative accumulation of EPA, DPA and DHA on a mg/4oz fillet basis after 4 weeks compared to control. The results of this study suggest that an ALL-G-Rich finishing feed could be produced that would result in a value added farmed tilapia fillet. / Master of Science in Life Sciences
24

Fate of Omega-3 Fatty Acids from Algae in Mozzarella Cheese

Orders, Margaret 25 September 2008 (has links)
Increased consumer interest in omega-3 fatty acids (FA) has led to novel foods with added omega-3 FA. Additional information regarding omega-3 FA fate within foods is needed for improving quality and stability. This research modeled DHA, an omega-3 FA, fate and explored means of preventing degradation and oxidation of FA in algal oil and mozzarella cheese. In algal oil, TBHQ (synthetic antioxidant) at 0.0175g/g algal oil prevented DHA degradation for at least 6 weeks, and mixed tocopherols (natural antioxidant) at 400ppm prevented DHA degradation and oxidation for about 4 weeks. DHA degradation in algal oil was modeled by an autocatalytic equation. The fate of DHA from algal oil in mozzarella cheese was also modeled by an autocatalytic equation. In an effort to prevent DHA degradation and oxidation, mixed tocopherols were added. The optimum combination of those tested was found, using a response surface design, to be 3% algal oil with 110ppm mixed tocopherols for maximum DHA and minimum oxidation over 2 weeks. This algal oil/antioxidant combination in mozzarella cheese successfully prevented oxidation and DHA degradation over 3 weeks of storage. Approximately 0.1g DHA may be consumed from a 28g serving of this cheese. Approximately 0.5-18 servings of this cheese are equivalent to DHA consumed from a 3oz serving of fish, depending on fish type. Sensory evaluation tests found consumers could distinguish between mozzarella cheese with/without algal oil. Results from this study improve understanding of omega-3 FA behavior in mozzarella cheese and provide a means for preserving quality and nutrition. / Master of Science
25

Hur påverkar kosten symptom hos barn med ADHD? / How does diet affect symptoms for children with ADHD?

Hector, Johanna, Persson, Marie January 2016 (has links)
Inledning: Drygt 5% av barn i Sverige har en uppmärksamhets- och hyperaktivitetsstörning/ Attention Deficit Hyperactivity Disorder(ADHD), och runt 75% av dem medicineras för att minska symptomen av ADHD. Hyperaktivitet, svårigheter att fokusera och koncentrera sig, och impulsivt beteende är några karaktärsdrag hos barn med ADHD. Syfte: Syftet med litteraturöversikten är att se om det finns kostrelaterade behandlingskomplement för att lindra ADHD hos barn. Metod: En litteraturöversikt där tio vetenskapliga originalartiklar har analyserats och delats upp i fyra olika teman. Resultat: En elimineringskost där vissa födoämnen uteslutadess, ett minskat intag av tillsatser (konstgjorda färgämnen och konserveringsmedel) eller ökat intag av omega-3 visade positiva effekter hos en grupp barn med ADHD där symptomen minskade, speciellt hyperaktivitet. Diskussion: Trots att resultaten av studierna visar en positiv effekt hos vissa barn med ADHD så behövs mer grundlig forskning angående elimineringskost, tillsatser och omega-3. Studierna baseras ofta på frågeformulär som fylls i av föräldrarna vilket kan leda till subjektiva resultat som tar bort generaliserbarheten av studierna. De positiva effekterna antyder att komplementära behandlingsmetoder kan finnas genom en förändrad kost, som förbättrar livskvaliteten och minskar biverkningar hos barn med ADHD och samtidigt sänker kostnaderna för samhället. / Introduction: About 5% of all children in Sweden are diagnosed with Attention Deficit Hyperactivity Disorder (ADHD) and about 75 % get medication do reduce symptoms. Hyperactivity, difficulties to focus and concentrate and impulsive behavior are typical characteristics for children with ADHD. Aim: The aim with this literature review is to see if complementary treatments based on diet can assist to reduce symptoms of ADHD for children. Method: A literature review that analyses ten original articles which are divided into four different topics. Result: An elimination diet that excludes certain foods, reduced intake of food additives and preservatives or increased intake of omega-3 showed positive effects for a group of children with ADHD as symptoms minimized especially for hyperactivity. Discussion: Even though results of the studies show positive effects for certain children with ADHD, more research is needed that further investigates the effects of elimination diet, food additives and omega-3. The studies were mainly based on questionnaires, filled in by parents, which can lead to subjective results. The positive effects suggest that alternative treatments by changed diet might assist children with ADHD, improving life quality and reducing medication side effects together with reduced costs for society.
26

Stability of essential nutrients in pet food manufacturing and storage

Mooney, Alaina January 1900 (has links)
Master of Science / Grain Science and Industry / Greg Aldrich / Processing pet food can be beneficial, but can also have adverse effects on shelf-life and nutrient survival. Most affected are supplemental vitamins and essential fatty acids (EFA). Pet food complicates this relative to human foods by combining all elements into the product before processing and requiring an extensive shelf-life (up to 2 years). The objective of this research was to determine the effects of processing, diet, and storage conditions on vitamin (vitamin A, vitamin D₃, vitamin E, folic acid and thiamine) and omega-3 fatty acid (with an emphasis on eicosapentaenoic acid; EPA 20:5n3, and docosahexaenoic acid; DHA; 22:6n3) retention. The research was conducted in two separate experiments. Each experimental diet was produced on a single-screw extruder and triple-pass dryer. Target nutrients were evaluated in premixes in tandem to extruded diets. The vitamin study was conducted as a 3 X 2 X 2 factorial arrangement of treatments with 3 levels of dietary crude protein (CP), 2 screw speeds in the extruder, and 2 levels of time X temperature combinations in the dryer. Vitamins were added at 10 times normal levels to aid in analysis. The EFA study was conducted as a 3 X 3 factorial arrangement of treatments with 3 levels of dietary protein and 3 different omega-3 sources: fish oil, fish meal, or purpose-grown algae rich in DHA. In the vitamin premix study, the quantity of vitamins declined by approximately 50% over 6 months storage in ambient conditions (AMB; 20C, 50%RH), and all except folic acid were lost to some degree in stressed shelf life testing (SSLT; 50C, 70% RH) over 6 weeks. In all cases, the concentration of vitamins in food exiting the extruder and dryer were lower than target levels. As CP increased, the retention was higher (P ≤ 0.05) for vitamins A, E, and folic acid off the extruder (e.g. 225,352 vs. 219,184 and 206,249 IU/kg of vitamin A for high vs. medium and low CP, respectively), and vitamin D₃, E, and folic acid off the dryer (e.g. 9,047 vs. 7,473 and 6,945 IU/kg of vitamin D₃ for high vs. medium and low CP, respectively). During storage of finished pet food in AMB, vitamins A and D₃ were lost (P < 0.05) to the greatest degree (49 and 22%, respectively). The total retention following both processing and AMB storage was 27, 68, 78% for vitamins A, D₃, and E, respectively, while folic acid and thiamine were relatively stable. In SSLT storage, all vitamins except vitamin E were depleted more than 60% (P < 0.05) by 24 weeks, whereas total retention following both processing and SSLT storage was 3, 59, 43, 33, and 7% for vitamins A, D₃, and E, folic acid, and thiamine, respectively. This would suggest that beyond processing losses, the vitamins are relatively stable in premixes and foods if stored in AMB conditions. In the study to evaluate fatty acid stability within a vitamin premix, EPA, DHA, and total omega-3 fatty acids were relatively stable during storage over 6 weeks with losses no greater than 12% in stressed shelf life testing (SSLT; 40C, 70% RH). While in ambient conditions (23C, 50% RH) over 3 months, there was a total loss of EPA, DHA and total fatty acids by 17, 9, and 11%, respectively. Exiting the extruder and dryer, EPA and DHA were not affected by CP level or Omega-3 source. As SSLT storage of finished pet food increased through 24 weeks, EPA, DHA, and total fatty acids declined slightly (P < 0.05; 125, 82 mg/kg for EPA and 77, 60 mg/kg for DHA, and 418, 476 mg/kg for total fatty acids at 0 vs. 24 wk. As time in ambient storage reached 24 months, EPA, DHA, and total fatty acids declined slightly (P < 0.05; 125 vs. 78 mg/kg for EPA and 77 vs. 50 mg/kg for DHA, and 387 vs. 373 for total fatty acids at 0 vs. 24 mo.) Algal-DHA appears to be a stable source of DHA when compared to fish oil and fishmeal. During processing retention of fat soluble vitamins was less than water soluble vitamins, and the omega-3 fatty acids were relatively unaffected. Whereas, vitamins appeared to be more sensitive to temperature during storage and the omega 3 fatty acids more affected by time.
27

Antioksidacinio aktyvumo nustatymas preparatuose, turinčiuose omega – 3 riebalų rūgščių / Evaluation of antioxidant activity of preparations containing omega - 3 fatty acid

Kiškytė, Karolina 18 June 2014 (has links)
Darbo tikslas: nustatyti antioksidacinį preparatų, turinčių omega – 3 riebalų rūgščių, aktyvumą, palyginti jį su preparatų sudėtimis, atlikti vaistinės asortimento analizę. Darbo uždaviniai: Atlikti preparatų antioksidacinio aktyvumo tyrimą DPPH metodu. Atlikti preparatų palyginamąją analizę vertinant sudėtis. Išnagrinėti omega – 3 riebalų rūgščių turinčių preparatų pasiūlą vaistinėse. Metodai: antioksidacinis aliejų aktyvumas tirtas spektrofotometriškai naudojant 2,2-difenil-1-pikrilhidrazilo (DPPH) laisvojo radikalo sujungimo metodą. Pasirinktų linų sėmenų, kanapių sėklų, judros, rapsų, kviečių gemalų, graikinių riešutų aliejų bei žuvų taukų sudėtys vertintos ir lygintos literatūros analizės metodu. Tyrime naudotų aliejų paplitimas vaistinės asortimente nustatytas renkant duomenis vaistinėse bei elektroninėse vaistinių parduotuvėse. Rezultatai: nustatytas antioksidacinis aktyvumas (išreikštas inaktyvuoto DPPH % ±SD) kviečių gemalų aliejaus 53,59 ± 9,45, žuvų taukų 22,58 ± 5,38, judros aliejaus 22,40 ± 4,74, linų sėmenų aliejaus 22,17 ± 2,64, kanapių sėklų aliejaus 19,05 ± 1,54, graikinių riešutų aliejaus 18,66 ± 4,10, rapsų aliejaus 17,04 ± 2,68. Palyginus rezultatus ir literatūroje pateiktus duomenis nustatyta, kad nėra ryšio tarp aliejuje esančio omega – 3 riebalų rūgščių kiekio ir antioksidacinio aktyvumo, tačiau yra statistiškai patikimas ryšys tarp antioksidacinio aktyvumo ir sudėtyje esančio vit.E kiekio. Įvertinus vaistinės asortimentą nustatyti 75 žuvų taukų... [toliau žr. visą tekstą] / Objective of work: To estimate the antioxidant activity of preparations containing omega - 3 fatty acids; compare it with constitution of preparations; to execute the analysis of pharmacy range. Main tasks: to estimate the antioxidant activity by using DPPH method. To compare preparations by evaluating their constitutions. To execute the analysis of pharmacy range. Methods: antioxidant activity determined by using 2,2 – diphenyl-1-picrylhidrazyl free radical scavenging method. The constituents of flax seed, hemp seed, camelina, rapeseed, wheat germ, walnut and fish oil were evaluated by literature analysis. The data of prevalence of selected oils in pharmacy range was collected in the pharmacies and their online-shops. Results: antioxidant activity of wheat germ oil was 53,59 ± 9,45%, fish oil 22,58 ± 5,38%, camelina oil 22,40 ± 4,74%, flax seed oil 22,17 ± 2,64%, hemp seed oil 19,05 ± 1,54%, walnut oil 18,66 ± 4,10%, rapeseed oil 17,04 ± 2,68%. A comparison of the results showed that there is no significant relationship between amount of omega – 3 fatty acids and the antioxidant activity of the oil, but there is a statistically significant relationship between the amount of tocopherols and the antioxidant activity. The evaluation of the pharmacy range showed 75 fish oil products, 10 products containing flax seed oil, 9 wheat germ oil, 6 hemp seed oil, 3 products with camelina oil, 2 rapeseed oil, and only one product containing walnut oil. Conclusions: The highest... [to full text]
28

Measurement of fish consumption in population-based studies of cancer /

Mina, Kym Deanne. January 2007 (has links)
Thesis (Ph.D.)--University of Western Australia, 2007.
29

Fontes de óleo na dieta e sua importância no desempenho e na imunidade de frangos de corte

Ribeiro, Sheila Cardoso [UNESP] 20 August 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-08-20Bitstream added on 2014-06-13T19:14:36Z : No. of bitstreams: 1 ribeiro_sc_me_araca.pdf: 191988 bytes, checksum: 6ae04c780c812f7133db1a6434eef76f (MD5) / Foi avaliado o efeito do uso de óleos ricos em ácidos graxos polinsaturados ômega-3 na dieta de frangos de corte sobre o desempenho e a resposta imune humoral e celular à vacinação. Foram comparadas dietas formuladas com óleo de soja (OS), linhaça (OL) ou sardinha (OP), fornecidas a 240 frangos da linhagem Cobb, divididos em 24 grupos de 10 aves cada, num arranjo experimental 3x2 (3 tipos de óleo e 2 situações vacinais) e 4 repetições. O consumo de ração, o ganho de peso e a conversão alimentar foram avaliados aos 21, 35 e 42 dias. Metade dos grupos foi vacinado contra doença de Newcastle. A produção de anticorpos, avaliada 15 dias após a vacinação pelo método de ELISA e expressa em densidade óptica a 450nm (D.O.450nm), foi maior entre as aves alimentadas com ração com OS (P<0,05). Nos grupos alimentados com OL e OP as médias de D.O.450nm não diferiram significativamente entre vacinados e não vacinados (P>0,05). A resposta linfoproliferativa das aves vacinadas foi maior independente do tipo de óleo utilizado (P<0,05). Na análise de desempenho não houve interferência da fonte de óleo ou da vacinação sobre o ganho de peso e peso vivo. Entre as aves vacinadas a pior média de conversão alimentar correspondeu à dieta com OS. Além disso, entre as aves que receberam dieta com OS, a vacinação piorou significativamente a conversão alimentar, considerando todo o período experimental (P<0,05). Já entre as aves que receberam dieta com OL ou OP, não houve diferença na conversão alimentar entre os grupos vacinados e não vacinados (P>0,05). Estes resultados demonstram que a reação maior ao desafio vacinal prejudicou o desempenho das aves alimentadas com OS. / The effect of the use of oils rich in omega-3 polyunsaturated fatty acids in the diet of broiler on performance and humoral immunity and cellular response to vaccination were evaluated. Diets were compared with soybean oil (OS), linseed (OL) or sardine (OP), supplied to 240 broiler, Cobb, divided into 24 groups of 10 birds each in a 3x2 factorial arrangement (3 types of oil and two vaccine situations) and 4 replications. Feed intake, weight gain and feed conversion were evaluated at 21, 35 and 42 days. Half of the groups were vaccinated against Newcastle disease. The production of antibodies evaluated 15 days after vaccination by ELISA and expressed as optical density at 450 nm (D.O.450nm) was higher in birds fed OS (P<0.05). In groups fed OL and OP, the mean of D.O.450nm did not differ significantly between vaccinated and unvaccinated (P>0.05). The lymphoproliferative response of vaccinated birds was higher, regardless of the type of oil used (P<0.05). In the performance analysis, there was no interference from the source of oil or of vaccination on weight gain and body weight. Among those vaccinated, the worst average feed conversion corresponded to the diet OS. Moreover, among the birds fed OS, vaccination has significantly worsened feed conversion, considering the entire experimental period (P<0.05). Among the birds fed OL or OP, there was no difference in feed conversion between vaccinated and unvaccinated groups (P>0.05). These results demonstrate that the greatest reaction to the challenge vaccine affected performance of birds fed OS.
30

Rôle des acides gras polyinsaturés alimentaires dans l'homéostasie lipidique de la rétine en conditions physiologiques et pathologiques liées au vieillissement / Role of dietary polyunsaturated fatty acids in the retina lipid homeostasia in physiological and pathological conditions associted with aging

Thierry, Magalie 19 November 2014 (has links)
La rétine est constituée de l’association d’un tissu neurosensoriel et de l’épithélium pigmentaire rétinien (EPR). Malgré la présence d’une barrière hémato-rétinienne, la rétine est contrainte aux changements de son milieu environnant, incluant les modifications du régime alimentaire et les stress environnementaux. Au cours du vieillissement, les échanges de nutriments et l’élimination des déchets métaboliques et cellulaires au travers de l’EPR diminuent. La dégénérescence maculaire liée à l’âge (DMLA) et la rétinopathie diabétique (RD) sont les pathologies rétiniennes les plus prévalentes dans les populations occidentales avant et après l’âge de 50 ans, respectivement. L’atrophie géographique et la DMLA néovasculaire constituent les stades avancés des maculopathies liées à l’âge. La RD affecte 60% des patients atteints de diabète de type 2 (T2D) dans les 15 années suivant l’apparition de la pathologie. Par ailleurs, les facteurs alimentaires interfèrent avec le développement de la DMLA et du T2D. Considérant l’épidémie mondiale de T2D d’une part, et l’allongement de l’espérance de vie d’autre part, les dépenses médico-sociales relatives à la prise en charge des patients atteints de T2D ou de DMLA sont à même de devenir un enjeu socioéconomique majeur. Le syndrome métabolique (SMet) est un des principaux facteurs de risque du T2D. Il peut ainsi être suggéré que limiter le développement du SMet pourrait potentiellement limiter l’incidence du T2D et de ses complications. Dans ce contexte, la consommation d’acides gras polyinsaturés à longue chaîne (AGPI-LC) de type oméga 3 fait partie des recommandations nutritionnelles pour la population afin de prévenir l’apparition du SMet et du T2D. Par ailleurs, une alimentation riche en AGPI-LC omega-3 est également associée à la réduction du risque de DMLA. En revanche, l’association entre T2D, RD et DMLA reste controversée, bien que quelques études basées sur des grandes cohortes rapportent une prévalence de DMLA augmentée chez les patients atteints de diabète ou de RD. Nos objectifs ont été d’évaluer premièrement si un SMet constituait un environnement favorable au développement des complications de type néovasculaires dans la rétine, et de tester secondairement l’efficacité d’AGPI-LC omega-3 dans la réduction des conséquences de ce SMet sur la rétine. Pour atteindre cet objectif, des rats ont été nourris avec un régime diabétogène enrichi en fructose afin de provoquer un SMet. Une néovascularisation choroïdienne a ensuite été induite en utilisant un modèle d’impacts laser au fond d’œil. Nous nous sommes intéressés tout d’abord à l’effet de ce régime à court terme et avons mis en évidence une diminution de la sensibilité des photorécepteurs de type cônes après 8 jours de régime, ainsi qu’une modification de l’expression des gènes et en particulier des sous-familles de cristallines. Ensuite, nos études se sont portées sur les effets de régime enrichi en fructose à long terme jusqu’à 6 mois. Le développement d’un SMet a été illustré par une augmentation de la masse grasse, une hyperinsulinémie, une hyperleptinémie et l’installation d’une stéatose hépatique. Ces rats ont développé une néovascularisation choroïdienne exacerbée après 1 et 3 mois de régime associée à une surexpression de facteurs pro-angiogéniques tels que VEGF et leptine .Une infiltration de macrophages dans la rétine et/ou l’activation des cellules microgliales résidentes a également été détectée. Les données électrorétinographiques ont suggéré une diminution de la sensibilité des photorécepteurs de type bâtonnets ainsi qu’une altération des fonctionnalités des cellules de la rétine interne à 6 mois. Dans un second temps, l’efficacité des AGPI-LC omega-3 (EPA+DHA) dans le but de réduire les conséquences du SMet dans la rétine a été testée. Nos données mettent en évidence qu’une forte dose d’EPA+DHA n’a cependant pas amélioré le SMet chez le rat. / The retina is the association of the neurosensory tissue and the retinal pigment epithelium (RPE). Despite the presence of the blood retinal barrier, the retina is submitted to changes of the external milieu, including dietary modulation and environmental stresses. With advanced age, the exchanges of nutrients and elimination of cellular and metabolic wastes via the RPE become limited. Age-related Macular Degeneration (AMD) and Diabetic Retinopathy (DR) are the most prevalent retinal pathologies in Western adult populations before and after the age of 50 years, respectively. Geographic atrophy and neovascular AMD are advanced stages of age-related maculopathies. DR afflicts 60% of type 2 diabetic (T2D) patients in the first 15 years of the disease. Dietary factors interfere in the development of both AMD and T2D. Accounting the worldwide epidemics of T2D in the one hand, and the improvement of life expectancy in the other hand, medical care to the patients is expected to worsen the socioeconomic burden of both T2D and AMD. Metabolic syndrome (MetS) is one of the major risk factor for T2D. Lowering the development of MetS would potentially lessen the incidence of T2D, and its complications. The daily intake of omega 3 long chain polyunsaturated fatty acids (LC-PUFA) is now recommended by health agencies for the prevention of MetS. Meanwhile dietary omega 3 LC-PUFA are associated with reduced risk of AMD. The association between T2D, DR, and AMD remains controversial, although large-scale population-based studies have reported increased prevalence of AMD in patients with diabetes or DR. Our objectives were first to evaluate whether MetS would represent a favorable environment for the development of neovascular complications in the retina, and second to test the efficacy of omega 3 LC-PUFA to reduce the consequences of MetS in the retina. For that purpose, a pro-diabetogenic high fructose diet was fed to rats to induce MetS and choroidal neovascularization was triggered by laser impacts in the eye fundus. We focused first on short term diet periods, and showed impairment on cone photoreceptor sensitivity after 8 days, as well as changes in gene expression in relation to crystallin sub-families. A long term - up to 6 months - fructose diet period triggered MetS as illustrated by body fat increase, hyperinsulinemia, hyperleptinemia and liver steatosis. Rats exhibited exacerbated laser-induced choroidal neovascularization after 1 and 3 months of feeding, that was associated with up-regulation of genes coding pro-angiogenic factors such as VEGF and leptin, as well as infiltration of macrophages and/or activation of retinal microglia. Electroretinographic data showed decreased sensitivity of rod photoreceptors and inner retinal cell functionality at 6 months of feeding. In a second time, the efficacy of dietary omega 3 LC-PUFA (EPA plus DHA) to reduce the consequences of MetS in the retina was tested. Our data showed that a high dose of EPA+DHA in rats did not improve MetS. Furthermore, side effects were generated as illustrated by localized atrophy in the retina submitted to the combination of laser-impacts, and normal light exposure. These works allowed us to suggest that MetS generated a favorable environment in the retina for the development of neovascular complications. Meanwhile, the sensitivity of cones and rods was impaired by MetS. Accounting the deleterious long term effects of omega 3 LC-PUFA in the retina, caution may be taken while recommending massive supplementation with omega 3 LC-PUFA in the context of MetS.

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