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Relevant bibliographies by topics / Stress nutritionnel

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Academic literature on the topic 'Stress nutritionnel'

Author: Grafiati

Published: 4 June 2021

Last updated: 4 May 2024

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Journal articles on the topic "Stress nutritionnel"

1

Omari, N., A. Fares, S. Benazzouk, E. Koceir, and Z. Sellal. "Stress nutritionnel chez les patients initialement hypertendus." Annales d'Endocrinologie 73, no. 4 (September 2012): 412. http://dx.doi.org/10.1016/j.ando.2012.07.687.

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Pouysségur, Jacques. "Le stress hypoxique et nutritionnel tumoral. Nouvelles approches anticancer." Annales de Pathologie 30, no. 5 (November 2010): 18–21. http://dx.doi.org/10.1016/j.annpat.2010.07.028.

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Semiane, N., S. Ameddah, A. Mallek, and Y. Dahmani. "L’induction d’une insulino-résistance et d’un stress oxydatif pancréatique chez la gerbille (Gerbillus gerbillus) soumise à un stress nutritionnel." Annales d'Endocrinologie 77, no. 4 (September 2016): 530–31. http://dx.doi.org/10.1016/j.ando.2016.07.855.

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Medjerab, M., S. Hammadi, N. Semiane, A. Khalkhal, A. Mallek, T. Hacini, Z. Bellahreche, H. Agoun, and Y. Dahmani. "Études histologique et histochimique de la glande surrénale chez Gerbillus gerbillus soumise à un stress nutritionnel." Annales d'Endocrinologie 74, no. 4 (September 2013): 332. http://dx.doi.org/10.1016/j.ando.2013.07.311.

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Semiane, N., M. Medjerab, H. Agoun, S. Hammadi, Z. Bellahreche, A. Mallek, A. Khalkhal, F. Sekkal, M. Bouyoucef, and Y. Dahmani. "P098 Rôle du stress nutritionnel dans le développement de l’obésité et l’insulinorésistance chez un rongeur déserticole nocturne (gerbillus gerbillus)." Cahiers de Nutrition et de Diététique 48 (December 2013): S105. http://dx.doi.org/10.1016/s0007-9960(13)70456-5.

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Semiane, N., M. Medjerab, H. Agoun, S. Hammadi, Z. Bellahreche, A. Mallek, A. Khalkhal, F. Sekkal, M. Bouyoucef, and Y. Dahmani. "P098 Rôle du stress nutritionnel dans le développement de l’obésité et l’insulinorésistance chez un rongeur déserticole nocturne (gerbillus gerbillus)." Nutrition Clinique et Métabolisme 27 (December 2013): S105. http://dx.doi.org/10.1016/s0985-0562(13)70430-8.

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Hesketh, John E., and Stéphane Villette. "Intracellular trafficking of micronutrients: from gene regulation to nutrient requirements." Proceedings of the Nutrition Society 61, no. 4 (November 2002): 405–14. http://dx.doi.org/10.1079/pns2002176.

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RésuméLa distribution intracellulaire des micronutriments ainsi que leur absorption sont importantes pour les fonctions cellulaires. Dans certains cas la distribution des micronutriments ou des protéines associées est déterminée par des mécanismes liés à l'expression des gènes. La région 3' non traduite (3'UTR) de l'ARNm de la métallothioneine-1 détermine la localisation de ce message et, par conséquent, la localisation intracellulaire de la protéine qu'il code. En utilisant des cellules transfectées nous avons montré que la métallothioneine-1 est transportée vers le noyau ou elle exerce un rôle dans la protection contre le stress oxydant et les dommages causés à l'ADN. Quand l'apport nutritionnel en Se est limité, l'expression des sélénoproteines est altérée. Toutefois celle-ci n'est pas affectée de fac¸on identique pour toutes les sélénoproteines; le Se disponible étant utilisé de fac¸on prioritaire pour la synthèse de certaines d'entre elles. Cet ordre de priorité met en jeu des différences dans la traduction et la stabilité de leur ARNm qui sont sous le controle de séquences dans la région 3' non traduite. Potentiellement, des variations génétiques affectant ces mécanismes régulateurs peuvent moduler les besoins en nutriments. Des polymorphismes génétiques ont été décrits dans le 3'UTR des ARNm de deux sélénoproteines; l'un d'entre eux affectant la synthèse de la sélénoproteine correspondante. Ces exemples illustrent comment des approches moléculaires peuvent contribuer à accroître notre compréhension du métabolisme et des besoins en nutriments à différents niveaux. Premièrement, elles permettent d'étudier les effets régulateurs des gènes et de leurs produits. Ensuite, la compréhension de ces effets peut fournir un modèle pour étudier le métabolisme des nutriments au niveau cellulaire. Ainsi, lorsque des effets essentiels sont identifiés, la connaissance du génome humain et les bases de données sur les polymorphismes génétiques constituent des outils complémentaires pour définir l'étendue de la variation génétique des gènes revêtant une importance nutritionnelle. Enfin, la fonctionnalité de ces variations peut être définie et des sous-groupes de la population, possédant des besoins nutritionnels différents, peuvent etre identifiés.

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GUILHERMET, R. G. "Fonctions nutritionnelles et métaboliques de l’arginine." INRAE Productions Animales 9, no. 4 (August 17, 1996): 265–72. http://dx.doi.org/10.20870/productions-animales.1996.9.4.4060.

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L’arginine est un acide aminé qualifié d’ éventuellement indispensable, parce que la synthèse endogène rénale qui existe est insuffisante pour permettre une croissance normale au jeune mammifère. Les régimes distribués aux animaux en croissance intensive, avec des niveaux d’ingestion élevés, fournissent suffisamment d’arginine. Cependant en cas d’alimentation modérée, des suppléments d’arginine sont susceptibles d’accroître la rétention azotée. En outre, l’amélioration de l’état nutritionnel permise par l’arginine supplémentaire en phase post-traumatique montre une augmentation importante du besoin dans cette situation de stress, ainsi qu’une implication de cette molécule dans les processus d’accrétion tissulaire. Les différentes voies du métabolisme de l’arginine conduisent à des composés tels que l’ornithine, la proline, le glutamate, les polyamines et le NO, dont le potentiel d’action au niveau cellulaire est considérable. Ils sont susceptibles de produire de nombreux effets biologiques et d’expliquer en partie les multiples activités physiologiques autres que nutritionnelles de l’arginine.

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GUILHERMET, R. G. "Fonctions nutritionnelles et métaboliques de l’arginine." INRAE Productions Animales 9, no. 4 (August 20, 1996): 265–72. http://dx.doi.org/10.20870/productions-animales.1996.9.4.4067.

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L’arginine est un acide aminé qualifié d’ éventuellement indispensable, parce que la synthèse endogène rénale qui existe est insuffisante pour permettre une croissance normale au jeune mammifère. Les régimes distribués aux animaux en croissance intensive, avec des niveaux d’ingestion élevés, fournissent suffisamment d’arginine. Cependant en cas d’alimentation modérée, des suppléments d’arginine sont susceptibles d’accroître la rétention azotée. En outre, l’amélioration de l’état nutritionnel permise par l’arginine supplémentaire en phase post-traumatique montre une augmentation importante du besoin dans cette situation de stress, ainsi qu’une implication de cette molécule dans les processus d’accrétion tissulaire. Les différentes voies du métabolisme de l’arginine conduisent à des composés tels que l’ornithine, la proline, le glutamate, les polyamines et le NO, dont le potentiel d’action au niveau cellulaire est considérable. Ils sont susceptibles de produire de nombreux effets biologiques et d’expliquer en partie les multiples activités physiologiques autres que nutritionnelles de l’arginine.

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Audu, R., A. B. Amin, M. S. Sadiq, A. Tijjani, L. Babangida, and I. Abdullahi. "Chemical Composition of African Black Plum (Vitex Doniana) Leaf Ensiled with Urea and Broiler Litter." Nigerian Journal of Animal Production 49, no. 4 (February 10, 2023): 145–53. http://dx.doi.org/10.51791/njap.v49i4.3711.

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Inadequacy of feed resources as well as their low nutritional quality especially during the dry season subject animals to nutritional stress. The nutritive value of feed resources can be improved for enhanced utilization by rumen microbes for optimum growth by treating with non-protein nitrogen sources. Conservation of grasses and other herbage to minimize loss in their nutrient composition can be achieved through ensilage. The experiment was conducted to evaluate the nutritional potential of African black plum (Vitex doniana) leaf ensiled with broiler litter and urea. Four silages were prepared in which African Black Plum Leaf (ABPL) were ensiled alone (T1 ; control), with 1% urea (T2 ), 25% broiler litter (T3 ) and 25% broiler litter + 1% urea (T4 ) and replicated three times in bamma bottles for a period of 21 days. Physical properties, proximate and mineral composition of the silages were evaluated. Results of the physical properties of the silages showed that the silages were light brown for T1 and T2 and yellowish green for T 3 and T 4 . The aroma and texture were pleasant and firm for T1 and T2 while T3 and T4 had very sweet aroma with a firm texture. The values obtained for pH and temperature ranged from 6.50 – 7.87 and 28.17 – 29.60o C, respectively. Proximate and mineral composition showed significant (p<0.05) differences in the silages obtained. T3 (25% broiler litter) had the highest CP content (17.32 %) while T (25% broiler litter + 1% 4 urea) showed higher values for EE and NFE (3.70 % and 56.19 %, respectively). Sodium, potassium and magnesium were significantly (p<0.05) higher in T (0.61%, 1.72% and 2 0.83%, respectively)whereas T had higher content of iron and copper (80.4 mg/kg and 12.5 3 mg/kg, respectively). It could be concluded that the silages possessed good physical properties and appreciable proximate and mineral composition and thus, could be a potential feed resource that could be used to supplement animal feeds during periods of feed scarcity. Insuffisance des ressources alimentaires ainsi que leur faible qualité nutritionnelle, en particulier pendant la saison sèche, les animaux soumettent des animaux au stress nutritionnel. La valeur nutritive des ressources alimentaires peut être améliorée pour une utilisation améliorée par les microbes du rumen pour une croissance optimale en traitant avec des sources d'azote non protéiques. La conservation des graminées et d'autres herbages pour minimiser la perte de leur composition en nutriments peut être obtenue par l'écrivain.mL'expérience a été menée pour évaluer le potentiel nutritionnel de la feuille noire africaine (Vitex doniana) avec une litière de poulet et de l'urée. Quatre silages ont été préparés dans lesquels la feuille de prune noire africaine (FPNA) a été inscrite seule (T ; contrôle), avec 1%d'urée (T ), 25% de litière de poulet (T ) et 25% de litière de poulet + 1% d'urée (T ) et 2 3 4 reproduit trois fois dans des bouteilles de bamma pendant une période de 21 jours. Les propriétés physiques, la composition immédiate et minérale des silages ont été évaluées. Les résultats des propriétés physiques des silages ont montré que les silages étaient brun clair pour T1 et T2 et vert jaunâtre pour T3 et T4 . L'arôme et la texture étaient agréables et fermes pour T1 et T2 tandis que T3 et T4 avaient un arôme très doux avec une texture ferme. Les valeurs obtenues pour le pH et la température variaient de 6,50 à 7,87 et 28,17 à 29,600 ° C, respectivement. La composition immédiate et minérale a montré des différences significatives (p <0,05) dans les silages obtenus. T (25% de litière de poulet) avait la teneur 3 en CP la plus élevée (17,32%) tandis que T (25% de litière de poulet + 1% d'urée) a montré 4 des valeurs plus élevées pour EE et NFE (3,70% et 56,19%, respectivement). Le sodium, le potassium et le magnésium étaient significativement (P <0,05) plus élevés en T (0,61%, 2 1,72% et 0,83%, respectivement) tandis que T avait une teneur plus élevée en fer et en cuivre 3 (80,4 mg / kg et 12,5 mg / kg, respectivement). On pourrait conclure que les silages possédaient de bonnes propriétés physiques et une composition immédiate et minérale appréciable et pourraient donc être une ressource d'alimentation potentielle qui pourrait être utilisée pour compléter les aliments pour animaux pendant les périodes de rareté d'alimentation.

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Dissertations / Theses on the topic "Stress nutritionnel"

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Martin, Jessica. "Les effets interactifs du stress et de la diète sur la prise alimentaire et l'activité neuronale." Thesis, Université Laval, 2011. http://www.theses.ulaval.ca/2011/28025/28025.pdf.

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Frifra, Mehdi. "Impact des Nutriments sur les Maladies Métaboliques : caractérisation d'échantillons végétaux sur des modèles cellulaires impliqués dans l’obésité." Thesis, Angers, 2017. http://www.theses.fr/2017ANGE0084.

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L’obésité est la pathologie métabolique la plus répandue dans le monde, induisant le développement de maladies telles que la stéatose hépatique non-alcoolique et l’athérosclérose. L’approche nutritionnelle apparaît primordiale dans la prévention de ces désordres métaboliques. Des études ont démontré une relation inverse entre la consommation de végétaux et le développement de maladies métaboliques. L’objectif de cette étude est d’évaluer l’impact des conditions de culture et de conservation couplé à la variabilité génétique de deux végétaux (pommes et carottes) sur des modèles cellulaires dont la fonction est altérée lors de l’obésité (hépatocytes et adipocytes). Quatre variétés de pommes (Gala, Golden Delicious, Granny Smith et Pink Lady) ont été stockées selon quatre modes de conservation tandis que six variétés de carottes (Karotan, Bolero, Presto, Deep Purple, Kintoki et Blanche des Vosges) ont été cultivées selon quatre méthodes différentes. La stratégie de ce projet consiste en une mise en place de protocoles adéquats pour le criblage cellulaire dans différents processus métaboliques tels que l’apoptose, l’accumulation des lipides et le stress oxydant. Le criblage cellulaire a démontré une variabilité des effets des échantillons dépendant de la conservation, de la culture et de la variabilité génétique. Ces résultats ont permis de les classer en fonction de leurs effets bénéfiques. Les deux échantillons de pommes ayant le plus haut potentiel anti-apoptotique sur les cellules endothéliales ont été choisis afin de déterminer leurs mécanismes d’actions. Les résultats montrent que le mécanisme d’action de ces échantillons met en jeu la modulation du stress oxydant
Obesity is a metabolic disorder that is spreading worldwide. Obesity can lead to many diseases such as non-alcoholic fatty liver disease or atherosclerosis. Nutritional approach appears to be an essential strategy for the prevention of metabolic disorders. Indeed, some studies show the correlation between vegetables’ consumption and decrease of cardiovascular diseases.The aim of the study is to evaluate the impact of harvests and storages’ conditions coupled with genetic variability of two vegetables (apples and carrots) on cellular models in which their function is altered during obesity (hepatocytes and adipocytes). Four varieties of apple (Gala, Golden Delicious, Granny Smith and Pink Lady) have been used depending on four different types of storage whereas six varieties of carrots (Karotan, Bolero, Presto, Deep Purple, Kintoki and Blanche des Vosges) have been harvested in four different ways.The strategy of this project is to put some proper protocols for cellular screening in different metabolic processes such as apoptosis, adipocyte differentiation, lipid accumulation, and oxidative stress. Cellulars creening showed variabilities on samples effects depending on storage and harvest conditions, and genetic variabilities. These results allowed us to classify samples according to their most interesting beneficial effects. Then, we chose apple samples with the highest anti-apoptotic effects on endothelial cells in order to investigate their mechanisms of action. The results show that the ability of apple samples to reduce apoptosis is associated with the modulation of oxidative stress

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Walter, Allison. "Propriétés anti-angiogéniques des polyphénols du vin rouge in vivo : rôle potentiel dans la prévention de l'athérosclérose et des cancers." Strasbourg, 2009. http://www.theses.fr/2009STRA6268.

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En 2005 l’Organisation Mondiale de la Santé (OMS) décomptait 58 millions de décès dans le monde dont 30% étaient dus aux maladies cardiovasculaires et 13% aux cancers, pathologies dont le développement est en partie contrôlé par la néo-angiogenèse. Des études épidémiologiques ont montré qu’une consommation régulière de fruits et de légumes et de vin rouge, en quantité modérée, est associée à une réduction du risque d’apparition de maladies cardiovasculaires et de cancers. Cet effet protecteur a été attribué en partie aux composés polyphénoliques. L’objectif principal de ce travail est d’évaluer le potentiel anti-angiogénique des polyphénols du vin rouge in vivo et de déterminer si ces propriétés contribuent à retarder la croissance tumorale et le développement de pathologies cardiovasculaires. Une première étude a permis de montrer que l’absorption de polyphénols du vin rouge prévient le stress oxydant ainsi que l’expression des ces facteurs pro-angiogéniques induits par l’angiotensine II in vivo. Une seconde étude a démontré que l’effet pro-angiogénique de l’angiotensine II est associé à la formation de néo-vaisseaux et à l’expression de facteurs pro-angiogéniques et que l’effet anti-angiogénique des polyphénols de vin rouge est associé à la prévention de cette néoangiogenèse induite par l’angiotensine ainsi qu’à une prévention de l’expression des facteurs pro-angiogéniques. Un modèle de tumeurs colorectales sous-cutanées a permis de démontrer que l’absorption de polyphénols in vivo permet de prévenir la croissance tumorale associée à une réduction de l’angiogenèse, de l’expression de facteurs pro-angiogénqiues tout en induisant l’expression de gènes suppresseurs de tumeurs
In 2005 the World Health Organization (WHO) mentioned 58 millions of death among them 30% are attributated to cadiovascular disease and 13% to cancers, pathologies associated to angiogenesis. Epidemiological studies demonstrated that a regular intake of fruits, vegetables and red wine is associated to a reduced risk of ardiovascular diseases and cancers. This protective effect has been attributed to polyphenolic compounds. The major goal of this study is to evaluate the in vivo anti-angiogenic potential of red wine polyphenols and to determine if these properties participate the prevention of cardiovascular diseases and tumoral development. A first study demonstrated that in vivo intake of red wine polyphenols prevent oxidative stress and pro-angiogenic factors induced by angiotensin II. A second one, demonstrated that the pro-angiogenic effect of angiotensine II is associated to the development of new blood vessels and to pro-angiogenic factors. Red wine polyphenols intake prevent new blood vessels formation as weel as pro-angiogenic factors expression. A sub-cutanous colorectal cancer model, let us to show that red wine polyhenols intake in vivo, reduces tumor development, neo-angiogenesis, tumor pro-angiogenic factors and induces apoptosis

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Dragin, Nadine Aude. "Implication des facteurs nutritionnels et du stress oxydant dans la régulation de l'expression génique au cours du vieillissement chez la souris." Bordeaux 2, 2003. http://www.theses.fr/2003BOR21041.

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Le stress oxydant (SO) est impliqué dans le processus du vieillissement. Pour comprendre le rôle des facteurs nutritionnels sur le SO, nous étudions l'effet d'une alimentation standard, restrictive (RC), cafeteria (CD) et d'un SO chronique par le paraquat (PQ) sur des souris mâles C57BL6J au cours du vieillissement. Le statut antioxydant (SOD, GPX, Catalase et vitamines E, A) est estimé dans le sang, le foie et le cerveau. L'expression génique est suivie par cDNA array. Les performances cognitives sont évaluées par des tests comportementaux de mémoire. PQ et CD accélèrent la diminution liée à l'âge du SA et favorisent l'expression de gènes impliqués dans la prolifération et la différenciation cellulaire dans les différents tissus. Par contre, RC réprime la décroissance du SA et stimule l'expression des gènes de réparation et de renouvellement cellulaire. La diminution liée à l'âge des capacités d'apprentissage est augmentée par CD et PQ mais réprimée par RC comparé au témoin. Ces résultats montrent que l'interrelation entre le SO, le vieillissement tissulaire et cognitif qui peut être modulé par des facteurs nutritionnels
There is some evidence that diet and oxidative stress can modulate the ageing process. To assess the role of nutritional factors on oxidative stress in liver and brain during ageing, we separated mice C57BL6j male in 4 groups : a standard, restriction (RD) and cafeteria (CD) diets, a chronic oxidative stress by Paraquat (PQ). Blood, liver and brain antioxidant status (AS) was determined by vitamins A, E, superoxyde dismutase, gluthation peroxydase and catalase analysis. Gene expression was studied by using cDNA arrays. Cognitive performances were evaluated using behavioral tests. PQ and CD enhanced the effect of ageing on AS and learning capacity compared to controls. They activate expression of gene implicated in proliferation and differentiation in tissues. On contrary, RC decrease ageing effect on AS and acquisition capacity and increase expression of gene implicated in reparation and cell survival. These results suggested a relationship between OS, ageing tissue, cognitive performances that could be modified by nutritional factors

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Ruel, Guillaume. "Effets de la canneberge (Vaccinium Macrocarpon) sur le profil cardiométabolique chez l'homme: Lipides, stress oxydatif, inflammation et fonction endothéliale." Thesis, Université Laval, 2010. http://www.theses.ulaval.ca/2010/27454/27454.pdf.

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Le, Goffe Claire. "Contrôle métabolique de la réponse des cellules épithéliales au stress oxydatif : une nouvelle approche par manipulation de la source hydrocarbonée des cellules en culture." Paris 7, 2003. http://www.theses.fr/2003PA077065.

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Corbel, Hélène. "Envol chez le poussin d'oiseau : Rôle de l'investissement parental et mécanismes proximaux." Strasbourg 1, 2008. http://www.theses.fr/2008STR13220.

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L’envol du jeune oiseau est une transition vers l’autonomie locomotrice et alimentaire. L’état physique doit alors être optimisé pour limiter les risques accrus de mortalité par prédation ou par famine. Cet état est largement dépendant de l’investissement parental lequel fait l’objet d’un conflit entre parents et petits. Mon travail de thèse s’attache à comprendre les mécanismes proximaux retenus chez l’oiseau pour optimiser le phénotype à l’envol. Deux espèces à l’écologie contrastée ont été comparées: le Manchot royal (MR; Aptenodytes patagonicus) et la Cigogne blanche (CB; Ciconia ciconia). Chez le MR, l’accumulation de réserves lipidiques dans la progéniture permet à l’éleveur de déserter et d’initier la mue prénuptiale tout en assurant la fin de la croissance du poussin à jeun. De plus, ces réserves préviennent une activation de l’axe hypothalamo-hypophyso-corticosurrénalien (HHCS) et un catabolisme exacerbé des protéines, lequel menacerait l’intégrité musculaire du poussin. Chez la CB, la restriction alimentaire parentale induit chez les cigogneaux un stress nutritionnel qui active l’axe HHCS et la sécrétion de corticostérone. La corticostéronémie élevée stimulerait les exercices locomoteurs au nid et par là faciliterait l’envol. La hiérarchie de développement au sein de la nichée modulerait la sensibilité de l’axe HHCS, ce qui préviendrait les effets délétères d’une corticostéronémie chroniquement élevée sur la croissance alaire des derniers éclos. Mes résultats permettent de proposer de nouvelles hypothèses quant aux pressions sélectives exercées sur 1) l’accumulation des réserves lipidiques et 2) la sécrétion de corticostérone chez le poussin en fin de croissance
Fledging in birds is a transition from a situation in which it is totally dependent on its parents to a self-sufficient life. Physical state should be optimized at fledging to face increased predation and starvation risks outside the nest. Physical state at fledging is largely dependent on parental investment, over which parents and offspring disagree. My Ph. D work aims at understanding the proximate mechanisms that optimize phenotype at fledging. I used a comparison between two avian species with markedly different ecology: the King penguin (KP, Aptenodytes patagonicus) and the White stork (WS; Ciconia ciconia). In KP, parents accumulate important lipid stores in chicks before deserting and starting prenuptial moult. Lipid stores in deserted, fasting chicks fuel the completion of growth. Lipid stores also prevent the activation of the Hypothalamic-Pituitary-Adrenal (HPA) axis and associated increased catabolism of muscular proteins in chicks. In WS, parental food restriction results in a nutritional stress which activates the HPA axis and corticosterone release in chicks. High plasma levels of corticosterone stimulate flight-training activity and hence facilitate fledging. The down-regulation of the HPA axis in last-hatched chicks prevents the impairment of wing growth due to chronically elevated plasma levels of corticosterone. The results of my work are discussed and shed new light on the evolutionary forces that shape 1) fattening and 2) corticosterone release in prefledging birds

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Gagné, Amélie. "Étude des concentrations d'antioxydants plasmatiques après supplémentation en vitamines E et C au cours de la grossesse." Thesis, Université Laval, 2009. http://www.theses.ulaval.ca/2009/25990/25990.pdf.

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La prééclampsie (PE) est caractérisée par de l’hypertension et de la protéinurie maternelle survenant durant la grossesse. Certaines études ont suggéré que la supplémentation en vitamines (E et C) pourrait diminuer l’incidence de PE. Des échantillons sanguins de femmes avec (n=15) ou sans (n=100) PE, participant à l’étude International Trial of Antioxidants for the Prevention of PE (INTAPP), ont été collectés avant la prise de vitamines, ainsi qu’aux semaines 24 et 32 de la grossesse. Les niveaux de vitames ont été mesurés par HPLC. L’augmentation significative des niveaux d’α-tocophérol et de coenzyme Q10 au cours de la grossesse chez les femmes non supplémentées, avec ou sans PE, pourrait représenter une réponse naturelle effective contre le stress oxydatif. Le ratio abaissé de γ-/α-tocophérol, observé pour la première fois chez des femmes enceintes supplémentées, suggère une augmentation d’α-tocophérol et/ou une diminution de γ-tocophérol causée par une compétition pour l’absorption intestinale des tocophérols.
Preeclampsia (PE) is a syndrome characterized by hypertension and maternal proteinuria during pregnancy. Some studies have suggested that supplementation with vitamins (E and C) could decrease the incidence of PE. Women (n=100) from the International Trial of Antioxidants for the Prevention of PE study were collected at week 12-16 of gestation (prior to vitamins supplementation), then at weeks 24 and 32 of gestation. A second group of 15 preeclamptic women was also selected for this study. Vitamins were determined using high-performance liquid chromatography. The higher α-tocopherol and coenzyme Q10 concentrations during pregnancy in non-supplemented women, with or without PE, could represent a naturally response against oxidative stress in pregnant women. The lower ratio of γ-/α-tocopherol, observed for the first time in supplemented pregnant women, suggest an increase in plasma α-tocopherol due to dietary supplementation and/or a decrease in γ-tocopherol resulting from a competition for the intestinal absorption of tocopherols.

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Corblin, Fabien. "Conception et mise en oeuvre d'un outil déclaratif pour l'analyse des réseaux génétiques discrets." Phd thesis, Grenoble 1, 2008. https://theses.hal.science/tel-00388776.

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Une demande croissante d'outils pour construire et décrypter des réseaux génétiques contrôlant des processus cellulaires est ressentie en biologie. Nous soutenons que l'utilisation de l'approche déclarative est pertinente et applicable pour répondre aux questions des biologistes sur ces réseaux, en général partiellement connus. L'idée principale est de modéliser des connaissances portant à la fois sur la structure et la dynamique d'un réseau par un ensemble de contraintes représentant l'ensemble des solutions, de vérifier sa cohérence, de réparer une incohérence éventuelle par un relâchement automatique, et d'inférer des propriétés sur la structure et la dynamique du réseau. Pour montrer la faisabilité de l'approche, nous formalisons les réseaux discrets de R. Thomas et les propriétés biologiques pertinentes, proposons un outil reposant sur la programmation logique par contraintes en coopération avec un solveur SAT, et la validons sur des applications biologiques significatives
A growing demand for tools to build and decrypt genetic networks that control cellular processes is felt in biology. We argue that the use of the declarative approach is relevant and applicable to answer questions from biologists about these networks, which are in general partially known. The main idea is to model knowledge about both the structure and the dynamic of a network by a set of constraints representing all the solutions, to check its consistency, to repair a possible inconsistency by an automatic constraint removal, and to infer properties on the structure and dynamic of the network. To demonstrate the feasibility of the approach, we formalize the discrete networks of R. Thomas and relevant biological properties, offer a tool based on constraint logic programming in cooperation with a SAT solver, and validate it on significant biological applications

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Bourgoin, Frédéric. "La contribution du stress oxydatif et de médiateurs inflammatoires dans les complications vasculaires, métaboliques et moléculaires induites chez le rat soumis à une alimentation riche en gras et en sucre, un modèle de résistance à l'insuline." Thesis, Université Laval, 2012. http://www.theses.ulaval.ca/2012/29180/29180.pdf.

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L’obésité viscérale est identifiée comme étant le facteur de risque de maladies cardiovasculaires le plus contributif à la résistance à l’insuline. De mauvaises habitudes alimentaires et la sédentarité contribueraient à l’obésité et affecteraient de manière indépendante et défavorable les actions métaboliques et vasculaires de l’insuline. L’objectif visé par ce projet de recherche consistait à déterminer l’impact d’une alimentation riche en gras saturé et en sucre (HFHS) sur la fonction endothéliale ainsi que l’établissement d’un stress oxydatif et d’une réponse inflammatoire dans un modèle animal de résistance à l’insuline avec surplus de poids. Plus précisément, le chapitre 2 avait pour but de développer et de caractériser un nouveau modèle expérimental animal, le rat nourri avec un régime HFHS, plus représentatif de la diète consommée par un pourcentage élevé de la population nord-américaine. Le chapitre 3 avait pour objectif de déterminer les effets d’un traitement préventif avec un antioxydant, le tempol, sur la fonction endothéliale ainsi que les actions glucorégulatrices et hémodynamiques de l’insuline dans ce modèle animal. Le chapitre 4 avait pour but d’étudier les effets du régime HFHS et du tempol sur l’expression et l’activité de marqueurs des voies de signalisation de l’insuline ainsi que de biomarqueurs du stress oxydatif et de l’inflammation. Nous avons noté que le régime HFHS entraînait une altération de la vasodilatation endothélium-dépendante, une diminution du transport du glucose stimulé par l’insuline et de la sensibilité à l’insuline ainsi qu’une réduction de l’expression et de l’activation de plusieurs protéines de la voie de signalisation à l’insuline. Nous avons également identifié des facteurs du stress oxydatif ou inflammatoires susceptibles de contribuer à la dégradation de la fonction endothéliale et prendre part aux complications vasculaires et métaboliques induites par le régime HFHS chez le rat. Nous démontrons que plusieurs de ces altérations pouvaient être évitées, atténuées ou retardées par une intervention précoce destinée à contrôler le stress oxydatif. Ce projet de recherche a permis de mieux comprendre l’implication et le lien entre le NO endothélial et le stress oxydatif ainsi que l’inflammation induits par un régime HFHS, dans un modèle animal de résistance à l’insuline avec surplus de poids.
Visceral obesity has been identified as the main cardiovascular disease risk factor that contributes to insulin resistance. Bad eating habits and sedentary lifestyle can contribute to obesity, but can also affect independently and unfavourably the metabolic and vascular insulin actions. The aim of this research project was to determine the impact of a high fat high sucrose diet (HFHS) on endothelial function as well as the establishment of an oxidative stress and inflammatory response in an animal model of dietary-acquired insulin resistance and obesity. Precisely, the objective of chapter 2 was to develop a new animal experimental model, the rat fed with a diet rich in saturated fat and refined sugar, representative of the high-energy diets frequently consumed by a large percentage of North American. The aim of chapter 3 was to determine the effects of a preventive treatment with an antioxidant, tempol, on endothelial function as well as glucoregulatory and hemodynamic actions of insulin in this animal model. The objective of chapter 4 was to study the effects of HFHS diet and tempol on the expression and activity of markers of insulin signalling pathways, oxidative stress and inflammation. We noted that the HFHS diet altered the endothelium-dependent vasodilation, decreased insulin-stimulated glucose transport and insulin sensitivity as well as reduced expression and activation of many insulin signalling pathway proteins. We also identified oxidative stress or inflammatory markers that could contribute to endothelial function degradation and take part in vascular and metabolic complications induced by the HFHS diet, in the rat. We demonstrated that many of those alterations could be avoided, attenuated or prevented by an early intervention aimed at controlling oxidative stress. This research project provided a better understanding of the implication and the link between endothelial NO and the oxidative stress as well as the inflammation induced by a HFHS diet, in an animal model of diet-induced insulin resistance and obesity.

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Books on the topic "Stress nutritionnel"

1

Donsbach, Kurt W. Stress. Sherbrooke, Québec: Éditions du IIIe millénaire, 1990.

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Physical exercise, nutrition, and stress. New York: Praeger, 1985.

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Asterita, Mary F. Physical exercise, nutrition, and stress. New York: Praeger, 1986.

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Swarth, Judith. Nutrition for stress. Edited by HealthMedia Editorial Panel. London: Foulsham, 1992.

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Swarth, Judith. Nutrition for stress. Edited by Health Media Editorial Panel. Slough: Foulsham, 1992.

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Swarth, Judith. Stress and nutrition. San Diego, CA: Health Media of America, 1986.

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The psychology of stress & nutrition. Portland, Or: National Book Co., 1991.

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1921-, Kinney John M., Tucker Hugh N, and Clintec International Horizons Conference (3rd : 1996 : Amsterdam, Netherlands), eds. Physiology, stress, and malnutrition: Functional correlates, nutritional intervention. Philadelphia: Lippincott-Raven, 1997.

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Jun, Liu, ed. Ying yang jian ya: Shi wu jian ya he xiang shou sheng huo de fang fa. Beijing: Zhongguo qing gong ye chu ban she, 2004.

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Nam, Ki-hong. Sŭtʻŭresŭ irŏkʻe pʻunda: Sŭtʻŭresŭ haeso wa kŏnʼganghan sam ŭi iyagi. Sŏul: Ilsŏn Kihoek, 1990.

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Book chapters on the topic "Stress nutritionnel"

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Henning, Susanne. "Oxidant Stress and Carcinogenesis." In Nutritional Oncology, 157–76. Boca Raton: CRC Press, 2021. http://dx.doi.org/10.1201/9780429317385-8.

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Mahmoud, Iman F., Omar A. Alhaj, and Haitham A. Jahrami. "The Interplay between Iron and Oxidative Stress in Brain Neurodegenerative Diseases." In Nutritional Neurosciences, 23–43. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-7327-7_2.

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Hassan, Sarah, Mario Eid, Ahmad Hassan, and Samer El Hayek. "Blood Markers of Oxidative Stress in Patients with Amyotrophic Lateral Sclerosis." In Nutritional Neurosciences, 155–68. Singapore: Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-99-1513-2_8.

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Minagawa, Sakiko, and Jackie Buell. "Nutritional Optimization for Athletes with Stress Fractures." In Stress Fractures in Athletes, 129–39. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-46919-1_9.

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Mehta, Sahil, Mansi Gogna, Baljinder Singh, Anupam Patra, Indrakant Kumar Singh, and Archana Singh. "Silicon: A Plant Nutritional “Non-Entity” for Mitigating Abiotic Stresses." In Plant Stress Biology, 17–49. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-9380-2_2.

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Bertolazi, Amanda Azevedo, Muriel da Silva Folli-Pereira, Gustavo Caione, Lucas Zanchetta Passamani, Carlos Moacir Colodete, Sávio Bastos de Souza, Alessandro Coutinho Ramos, Nazima Rasool, Getúlio de Freitas Seben Júnior, and Evandro Luiz Schoninger. "Linking Plant Nutritional Status to Plant-AMF Interactions." In Plant Microbiome: Stress Response, 351–84. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-10-5514-0_16.

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Sole, Michael J. "Conditioned Nutritional Requirements of the Failing Heart." In Nutrients, Stress, and Medical Disorders, 341–52. Totowa, NJ: Humana Press, 2006. http://dx.doi.org/10.1385/1-59259-952-4:341.

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Heer, Martina, Natalie Baecker, Scott M. Smith, and Sara R. Zwart. "Nutritional Countermeasures for Spaceflight-Related Stress." In Stress Challenges and Immunity in Space, 593–616. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-16996-1_33.

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Heer, Martina, Natalie Baecker, Scott M. Smith, and Sara R. Swart. "Nutritional Countermeasures for Spaceflight-Related Stress." In Stress Challenges and Immunity in Space, 387–403. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-22272-6_29.

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Dhawan, Vibha. "Sustainable Agriculture Practices for Food and Nutritional Security." In Plant Acclimation to Environmental Stress, 343–57. New York, NY: Springer New York, 2012. http://dx.doi.org/10.1007/978-1-4614-5001-6_13.

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Conference papers on the topic "Stress nutritionnel"

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Nieman, David. "A Multi-Omics Approach to Interpreting the Influence of Polyphenols in Countering Exercise-Induced Physiological Stress." In The 1st International Electronic Conference on Nutrients - Nutritional and Microbiota Effects on Chronic Disease. Basel, Switzerland: MDPI, 2020. http://dx.doi.org/10.3390/iecn2020-06978.

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Dolezal, Adam. "Effects of larval nutritional stress on honey bee disease susceptibility and immunocompetence." In 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.112115.

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Feun, Lynn G., Chunjing Wu, Ying-Ying Li, Min You, Medhi Wangpaichitr, Miguel Suarez, and Niramol G. Savaraj. "Abstract 2336: Eradicating melanoma cells using combination of nutritional stress and checkpoint inhibitors." In Proceedings: AACR Annual Meeting 2021; April 10-15, 2021 and May 17-21, 2021; Philadelphia, PA. American Association for Cancer Research, 2021. http://dx.doi.org/10.1158/1538-7445.am2021-2336.

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Ferreira, Eliz Garcia, Jamille Karolyne da Conceição, and Ana Paula de Mello. "Nutritional risk patients management in a stroke reference center." In XIII Congresso Paulista de Neurologia. Zeppelini Editorial e Comunicação, 2021. http://dx.doi.org/10.5327/1516-3180.328.

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Introduction: Nutritional screening should be used as a tool nutritional risk early identification, aiming at intervention for the prevention of malnutrition and rehabilitation. Objectives: Report nutritional risk management protocol in patients admitted for suspected stroke. Methodology: Experience report on the working method of nutrition team at a stroke reference center. Results: Nutrition screening by a Dietist is applied within 72 hours of admission of all patients admitted to the acute/integral stroke unit. First, NRS-2002 tool is applied, in which the following items are considered: BMI < 20.5Kg/m²; weight loss in the past three months; reduction in food intake in the last week; metabolic stress and age (≥70 years old). Those with a speech-language diagnosis of dysphagia are also considered at nutritional risk. After, anthropometric measurements: weight and height are measured with walking patients, or knee height, brachial and calf circumference of those with cognitive and/or motor disabilities. Individualized nutritional therapy (oral/enteral) is prescribed. In addition, cases are discussed in a multiprofessional daily round to define actions during rehabilitation and in the discharge process (conter- referral to primary care, nutrition advice and continuity of nutritional therapy at home). Conclusions: Establishing a nutritional risk management protocol is important for early identification in post-stroke patients, since nutritional status is directly related to a good prognosis and long-term quality of life.

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Hurtado, F. Montenegro, A. Reyes Trujillo, C. A. Galíndez Jamioy, and E. Solarte Rodriguez. "Application of optical methods to diagnose nutritional stress on Tabasco Pepper (Capsicum frutescens) Crops." In Latin America Optics and Photonics Conference. Washington, D.C.: OSA, 2018. http://dx.doi.org/10.1364/laop.2018.tu4a.8.

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Toyomizu, M., A. Mujahid, R. Hirakawa, K. Furukawa, M. A. K. Azad, M. Taciak, and M. Kikusato. "Nutritional regulation of mitochondrial ROS production of chickens exposed to acute and chronic heat stress." In 6th EAAP International Symposium on Energy and Protein Metabolism and Nutrition. The Netherlands: Wageningen Academic Publishers, 2019. http://dx.doi.org/10.3920/978-90-8686-891-9_5.

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Cupp, M., Ed Haworth, A. Costello, L. Manikam, D. Manandhar, H. Kuper, and M. Heys. "121 Assessing nutritional and educational inclusion status of nepali children screening positive for disability and variation of prevalence at different thresholds of disability screening definition." In Great Ormond Street Hospital Conference 2018: Continuous Care. BMJ Publishing Group Ltd and Royal College of Paediatrics and Child Health, 2018. http://dx.doi.org/10.1136/goshabs.121.

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Kurcubic, Vladimir, Slavisa Stajic, and Nemanja Miletic. "UTICAJ ODREĐENIH STRESOGENIH FAKTORA NA KVALITET GOVEĐEG MESA." In XXVI savetovanje o biotehnologiji sa međunarodnim učešćem. University of Kragujevac, Faculty of Agronomy, 2021. http://dx.doi.org/10.46793/sbt26.473k.

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Stress inevitably occurs from farm to slaughter in modern cattle breeding. The effects of stress on behavior, physiological status, and meat quality have been examined by a number of authors. The mechanism of the effects of stress on physiological and biochemical changes and the consequent effects on meat quality attributes are significantly more limited. This review summarizes the primary stress factors that affect animal welfare and cause biochemical changes during the early postmortem period, which reduces the quality of carcasses and their nutritional quality. In order to obtain high quality meat, further studies are needed to uncover the complex mechanisms mentioned above.

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Prakasam, Gopinath, and Rameshwar N. K. Bamezai. "Abstract B19: LKB1-AMPK axis regulates the switch of Pyruvate Kinase M isoforms to tolerate nutritional stress." In Abstracts: AACR Special Conference: Metabolism and Cancer; June 7-10, 2015; Bellevue, WA. American Association for Cancer Research, 2016. http://dx.doi.org/10.1158/1557-3125.metca15-b19.

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Nurahmawati, Dhewi, Harsono Salimo, and Yulia Lanti Retno Dewi. "EFFECTS OF MATERNAL EDUCATION, PSYCHOSOCIAL STRESS, NUTRITIONAL STATUS AT PREGNANCY, AND FAMILY INCOME, ON BIRTHWEIGHT IN NGANJUK, EAST JAVA." In THE 2ND INTERNATIONAL CONFERENCE ON PUBLIC HEALTH. Masters Program in Public Health, Graduate School, Sebelas Maret University Jl. Ir Sutami 36A, Surakarta 57126. Telp/Fax: (0271) 632 450 ext.208 First website:http//: pasca.uns.ac.id/s2ikm Second website: www.theicph.com. Email: theicph2017@gmail.com, 2017. http://dx.doi.org/10.26911/theicph.2017.110.

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Reports on the topic "Stress nutritionnel"

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Van Benthem, Mark Hilary, Ryan W. Davis, James Bryce Ricken, Amy Jo Powell, and Michael Robert Keenan. Hyperspectral imaging of oil producing microalgae under thermal and nutritional stress. Office of Scientific and Technical Information (OSTI), September 2008. http://dx.doi.org/10.2172/946556.

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Wolfenson, David, William W. Thatcher, Rina Meidan, Charles R. Staples, and Israel Flamenbaum. Hormonal and Nutritional Stretegies to Optimize Reproductive Function and Improve Fertility of Dairy Cattle during Heat Stress in Summer. United States Department of Agriculture, August 1994. http://dx.doi.org/10.32747/1994.7568773.bard.

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The BARD program includes two main parts. In the first, experiments were conducted to complete our understanding of the mechanisms responsible for the impairment of reproductive functions under heat stress. Experiments focused on follicular development and function, since results obtained in our previous BARD project indicate that the preovulatory follicle is susceptible to heat stress. The theca cells, sensitive to thermal stress, produced less androgen during the summer, as well as during the autumn. Similarly, luteinized theca cells obtained from cows in summer produced much less progesterone than in winter. Granulosa cells and luteinized granulosa cells were less susceptible to heat stress. A delayed effect of heat stress on follicular development, on suppression of dominance and on steroid production by theca and granulosa cells was noted. This may be related to the low fertility of cows during the cool months of autumn. In the second part, experiments were conducted aiming to improve fertility in summer. The timed AI program was developed using two injections of GnRH coupled with PGF2a. It was found effective in improving reproductive performance in lactating cows. Limitations induced by heat stress on estrus detection were eliminated with the timed AI management program. Replacing the second injection of GnRH with hCG instead of GnRH agonist increased plasma progesterone levels post ovulation but did not improve fertility. Use of the timed AI program in summer, shortened days open and increased the net revenue per cow, however, it did not protect the embryo fiom temperature-induced embryonic mortality. Incorporation of a GnRH-agonist implant into the timed AJ program was examined. The implant increased plasma progesterone and LH concentrations and altered follicular dynamics. The use of a GnRH-implant enhanced pregnancy rate in cows with low body conditions. In a timed embryo transfer experiment, the use of fresh or frozen in vitro produced embryos was compared in the summer to improve fertility. The use of flesh embryos (but not frozen ones) improved pregnancy rate, however, substantial embryonic death occurred between 21 and 45 days. The timed AI program, which is now being used commercially, shortened days open, and increased pregnancy rate during summer. Other approaches which were found to improve fertility in small-scale studies, need to be tested again in large-scale field trials.

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Ibdah, Mwafaq, Dorothea Tholl, and Philipp W. Simon. How temperature stress changes carrot flavor: Elucidating the genetic determinants of undesired taste in carrots. United States Department of Agriculture, January 2014. http://dx.doi.org/10.32747/2014.7598171.bard.

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Global climate change and warming temperatures represent the greatest future challenge for global food production and quality. In this project, we will define the genetic factors of climate-associated taste deficiencies in carrot. Carrot is considered one of the leading horticultural crops in the world in terms of its nutritional value, health benefits, and unique flavor based on its high content of carotenoids and volatile aroma compounds. In recent years, carrot genotypes of different color with improved nutraceutical attributes have been developed. When exposed to high growth temperatures, carrots develop an undesired harsh and bitter taste caused by the accumulation of terpene metabolites. This taste deficiency represents a quality defect to carrot breeders and large- scale growers and needs to be minimized for successful marketing of carrot crops. Surprisingly, the genetic determinants of bitter and harsh flavor in carrot and their response to temperature stress are not well characterized. We started to elucidate these factors in different carrot cultivars by investigating the biosynthesis of volatile terpenes, which represent the predominant flavor compounds in carrots. Also, up to date we identified and characterized two terpenesynthase enzymes, one of which produces (E)-β- caryophyllene, a major terpene component in carrot root. Both TPSs may contribute to the observed variation in volatile terpene formation.

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Meiri, Noam, Michael D. Denbow, and Cynthia J. Denbow. Epigenetic Adaptation: The Regulatory Mechanisms of Hypothalamic Plasticity that Determine Stress-Response Set Point. United States Department of Agriculture, November 2013. http://dx.doi.org/10.32747/2013.7593396.bard.

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Our hypothesis was that postnatal stress exposure or sensory input alters brain activity, which induces acetylation and/or methylation on lysine residues of histone 3 and alters methylation levels in the promoter regions of stress-related genes, ultimately resulting in long-lasting changes in the stress-response set point. Therefore, the objectives of the proposal were: 1. To identify the levels of total histone 3 acetylation and different levels of methylation on lysine 9 and/or 14 during both heat and feed stress and challenge. 2. To evaluate the methylation and acetylation levels of histone 3 lysine 9 and/or 14 at the Bdnfpromoter during both heat and feed stress and challenge. 3. To evaluate the levels of the relevant methyltransferases and transmethylases during infliction of stress. 4. To identify the specific localization of the cells which respond to both specific histone modification and the enzyme involved by applying each of the stressors in the hypothalamus. 5. To evaluate the physiological effects of antisense knockdown of Ezh2 on the stress responses. 6. To measure the level of CpG methylation in the promoter region of BDNF in thermal treatments and free-fed, 12-hour fasted, and re-fed chicks during post-natal day 3, which is the critical period for feed-control establishment, and 10 days later to evaluate longterm effects. 7. The phenotypic effect of antisense “knock down” of the transmethylaseDNMT 3a. Background: The growing demand for improvements in poultry production requires an understanding of the mechanisms governing stress responses. Two of the major stressors affecting animal welfare and hence, the poultry industry in both the U.S. and Israel, are feed intake and thermal responses. Recently, it has been shown that the regulation of energy intake and expenditure, including feed intake and thermal regulation, resides in the hypothalamus and develops during a critical post-hatch period. However, little is known about the regulatory steps involved. The hypothesis to be tested in this proposal is that epigenetic changes in the hypothalamus during post-hatch early development determine the stress-response set point for both feed and thermal stressors. The ambitious goals that were set for this proposal were met. It was established that both stressors i.e. feed and thermal stress, can be manipulated during the critical period of development at day 3 to induce resilience to stress later in life. Specifically it was established that unfavorable nutritional conditions during early developmental periods or heat exposure influences subsequent adaptability to those same stressful conditions. Furthermore it was demonstrated that epigenetic marks on the promoter of genes involved in stress memory are altered both during stress, and as a result, later in life. Specifically it was demonstrated that fasting and heat had an effect on methylation and acetylation of histone 3 at various lysine residues in the hypothalamus during exposure to stress on day 3 and during stress challenge on day 10. Furthermore, the enzymes that perform these modifications are altered both during stress conditioning and challenge. Finally, these modifications are both necessary and sufficient, since antisense "knockdown" of these enzymes affects histone modifications, and as a consequence stress resilience. DNA methylation was also demonstrated at the promoters of genes involved in heat stress regulation and long-term resilience. It should be noted that the only goal that we did not meet because of technical reasons was No. 7. In conclusion: The outcome of this research may provide information for the improvement of stress responses in high yield poultry breeds using epigenetic adaptation approaches during critical periods in the course of early development in order to improve animal welfare even under suboptimum environmental conditions.

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Halevy, Orna, Sandra Velleman, and Shlomo Yahav. Early post-hatch thermal stress effects on broiler muscle development and performance. United States Department of Agriculture, January 2013. http://dx.doi.org/10.32747/2013.7597933.bard.

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In broilers, the immediate post-hatch handling period exposes chicks to cold or hot thermal stress, with potentially harmful consequences to product quantity and quality that could threaten poultry meat marketability as a healthy, low-fat food. This lower performance includes adverse effects on muscle growth and damage to muscle structure (e.g., less protein and more fat deposition). A leading candidate for mediating the effects of thermal stress on muscle growth and development is a unique group of skeletal muscle cells known as adult myoblasts (satellite cells). Satellite cells are multipotential stem cells that can be stimulated to follow other developmental pathways, especially adipogenesis in lieu of muscle formation. They are most active during the first week of age in broilers and have been shown to be sensitive to environmental conditions and nutritional status. The hypothesis of the present study was that immediate post-hatch thermal stress would harm broiler growth and performance. In particular, growth characteristics and gene expression of muscle progenitor cells (i.e., satellite cells) will be affected, leading to increased fat deposition, resulting in long-term changes in muscle structure and a reduction in meat yield. The in vitro studies on cultured satellite cells derived from different muscle, have demonstrated that, anaerobic pectoralis major satellite cells are more predisposed to adipogenic conversion and more sensitive during myogenic proliferation and differentiation than aerobic biceps femoris cells when challenged to both hot and cold thermal stress. These results corroborated the in vivo studies, establishing that chronic heat exposure of broiler chicks at their first two week of life leads to impaired myogenicity of the satellite cells, and increased fat deposition in the muscle. Moreover, chronic exposure of chicks to inaccurate temperature, in particular to heat vs. cold, during their early posthatch periods has long-term effects of BW, absolute muscle growth and muscle morphology and meat quality. The latter is manifested by higher lipid and collagen deposition and may lead to the white striping occurrence. The results of this study emphasize the high sensitivity of muscle progenitor cells in the early posthatch period at a time when they are highly active and therefore the importance of rearing broiler chicks under accurate ambient temperatures. From an agricultural point of view, this research clearly demonstrates the immediate and long-term adverse effects on broiler muscling and fat formation due to chronic exposure to hot stress vs. cold temperatures at early age posthatch. These findings will aid in developing management strategies to improve broiler performance in Israel and the USA. BARD Report - Project4592 Page 2 of 29

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Jander, Georg, Gad Galili, and Yair Shachar-Hill. Genetic, Genomic and Biochemical Analysis of Arabidopsis Threonine Aldolase and Associated Molecular and Metabolic Networks. United States Department of Agriculture, January 2010. http://dx.doi.org/10.32747/2010.7696546.bard.

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Since the amino acids threonine and isoleucine can be limiting in mammalian diet and there is interest in increasing their abundance in certain crop plants. To meet this need, a BARD proposal was written with two main research objectives: (i) investigate new avenues for manipulating threonine and isoleucine content in plants and (ii) study the role of threonine aldolase in plant metabolism. Research conducted to meet these goals included analysis of the sub-cellular localization of threonine aldolase in the plant, analysis of metabolic flux in developing embryos, over- and under-expression of Arabidopsis threonine aldolases, and transcriptional and metabolic analysis of perturbations resulting from altered threonine aldolase expression. Additionally, the broader metabolic effects of increasing lysine biosynthesis were investigated. An interesting observation that came up in the course of the project is that threonine aldolase activity affects methionine gamma-lyase in Arabidopsis. Further research showed that threonine deaminase and methionine gamma-lyase both contribute to isoleucine biosynthesis in plants. Therefore, isoleucine content can be altered by manipulating the expression of either or both of these enzymes. Additionally, both enzymes contribute to the up to 100-fold increase in isoleucine that is observed in drought-stressed Arabidopsis. Toward the end of the project it was discovered that through different projects, both groups had been able to independently up-regulate phenylalanine accumulation by different mechanisms. The Galili lab transformed Arabidopsis with a feedbackinsensitive bacterial enzyme and the Jander lab found a feedback insensitive mutation in Arabidopsis arogenate dehydratase. Exchange of the respective plant lines has allowed a comparative analysis of the different methods for increasing phenylalanine content and the creation of double mutants. The research that was conducted as part of this BARD project has led to new insights into plant amino acid metabolism. Additionally, new approaches that were found to increase the accumulation of threonine, isoleucine, and phenylalanine in plants have potential practical applications. Increased threonine and isoleucine levels can increase the nutritional value of crop plants. Elevated isoleucine accumulation may increase the osmotic stress tolerance of plants. Up-regulation of phenylalanine biosynthesis can be used to increase the production of downstream higher-value plant metabolites of biofuel feed stocks.

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Chepeliev, Maksym. The GTAP 10A Data Base with Agricultural Production Targeting Based on the Food and Agricultural Organization (FAO) Data. GTAP Research Memoranda, September 2020. http://dx.doi.org/10.21642/gtap.rm35.

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This document describes a new source of inputs, based on FAO data, that allows us to estimate agricultural output targets on 133 regions of the GTAP 10A Data Base. This approach allows to overcome several limitations present under the current agricultural production targeting (APT) processing. First, a significant expansion in the regional coverage is achieved, as the number of regions undergoing APT more than doubles. Second, the detailed commodity classification of the FAO dataset allows for a more accurate mapping to the GTAP Data Base sectors. Third, a better commodity coverage in the FAO data prevents the issue of mapping a processed commodities to the corresponding primary sector. Finally, reliance on the FAO agricultural output data provides a better opportunity for further incorporation of the nutritional accounts to the GTAP Data Base, by lowering inconsistencies between GTAP and FAO agricultural accounting. Comparisons between OECD-based agricultural output (currently used in the GTAP Data Base) and FAO-derived estimates are provided in the document. FAO-based agricultural production targets are incorporated to the GTAP 10A Data Base build stream to produce a special release of the GTAP Data Base. JEL classification: C68, D57, D58, Q10, Q11. Keywords: Agricultural production targeting, GTAP Data Base, Computable general equilibrium.

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Barash, Itamar, and Robert Rhoads. Translational Mechanisms Governing Milk Protein Levels and Composition. United States Department of Agriculture, 2006. http://dx.doi.org/10.32747/2006.7696526.bard.

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Original objectives: The long-term goal of the research is to achieve higher protein content in the milk of ruminants by modulating the translational apparatus of the mammary gland genetically, nutritionally, or pharmacologically. The short-term objectives are to obtain a better understanding of 1) the role of amino acids (AA) as regulators of translation in bovine and mouse mammary epithelial cells and 2) the mechanism responsible for the synergistic enhancement of milk-protein mRNA polyadenylation by insulin and prolactin. Background of the topic: In many cell types and tissues, individual AA affect a signaling pathway which parallels the insulin pathway to modulate rates and levels of protein synthesis. Diverse nutritional and hormonal conditions are funneled to mTOR, a multidomain serine/threonine kinase that regulates a number of components in the initiation and elongation stages of translation. The mechanism by which AA signal mTOR is largely unknown. During the current grant period, we have studied the effect of essential AA on mechanisms involved in protein synthesis in differentiated mammary epithelial cells cultured under lactogenic conditions. We also studied lactogenic hormone regulation of milk protein synthesis in differentiated mammary epithelial cells. In the first BARD grant (2000-03), we discovered a novel mechanism for mRNA-specific hormone-regulated translation, namely, that the combination of insulin plus prolactin causes cytoplasmic polyadenylation of milk protein mRNAs, which leads to their efficient translation. In the current BARD grant, we have pursued the signaling pathways of this novel hormone action. Major conclusions/solutions/achievements: The positive and negative signaling from AA to the mTOR pathway, combined with modulation of insulin sensitization, mediates the synthesis rates of total and specific milk proteins in mammary epithelial cells. The current in vitro study revealed cryptic negative effects of Lys, His, and Thr on cellular mechanisms regulating translation initiation and protein synthesis in mammary epithelial cells that could not be detected by conventional in vivo analyses. We also showed that a signaling pathway involving Jak2 and Stat5, previously shown to lead from the prolactin receptor to transcription of milk protein genes, is also used for cytoplasmic polyadenylation of milk protein mRNAs, thereby stabilizing these mRNAs and activating them for translation. Implications: In vivo, plasma AA levels are affected by nutritional and hormonal effects as well as by conditions of exercise and stress. The amplitude in plasma AA levels resembles that applied in the current in vitro study. Thus, by changing plasma AA levels in the epithelial cell microenvironment or by sensitizing the mTOR pathway to their presence, it should be possible to modulate the rate of milk protein synthesis. Furthermore, knowledge that phosphorylation of Stat5 is required for enhanced milk protein synthesis in response to lactogenic opens the possibility for pharmacologic approaches to increase the phosphorylation of Stat5 and, thereby, milk protein production.

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Schwartz, Bertha, Vaclav Vetvicka, Ofer Danai, and Yitzhak Hadar. Increasing the value of mushrooms as functional foods: induction of alpha and beta glucan content via novel cultivation methods. United States Department of Agriculture, January 2015. http://dx.doi.org/10.32747/2015.7600033.bard.

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During the granting period, we performed the following projects: Firstly, we differentially measured glucan content in several pleurotus mushroom strains. Mushroom polysaccharides are edible polymers that have numerous reported biological functions; the most common effects are attributed to β-glucans. In recent years, it became apparent that the less abundant α-glucans also possess potent effects in various health conditions. In our first study, we explored several Pleurotus species for their total, β and α-glucan content. Pleurotuseryngii was found to have the highest total glucan concentrations and the highest α-glucans proportion. We also found that the stalks (stipe) of the fruit body contained higher glucan content then the caps (pileus). Since mushrooms respond markedly to changes in environmental and growth conditions, we developed cultivation methods aiming to increase the levels of α and β-glucans. Using olive mill solid waste (OMSW) from three-phase olive mills in the cultivation substrate. We were able to enrich the levels mainly of α-glucans. Maximal total glucan concentrations were enhanced up to twice when the growth substrate contained 80% of OMSW compared to no OMSW. Taking together this study demonstrate that Pleurotuseryngii can serve as a potential rich source of glucans for nutritional and medicinal applications and that glucan content in mushroom fruiting bodies can be further enriched by applying OMSW into the cultivation substrate. We then compared the immune-modulating activity of glucans extracted from P. ostreatus and P. eryngii on phagocytosis of peripheral blood neutrophils, and superoxide release from HL-60 cells. The results suggest that the anti-inflammatory properties of these glucans are partially mediated through modulation of neutrophileffector functions (P. eryngiiwas more effective). Additionally, both glucans dose-dependently competed for the anti-Dectin-1 and anti-CR3 antibody binding. We then tested the putative anti-inflammatory effects of the extracted glucans in inflammatory bowel disease (IBD) using the dextran sulfate sodium (DSS)–induced model in mice. The clinical symptoms of IBD were efficiently relieved by the treatment with two different doses of the glucan from both fungi. Glucan fractions, from either P. ostreatus or P. eryngii, markedly prevented TNF-α mediated inflammation in the DSS–induced inflamed intestine. These results suggest that there are variations in glucan preparations from different fungi in their anti-inflammatory ability. In our next study, we tested the effect of glucans on lipopolysaccharide (LPS)-induced production of TNF-α. We demonstrated that glucan extracts are more effective than mill mushroom preparations. Additionally, the effectiveness of stalk-derived glucans were slightly more pronounced than of caps. Cap and stalk glucans from mill or isolated glucan competed dose-dependently with anti-Dectin-and anti-CR-3 antibodies, indicating that they contain β-glucans recognized by these receptors. Using the dextran sulfate sodium (DSS)-inflammatory bowel disease mice model, intestinal inflammatory response to the mill preparations was measured and compared to extracted glucan fractions from caps and stalks. We found that mill and glucan extracts were very effective in downregulatingIFN-γ and MIP-2 levels and that stalk-derived preparations were more effective than from caps. The tested glucans were equally effective in regulating the number of CD14/CD16 monocytes and upregulating the levels of fecal-released IgA to almost normal levels. In conclusion, the most effective glucans in ameliorating some IBD-inflammatory associated symptoms induced by DSS treatment in mice were glucan extracts prepared from the stalk of P. eryngii. These spatial distinctions may be helpful in selecting more effective specific anti-inflammatory mushrooms-derived glucans. We additionally tested the effect of glucans on lipopolysaccharide-induced production of TNF-α, which demonstrated stalk-derived glucans were more effective than of caps-derived glucans. Isolated glucans competed with anti-Dectin-1 and anti-CR3 antibodies, indicating that they contain β-glucans recognized by these receptors. In conclusion, the most effective glucans in ameliorating IBD-associated symptoms induced by DSS treatment in mice were glucan extracts prepared from the stalk of P. eryngii grown at higher concentrations of OMSW. We conclude that these stress-induced growing conditions may be helpful in selecting more effective glucans derived from edible mushrooms. Based on the findings that we could enhance glucan content in Pleurotuseryngii following cultivation of the mushrooms on a substrate containing different concentrations of olive mill solid waste (OMSW) and that these changes are directly related to the content of OMSW in the growing substrate we tested the extracted glucans in several models. Using dextran sulfate sodium (DSS)–inflammatory bowel disease (IBD) mice model, we measured the colonic inflammatory response to the different glucan preparations. We found that the histology damaging score (HDS) resulting from DSS treatment reach a value of 11.8 ± 2.3 were efficiently downregulated by treatment with the fungal extracted glucans, glucans extracted from stalks cultivated at 20% OMSWdownregulated to a HDS value of 6.4 ± 0.5 and at 80% OMSW showed the strongest effects (5.5 ± 0.6). Similar downregulatory effects were obtained for expression of various intestinal cytokines. All tested glucans were equally effective in regulating the number of CD14/CD16 monocytes from 18.2 ± 2.7 % for DSS to 6.4 ± 2.0 for DSS +glucans extracted from stalks cultivated at 50% OMSW. We finally tested glucans extracted from Pleurotuseryngii grown on a substrate containing increasing concentrations of olive mill solid waste (OMSW) contain greater glucan concentrations as a function of OMSW content. Treatment of rat Intestinal epithelial cells (IEC-6) transiently transfected with Nf-κB fused to luciferase demonstrated that glucans extracted from P. eryngii stalks grown on 80% OMSWdownregulatedTNF-α activation. Glucans from mushrooms grown on 80% OMSW exerted the most significant reducing activity of nitric oxide production in lipopolysaccharide (LPS) treated J774A.1 murine macrophages. The isolated glucans were tested in vivo using the Dextran Sodium Sulfate (DSS) induced colitis in C57Bl/6 mice and found to reduce the histology damaging score resulting from DSS treatment. Expression of various intestinal cytokines were efficiently downregulated by treatment with the fungal extracted glucans. We conclude that the stress-induced growing conditions exerted by OMSW induces production of more effective anti-inflammatory glucans in P. eryngii stalks.

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