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Les hypocholestérolémies génétiques représentent un ensemble de pathologies héréditaires du métabolisme caractérisées par une hypocholestérolémie inférieure au 5ème percentile pour l'âge et le sexe. Elles sont majoritairement dues à un défaut d'assemblage et de sécrétion des lipoprotéines entraînant, dès la période néonatale, une malabsorption des lipides et des vitamines liposolubles. Les conséquences à long terme peuvent être dramatiques (complications ophtalmologiques et neurologiques graves) si un traitement par vitamines liposolubles, en particulier vitamine E à fortes doses, n'est pas instauré rapidement. Pour ces raisons, l'étude clinique princeps a comparé une formulation de vitamine E rendue hydrosoluble (tocofersolan) à l'acétate de tocophérol liposoluble et traditionnellement utilisé en thérapeutique chez ces patients. En parallèle, un travail sur modèle cellulaire Caco2, nous a permis d'étudier les mécanismes d'absorption/sécrétion de ces deux formulations de vitamine E afin de mieux appréhender les mécanismes mis en jeu. Deux études méthodologiques ont été menées en amont de cette étude clinique. La première visait à vérifier la stabilité des échantillons dans les conditions de transport imposées par l'étude princeps. Par ailleurs, les concentrations effondrées de lipoprotéines chez ces patients rendent difficile l'évaluation du statut en vitamine E par les simples dosages plasmatiques. Aussi, la seconde étude avait pour but d'établir les valeurs usuelles pour les concentrations en vitamine E dans les globules rouges et le tissu adipeux chez l'enfant sain comme outil d'aide au suivi des patients atteints d'hypocholestérolémie génétique. Grâce aux valeurs de référence établies dans ce travail, l'analyse de la vitamine E dans les globules rouges et le tissu adipeux permet de proposer une vue plus globale du statut en vitamine E chez ces patients / Abetalipoproteinemia (ABL) and chylomicron retention disease (CMRD) are rare recessive forms of hypobetalipoproteinemia characterized by an intestinal lipid malabsorption and a severe vitamin E deficiency leading to disabling neuro-ophtalmologic sequelae. Oral a- tocopherol supplementation with high doses has to be initiated as early as possible to prevent or halt progression of complications. The main aim of our work was to investigate the interest of tocofersolan, a water-soluble derivative of RRR-α-tocopherol, compared to a-tocopherol acetate in ABL and CMRD. In parallel, we investigated the mechanisms of absorption / secretion of tocofersolan and a- tocopheryl acetate on Caco2 cells for a better understanding of the mechanisms of their therapeutic efficacy. Two methodological studies were conducted prior to this clinical study. Firstly, we studied the stability of commonly measured vitamins and carotenoids in whole blood in the conditions of transport imposed by the clinical study. Secondly, we established the reference intervals for vitamin E concentrations in red blood cells and adipose tissue in healthy child as a tool to monitore treatment of children with ABL and CMRD with vitamin E. Indeed, the very reduced lipoprotein concentrations in these patients make difficult the assesment of vitamin E status based on plasma a-tocopherol concentrations. The references values established in this work allows us to propose a more comprehensive view of the vitamin E status in these patients

Vitamin E was first described in 1922 as an unknown factor required for impregnated rats to carry their offspring to term. In fact, when vitamin E was chemically characterized it was given the name "tocopherol" derived from the Greek: tokos = childbirth; phero = to bear; and –ol, indicating an alcohol. Vitamin E is linked to animal health and wellness, maternal fertility and a human neurodegenerative condition, ataxia with vitamin E deficiency However, embryonic vitamin E requirements during development remained unknown. We hypothesized that vitamin E is critical, not only for the mother, but specifically by the embryo for proper development. To separate the embryonic and maternal requirements, we employed an innovative model for the study of vitamin E: the zebrafish. We began by formulating and testing the first fully defined diet sufficient for zebrafish health. We then removed vitamin E from the formula to create our E deficient (E-) diet, which, when fed to adult zebrafish (for >3 months), resulted in E- adults that produced viable, E- gametes. Deficient embryos initially developed normally; however, by 48 hours post fertilization (hpf), E- embryos developed severe malformations leading to significant mortality. Thus, we demonstrated for the first time an embryonic vitamin E requirement. We provided further insight into the embryonic vitamin E requirement by analyzing the transcriptional changes occurring prior to the observed malformations. The transcriptome revealed a putative mechanism of action for vitamin E in development, in which vitamin E deficiency leads to the dysregulation of key metabolic co-activators. Finally, to understand the trafficking of vitamin E, we identified the zebrafish α-tocopherol transfer protein (TTP). We demonstrated that the zebrafish TTP is homologous to its human counterpart, and its expression is both spatially and temporally regulated during embryonic development. Knocking down the expression of TTP, using morpholinos injected at the one-cell stage, resulted in early and severe malformations in the developing head and tail. Consequently we revealed a definitive role for TTP during development. Taken together the work described here presents a new direction for future research into the role of vitamin E and TTP in post-implantation development. / Graduation date: 2012

In dieser Arbeit wird die Eignung eines Haarwurzelsystems (HR) aus transgenen Sonnenblumen-hairy roots zur biotechnologischen Produktion von α-Tocopherol untersucht. Es wurden hairy roots mit und ohne Transgene erzeugt. Transgene HR exprimieren Tocopherolbiosynthesegene aus Arabidopsis thaliana. Die HR wurden unterschiedlichen Stressoren unterworfen, um die α-Tocopherolproduktion binnen eines Zeitraums zu überprüfen. Stressoren waren verringerte Kohlenstoffquelle, Beleuchtung und der Zusatz von Zytokininen. Die Produktionsleistung des Systems ist schlussendlich ungenügend zur kostengünstigen Produktion von α-Tocopherol.

In dieser Arbeit wird die Eignung eines Haarwurzelsystems (HR) aus transgenen Sonnenblumen-hairy roots zur biotechnologischen Produktion von α-Tocopherol untersucht. Es wurden hairy roots mit und ohne Transgene erzeugt. Transgene HR exprimieren Tocopherolbiosynthesegene aus Arabidopsis thaliana. Die HR wurden unterschiedlichen Stressoren unterworfen, um die α-Tocopherolproduktion binnen eines Zeitraums zu überprüfen. Stressoren waren verringerte Kohlenstoffquelle, Beleuchtung und der Zusatz von Zytokininen. Die Produktionsleistung des Systems ist schlussendlich ungenügend zur kostengünstigen Produktion von α-Tocopherol.

Le tocophérol, le phytostérol, le pourcentage de protéines des graines, l'huile et les teneurs en acides gras ont été mesurés dans une population de lignées recombinantes (RILS) de tournesol, cultivées sous conditions de sécheresse, irrigation et semis tardif. Une analyse génétique de QTL a été réalisée à partir de ces mesures, en utilisant une carte génétique basée sur des marques SSR et avec des gènes candidats (1) impliqués dans la voie métabolique de tocophérol et phytostérol, (2) des gènes codant des antioxydants enzymatiques, (3) des gènes liés à la sécheresse et (4) des gènes homologues à SEC14 chez Arabidopsis. Trois gènes candidats importants (VTE4, VTE2 et HPPD), qui codent pour des enzymes impliquées dans la biosynthèse du tocophérol, ont été cartographiés sur les groupes de liaison LG8 et LG14. Quatre SNPs sont identifiés pour PAT2, le gène homologue chez Arabidopsis SEC14, entre les deux parents (PAC2 et RHA266) et un SNP, identifié par alignement de séquences est converti en marqueur CAPS pour permettre l'analyse génotypique des RIL. Les gènes homologues à SFH3, HPPD, CAT et CYP51G1 ont été cartographiés grâce à la mise au point de marqueurs dominants, tandis que des marqueurs co-dominants ont permis la cartographie des gènes homologues à SEC14-1, VTE4, DROU1, POD, SEC14-2 et AQUA. Les gènes POD, CAT et GST, codant pour des antioxydants enzymatiques, ont également été cartographiés sur les groupes de liaison 17, 8 et 1, respectivement. Le QTL majeur pour la teneur en tocophérol a été identifié sur le groupe de liaison 8, qui explique 59,5% de la variation phénotypique (6.TTC.8). Il colocalsie également avec le QTL identifié pour la teneur en phytostérol (7.TPC.8). Sous condition de semis tardif, un QTL spécifique de la teneur en acide palmitique a été identifié sur le groupe de liaison 6 (PAC-LS.6). Il est situé entre les marqueurs ORS1233 et SSL66_1. Les QTLs pour le pourcentage d'huile de graines et la teneur en acide stéarique colocalisent sur les groupes de liaison 10 (PSO-PI.10 et SAC-WI.10) et 15 (PSO-PI.15 et SAC-LS.15). Sept QTLs associés à teneur en acides palmitique, stéarique, oléique et linoléique sont identifiés sur le groupe de liaison 14. Ils sont liés à l’homologue du gène HPPD. Par ailleurs, les caractères agronomiques tels que les jours du semis à la floraison, la hauteur des plantes, le rendement et la morphologie foliaire ont été étudiés. Des analyses association génétique ont permis d’identifier des QTLs intérêts sur les groupes de liaison 2, 10 et 13 pour les caractères étudiés, d’autres QTLs identifies sur les groupes de liaison 9 et 12 mettent en avant l'importance de ces régions génomiques pour les caractères de morphologie foliaire. Nous avons finalement identifié des marqueurs AFLP et quelques gènes candidats liés aux caractères impliqués dans la qualité des graines sous conditions irriguée et stress hydrique chez une population de mutants (M8). Deux lignées mutantes, M8-826-2-1 et M8-39-2-1, produisent un niveau significativement élevé d'acide oléique peuvent être utilisées dans les programmes de sélection en raison de la haute stabilité à l'oxydation et des propriétés cardiovasculaire apportés par l’acide oléique qu’elles produisent. L'augmentation du niveau de tocophérol dans les lignées mutantes, M8-862-1N1 et M8-641-2-1, est justifiée par le polymorphisme observé pour le gène, MCT, impliqué dans la voie métabolique du tocophérol. Le marqueur le plus important pour le contenu en tocophérol total est E33M50_16 qui explique 33,9% de la variation phénotypique. Un des gènes candidats les plus importants concernant la biosynthèse des acides gras, FAD2 (FAD2-1), est lié à la teneur en acides oléique et linoléique. Il explique plus de 52% de la variation phénotypique. / The genetic control of tocopherol, phytosterol, percentage of seed protein, oil and fatty acids content in a population of recombinant inbred lines (RILs) of sunflower under various conditions are studied through QTL analysis using genetic-linkage map based on SSR markers and introducing some important tocopherol and phytosterol pathway-related genes, enzymatic antioxidant-related genes, droughtresponsive family genes and Arabidopsis SEC14 homologue genes. Three important candidate genes (HPPD, VTE2 and VTE4), which encode enzymes involved in tocopherol biosynthesis, are mapped to linkage group 8(LG8) and LG14. One of the most important candidate genes coding for sterol methyltransferase II (SMT2) enzyme is anchored to LG17 by CAPS marker. Four SNPs are identified for PAT2, Arabidopsis Sec14 homologue gene, between two parents (PAC2 and RHA266). PAT2 is assigned to LG2 by CAPS marker. Squalene epoxidase (SQE1) is also assigned to LG15 by InDel marker. Through other candidate genes, POD, CAT and GST encoding enzymatic antioxidants are assigned to LG17, LG8 and LG1, respectively. The major QTL for total tocopherol content on linkage group 8 accounted for 59.5% of the phenotypic variation (6.TTC.8), which is overlapped with the QTL of total phytosterol content (7.TPC.8). Under late-sowing condition, a specific QTL of palmitic acid content on linkage group 6 (PAC-LS.6) is located between ORS1233 and SSL66_1 markers. Common chromosomic regions are observed for percentage of seed oil and stearic acid content on linkage group 10 (PSO-PI.10 and SACWI. 10) and 15 (PSO-PI.15 and SAC-LS.15). Overlapping occurs for QTLs of oleic and linoleic acids content on linkage groups 10, 11 and 16. Seven QTLs associated with palmitic, stearic, oleic and linoleic acids content are identified on linkage group 14. These common QTLs are linked to HPPD homologue, HuCL04260C001. QTLs controlling various traits such as days from sowing to flowering, plant height, yield and leaf-related traits are also identified under well-, partial-irrigated and late-sowing conditions in a population of recombinant inbred lines (RILs). The results do emphasis the importance of the role of linkage group 2, 10 and 13 for studied traits. Genomic regions on the linkage group 9 and 12 are important for QTLs of leaf-related traits in sunflower. We finally identified AFLP markers and some candidate genes linked to seed-quality traits under well-irrigated and water-stressed conditions in gammainduced mutants of sunflower. Two mutant lines, M8-826-2-1 and M8-39-2-1, with significant increased level of oleic acid can be used in breeding programs because of their high oxidative stability and hearthealthy properties. The significant increased level of tocopherol in mutant lines, M8-862-1N1 and M8- 641-2-1, is justified by observed polymorphism for tocopherol pathway-related gene; MCT. The most important marker for total tocopherol content is E33M50_16 which explains 33.9% of phenotypic variance. One of the most important candidate genes involving fatty acid biosynthesis, FAD2 (FAD2-1), is linked to oleic and linoleic acids content and explained more than 52% of phenotypic variance.

This thesis is concerned with the synthesis and evaluation of various tellurium-based chain-breaking antioxidants. The purpose is to find novel regenerable compounds with improved radical-trapping capacity. In the first part of this work, we explore the possibilities to incorporate tellurium into tocopherols and aromatic amines. Overall, tocopherols carrying alkyltelluro groups are better radical-trapping agents than the corresponding sulfur- and selenium analogues. Among them, 7-octyltelluro δ-tocopherol showed a ca. 17-fold higher reactivity than recorded for α-tocopherol and much better regenerability. Even longer inhibition times were recorded for the corresponding bis(tocopheryl) tellurides. In the aromatic amine series, diphenyl amines carrying alkyltelluro groups were shown to function as efficient radical-quenchers capable of inhibiting peroxidation for 460 min in the presence of N-acetylcysteine. Thiol-consumption experiments suggested that the long inhibition times are due to efficient quenching of in-situ formed alkoxyl radicals in a solvent cage. In the second part of the thesis, we study how the antioxidant properties are affected by variations in the electron density at tellurium and the number of alkyltelluro substituents in the molecule. Evaluation of a series of aryltelluro phenols carrying electron donating and electron withdrawing groups in the para-position of the aryl moiety suggested that a high electron density at the heteroatom prolonged the inhibition time. Among alkyltelluro phenols, alkyltelluro resorcinols and bis(alkyltelluro) phenols, phenols carrying alkyltelluro groups in both ortho positions were superior when it comes to radical-trapping activity and regenerability.

Leaves are responsible for the majority of the fixed carbon in most plant species. Along leaf development, the photosynthetic capacity increases until the organ reaches maturity. Consequently, at the onset of senescence the leaves have the highest photosynthetic activity, then, as the chloroplasts are dismantled and the photosynthetic machinery is degraded, leaves gradually lose the rate of carbon assimilation. Although the capacity to fix carbon declines as senescence progresses, nutrient remobilization from macromolecule degradation nourishes the developing sink organs. In this regard, delaying leaf senescence stands out as a promising strategy to increase plant yield as extends the window of time with maximum carbon fixation rate. Another approach that is receiving much attention is the manipulation of chlorophyll degradation once it potentially regulates photosynthetic capacity and affects the nutritional quality of harvestable organs. As chlorophyll is degraded, the released phytol is recycled and can be either stored (i.e. as fatty acid phytyl esters), used for chlorophyll synthesis or be incorporated in tocopherol biosynthesis. Tocopherols have high nutraceutical value due to their antioxidant properties. However, the majority of the studies regarding senescence and chlorophyll degradation were carried out in the model plant Arabidopsis thaliana or grasses, creating a knowledge gap about these processes in fleshy fruit-bearing plants of human diet interest. In this regard, the tomato, Solanum lycopersicum, is an excellent model not only for the genetic and genomic resources, but also for its agronomic and nutritional importance. Thus, this project aims to extend what is known about the effects of chlorophyll degradation and senescence manipulation over the metabolism and yield of tomato plants, as well as fruit nutritional quality. In order to evaluate the consequences of alteration in chlorophyll degradation, first the enzymes chlorophyllase and pheophytinase, both capable of dephytylating the chlorophyll molecule, were identified and characterised. An extensive phylogenetic, evolutive and transcriptional analysis allowed the identification of two groups of chlorophyllases, one putatively involved in the response to different stimuli, while the other may act in chlorophyll homeostasis. As for pheophytinase, only one group was identified, being related to physiologically programmed processes that trigger chlorophyll degradation (i.e. leaf senescence and fruit ripening). Given this scenario, pheophytinase was chosen to be constitutively knocked-down in order to evaluate the effects over the metabolism of leaves and fruits. As consequence of this manipulation, transgenic plants were impaired in the leaf senescence-associated chlorophyll breakdown, but, although with an initial delay, fruit ripening-associated degreening was not compromised. Several photosynthetic and biochemical parameters were signs of photoinhibition, possibly due to a deficiency in chlorophyll recycling in leaves. This led to an increase in sugar exportation towards fruits, ultimately increasing soluble sugar content of ripe fruits. However, as a consequence, carotenoid levels were reduced, what, at least partially, it was compensated by an increase in tocopherol content. The results indicated that pheophytinase plays a role beyond senescence-associated chlorophyll degradation and its manipulation led to the development of fruit with increased soluble sugars and tocopherols at the cost of lowering carotenoid levels. Thus, these evidences support the manipulation of chlorophyll breakdown as a strategy for improvement of fleshy fruit plants. In order to address the effects of senescence over yield and fruit quality, the transcription factor ORESARA1, which has been widely characterised in A. thaliana and is considered a key regulator of senescence initiation, was targeted. After a comprehensive phylogenetic analysis and the characterization of the regulatory mechanisms, one putative ortholog was selected to be silenced. As consequence of this manipulation, leaves displayed increased chlorophyll content. Moreover, as senescence was delayed, the extent of photosynthetic activity of the leaves was also expanded. As the number of fruits was increased in the knockdown lines, this reflected in an increment in the harvest index. Ripe fruits accumulated more soluble sugars and tocopherols. Collectively, the results support the manipulation of leaf senescence as a strategy for tomato yield improvement. Altogether, data obtained enhance the knowledge about the impacts of chlorophyll degradation and leaf senescence over the metabolism of fleshy-fruit plants, providing strategies to increase yield and nutritional quality of fruits / As folhas, para a maioria das espécies vegetais, são o principal órgão responsável pela fixação de carbono. Durante o desenvolvimento foliar, o potencial fotossintético aumenta até a folha atingir a sua maturidade. Consequentemente, no momento que o programa de senescência se inicia, a folha apresenta a maior taxa de fotossíntese, a qual passa então a declinar conforme o cloroplasto se desorganiza e a maquinaria fotossintética é degradada. Apesar da redução na fixação de carbono, o catabolismo de macromoléculas possibilita a remobilização de nutrientes para os órgãos dreno em desenvolvimento. Neste contexto, atrasar a senescência destaca-se como uma promissora estratégia para aumento da produtividade, uma vez que estende o período de máxima fixação de carbono das folhas. Outra estratégia que tem recebido atenção por, potencialmente, regular a capacidade fotossintética e afetar a qualidade nutricional dos órgãos coletáveis é a manipulação da degradação da clorofila. Durante o catabolismo deste pigmento, o fitol liberado é reciclado podendo ser armazenado (i.e. na forma de ésteres de fitil com ácidos graxos), ser utilizado na síntese de novas moléculas de clorofila ou ser incorporado na rota biossintética de tocoferóis. Estes últimos compostos, por seu potencial antioxidante, possuem alto valor nutracêutico. No entanto, a maior parte dos estudos sobre senescência e degradação de clorofila foi realizada na planta modelo Arabidopsis thaliana ou em gramíneas, tornando escassas as informações relativas a plantas com frutos carnosos de interesse para a dieta humana. Nesse âmbito, o tomateiro, Solanum lycopersicum, é um excelente modelo de estudo não apenas pela disponibilidade de recursos genético e genômicos, mas também pela importância agronômica e nutricional desta espécie. Assim, este trabalho pretende expandir o conhecimento acerca dos efeitos da manipulação da degradação de clorofila e da senescência sobre o metabolismo e produtividade do tomateiro, bem como sobre a qualidade nutricional dos frutos. De modo a se avaliar as consequências de alterações na degradação de clorofila, iniciou-se por identificar e caracterizar em tomateiro as enzimas clorofilase e feofitinase, as quais catalisam a defitilação da molécula de clorofila. Uma vasta análise filogenética, evolutiva e transcricional permitiu a identificação de dois grupos de clorofilases, um dos quais estaria envolvido na plasticidade de respostas a estímulos e o outro na homeostase dos níveis de clorofila. Já para feofitinase, somente um grupo foi identificado, o qual está relacionado a processos fisiologicamente programados que levam à degradação de clorofila (i.e. senescência foliar e amadurecimento de frutos). Dado o panorama obtido, a feofitinase foi escolhida para ser constitutivamente silenciada de modo a se avaliar as consequências para o metabolismo de folhas e frutos. Como consequência do silenciamento, as linhagens transgênicas mostraram-se incapazes de degradar clorofila durante a senescência, mas, embora com um atraso nas etapas iniciais, a degradação ao longo do amadurecimento de frutos não foi comprometida. Diversos parâmetros fotossintéticos e bioquímicos foram indicativos de fotoinibição, possivelmente em virtude de uma deficiência na reciclagem da clorofila em folhas. Isto acarretou em um aumento na exportação de açúcares para frutos, incrementando a concentração de açúcares solúveis nos frutos maduros, que, em contrapartida, resultou na queda nos teores de carotenoides. A queda nestes compostos antioxidantes foi, ao menos parcialmente, compensada por um aumento nos níveis de tocoferóis. Os resultados indicaram que a feofitinase possui um papel além da degradação de clorofila associada à senescência, e que sua manipulação leva ao desenvolvimento de frutos com maior teor de açúcares solúveis e de tocoferóis ao custo da redução no de carotenoides. Desta forma, estas evidências suportam a manipulação da clorofila como estratégia para o melhoramento de frutos carnosos. Para investigar o efeito da senescência sobre a produtividade e qualidade de frutos foi escolhido o fator de transcrição ORESARA1, o qual está amplamente caracterizado em A. thaliana e é considerado um regulador chave no desencadeamento deste processo. A partir de uma extensa análise filogenética e da caracterização de sua regulação, um putativo ortólogo foi selecionado como alvo para silenciamento. Como consequência desta manipulação, folhas apresentaram os níveis de clorofila incrementados. Além disto, taxas fotossintéticas maiores que as do genótipo controle foram mantidas por maior tempo indicando que a iniciação da senescência foi retardada. Assim, estas plantas produziram um maior número de frutos, consequentemente, aumentando o índice de colheita dessas linhagens. Os frutos maduros apresentaram maiores teores de açúcares solúveis e de tocoferóis. Os resultados demostraram que o retardo do início da senescência é uma estratégia efetiva para aumento da produtividade de tomateiro. Coletivamente, os resultados obtidos aprofundam o conhecimento acerta dos impactos da degradação de clorofila e senescência sobre o metabolismo de plantas com frutos carnoso, além de prover estratégias para se incrementar a produtividade e a qualidade nutricional de frutos

O objetivo deste trabalho foi estudar os efeitos da administração parenteral de vitamina E no desempenho produtivo e na sensibilidade à insulina de cordeiros nascidos de ovelhas suplementadas ou não com vitamina E no 108º dia de gestação. Foram utilizados 28 cordeiros em delineamento de blocos casualizados, considerando o sexo dos cordeiros e tipo de gestação, se única ou gemelar; com planejamento fatorial 2X2, em que foram considerados cordeiros de ovelhas que receberam ou não vitamina E e cordeiros que receberam ou não vitamina E na dosagem de 60 UI/kg PV até 24 horas após o nascimento, distribuindo em quatro grupos: EE: Cordeiros e ovelhas que receberam vitamina E; EC: Cordeiros que receberam veículo oleoso (controle) nascidos de ovelhas que receberam vitamina E; CC: Cordeiros e ovelhas que receberam veículo oleoso; CE: Cordeiros que receberam vitamina E nascidos de ovelhas que receberam veículo oleoso. Para detecção da sensibilidade à insulina, aos 28 dias de vida (T1) os cordeiros foram submetidos ao teste de tolerância à glicose (TTG). Foram determinados aos dois (T0) e aos 28 (T1) dias de vida as atividades de CK, AST, GGT, SOD, GSH-Px; o status antioxidante total (TAS); a habilidade de redução do ferro plasmático (HRFP), as substâncias reativas ao ácido tiobarbitúrico (TBARs); as concentrações de ácido úrico, glicose, ácidos graxos não esterificados (AGNE), betahidroxibutirato (BHB), triglicerídeos, colesterol, cálcio total, cálcio ionizável, proteína total, albumina, ureia, creatinina e a concentração plasmática de vitamina E (alfa-tocoferol). Foram calculados os valores de RQUICKI e de RQUICKI BHB em T0 e em T1. Semanalmente foram acompanhados o peso e o escore de condição corporal dos cordeiros (ECC). Os dados foram analisados utilizando-se o pacote estatístico STATISTICAL ANALYSIS SYSTEM (SAS) e para todos os testes foi adotado o nível de significância de 5%. A administração parenteral de 60 UI/kg de vitamina E em ovelhas no 108o dia de gestação e/ou nas primeiras 24 horas de vida de cordeiros não influenciou as concentrações de cálcio total, proteína total, ureia, albumina, TAS, cortisol, insulina; as concentrações plasmáticas de glicose, colesterol, triglicérides, AGNE, HRFP; as atividades de AST, GGT, GSH-Px e SOD; e os valores de RQUICKI, peso e ECC. Foi observada diminuição da sensibilidade à insulina e concentração de alfa tocoferol no T0 para cordeiros nascidos de ovelhas suplementadas com vitamina E. A suplementação dos cordeiros melhorou o status antioxidante no T0 e a produção de BHB no T1. A suplementação com alfa tocoferol não influenciou no peso vivo e no ECC até a quarta semana de vida do cordeiro. / The objective of this work was to study the effects of parenteral administration of vitamin E on the productive performance and insulin sensitivity of lambs born from ewes supplemented or not with vitamin E on the 108th day of gestation. Twenty-eight lambs received intramuscularly 60 UI/kg BW of vitamin E or oily vehicle until 24 hours after birth and were distributed according to their sex and type of pregnancy (single or twin) into four groups using a 2x2 factorial design: EE: lambs and ewes treated with vitamin E; EC: Lambs that received oily vehicle (control) born from ewe treated with vitamin E; CC: Lambs and ewe that received oily vehicle; EC: Lambs that received vitamin E born from ewe treated with the oily vehicle. At 28 days old, all lambs were submitted to the glucose tolerance test (GTT). At 28 days old, all lambs were submitted to the glucose tolerance test (GTT) to detect insulin sensitivity. The activities of CK, AST, GGT, SOD, GSH-Px; total antioxidant status (TAS); the ability to reduce plasma iron (HRFP), thiobarbituric acid reactive substances (TBARs); the concentrations of uric acid, glucose, non-esterified fatty acids (NEFA), betahydroxybutyrate (BHB), triglycerides, cholesterol, total calcium, ionizable calcium, total protein, albumin, urea, creatinine and plasma concentration of vitamin E (alpha-tocopherol) were determined at 2 (T0) and at 28 (T1) days of life. The RQUICKI and RQUICKI BHB values were calculated in T0 and T1. The body condition score (BCS) and the live weight were measured every week. The data were analyzed using the statistical package STATISTICAL ANALYSIS SYSTEM (SAS) and for all the tests was adopted the level of significance of 5%. Parenteral administration of 60 IU / kg vitamin E in sheep on the 108th day of gestation and / or during the first 24 hours of lamb life did not influence the concentrations of total calcium, total protein, urea, albumin, TAS, cortisol, insulin; plasma concentrations of glucose, cholesterol, triglycerides, NEFA, FRAP; the activities of AST, GGT, GSH-Px and SOD; and the RQUICKI, weight and BSC values. There was only effect related to the age of the lambs for these variables. Decreased insulin sensitivity and increased alpha tocopherol concentration was observed in T0 for lambs born from ewe supplemented with vitamin E. The supplementation of the lambs improved the antioxidant status in T0 and the BHB production in T1. Alfa Tocopherol supplementation did not influence the live weight and BSC until the fourth week of life of the lambs.

O presente estudo teve por objetivo avaliar os efeitos da administração intramuscular de alfa-tocoferol (vitamina E) sobre marcadores de estresse fisiológico e oxidativo, além de características relacionadas à qualidade da carne de cordeiros submetidos a transporte rodoviário de curta duração. Vinte e quatro cordeiros, mestiços das raças Santa Inês e Dorper, com idade e peso vivo médios ao abate de 138 dias e 43,6 kg, respectivamente, foram distribuídos em três grupos experimentais nos quais receberam, aos seis e três dias antes do transporte, pela via intramuscular, uma aplicação de solução fisiológica; 10 UI; ou 20 UI de acetato de DL-alfa-tocoferol, por quilo de peso metabólico. O transporte teve duração de quatro horas e na chegada ao abatedouro, os cordeiros desembarcaram em curral de espera, onde permaneceram por 19 horas até o momento do abate. Nos momentos T0 (imediatamente antes do embarque e transporte); T1 (imediatamente após transporte e desembarque); T2 (três horas após transporte e desembarque) e T3 (imediatamente antes do abate) foi aferida a temperatura retal e coletadas amostras de sangue por punção da veia jugular para determinação das concentrações séricas de ureia, creatinina, albumina, proteína total, colesterol e cortisol; concentrações plasmáticas de glicose, beta-hidroxibutirato (BHB), lactato e ácidos graxos não esterificados (AGNE); atividade sérica da creatinofosfoquinase (CK); contagem de hemácias e leucócitos totais; relação neutrófilos:linfócitos; volume globular (VG); atividades eritrocitárias da superóxido dismutase (SOD), glutationa peroxidase (GPx) e glutationa redutase (GR); concentração de glutationa reduzida (GSH); status antioxidante total do soro (TAS) e concentração de substâncias reativas ao ácido tiobarbitúrico (TBARS). Após o abate, as carcaças foram mantidas por 24 horas sob refrigeração a 2°C para que pudessem ser determinados o pH (pH24h) e coloração (L*, a*, b*) do músculo Longissimus dorsi, além de coletadas amostras para posterior avaliação da força de cisalhamento (FC), perdas de peso por cozimento (PPC) e produtos da oxidação lipídica após 30 dias de congelamento (TBARS 30). Houve efeito de interação entre momento e tratamento para lactato, sendo observado efeito linear de tratamento no momento T2, com maiores (P= 0,0111) valores dessa variável nos animais que receberam 20 UI de vitamina E. Ocorreu efeito linear de tratamento (P=0,0149) sobre os valores de TAS. Foi observado efeito de desvio da linearidade para albumina, L* e b*. Animais que receberam 10 UI de vitamina E apresentaram menores concentrações de albumina (P= 0,0447) e maiores valores (P=0,0042 e P=0,0082) de L* e b*. Com exceção da temperatura retal e GR, foi observado efeito de momento para todos os outros marcadores de estresse fisiológico e oxidativo. O transporte rodoviário de curta duração, mesmo quando realizado de maneira adequada, gera estresse nos animais. Estímulos potencialmente nocivos no momento prévio ao abate levaram a estresse de maior intensidade que aquele oriundo do transporte. A administração intramuscular de alfa-tocoferol aumentou o status antioxidante total do soro de cordeiros submetidos a transporte rodoviário de curta duração, entretanto não foi capaz de minimizar as alterações decorrentes do estresse fisiológico e oxidativo e de melhorar a qualidade da carne destes animais. / The present study aimed to evaluate the effects of intramuscular alpha-tocopherol (vitamin E) administration on markers of oxidative and physiological stress, as well characteristics related to meat quality of lambs subjected to road short transport. Twenty-four lambs, Santa Inês and Dorper crossbred, age and average live weight at slaughter of 138 days and 43.6 kg, respectively, were divided into three experimental groups. Each group received an intramuscular application of saline solution or 10 IU or 20 IU of DL-alpha-tocopherol per kg of metabolic body weight at six and three days before transportation. The transportation lasted four hours until the slaughterhouse. After unloading, lambs rested in pen for 19 hours until the time of slaughter. At T0 (immediately prior to boarding and transportation), T1 (immediately after transport and unloading), T2 (three hours after transporting and landing) and T3 (immediately before slaughter) rectal temperature was measured and blood samples were collected by jugular vein puncture for determination of serum urea, creatinine, albumin, total protein, cholesterol and cortisol; plasma concentrations of glucose, beta-hydroxybutyrate (BHB), lactate and non-esterified fatty acids (NEFA); serum activities of aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT) and creatine kinase (CK), erythrocyte and total leukocyte count, ratio neutrophil: lymphocytes, packed cell volume (PCV), erythrocyte activities of superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GR), concentration of reduced glutathione (GSH), serum total antioxidant status (TAS) and the concentration of thiobarbituric acid reactive substances (TBARS). After slaughter, carcasses were kept for 24 hours under refrigeration at 2 °C and were analyzed for Longissimus Dorsi pH (pH24h) and color (L *, a *, b *), and collected samples for subsequent evaluation of shear force (SF), cooking weight loss (CWL) and products of lipid oxidation after 30 days of freezing (TBARS 30). There was an interaction between time and treatment for lactate and was observed a linear effect at the time T2, with increased (P = 0.0111) values of this variable in the animals receiving 20 IU of vitamin E. A linear effect of treatment (P = 0.0149) on the TAS values was observed. Deviation from linearity effect for albumin, L * and b * were seen. Animals that received 10 IU of vitamin E showed lower concentrations of albumin (P = 0.0447) and higher (P = 0.0042 and P = 0.0082) L * and b * values. Except for rectal temperature and GR, moment effect was observed for all other markers of oxidative and physiological stress. The short road transportation, even when done properly, produces stress in animals. Potentially harmful stimuli at the time prior to slaughter led to higher stress intensity than that coming from the transport. Intramuscular administration of alpha-tocopherol increased serum total antioxidant status of lambs subjected to short duration road transport, however was not able to minimize changes arising from physiological and oxidative stress and improve the meat quality of these animals.