Auswahl der wissenschaftlichen Literatur zum Thema „Sub-Optimal diet“

Evidence for diet quality representing a modifiable risk factor for age-related cognitive decline and mood disturbances has typically come from retrospective, cross-sectional analyses. Here a diet screening tool (DST) was used to categorize healthy middle-aged volunteers (n = 141, 40–65 years) into “optimal” or “sub-optimal” diet groups to investigate cross-sectional associations between diet quality, cognitive function, and mood. The DST distinguished levels of nutrient intake as assessed by Automated Self-Administered 24-h dietary recall and nutrient status, as assessed by blood biomarker measures. Compared with the “sub-optimal” group, the “optimal” diet group showed significantly higher intake of vitamin E (p = 0.007), magnesium (p = 0.001), zinc (p = 0.043) and fiber (p = 0.015), higher circulating levels of vitamin B6 (p = 0.030) and red blood cell folate (p = 0.026) and lower saturated fatty acids (p = 0.012). Regarding psychological outcomes, the “optimal” diet group had significantly better Stroop processing than those with a “sub-optimal” diet (p = 0.013). Regression analysis revealed that higher DST scores were associated with fewer mood disturbances (p = 0.002) and lower perceived stress (p = 0.031), although these differences were not significant when comparing “optimal” versus “sub-optimal” as discrete groups. This study demonstrates the potential of a 20-item diet screen to identify both nutritional and psychological status in an Australian setting.

Research in both animals and humans shows that some nutrients are important in pregnancy and during the first years of life to support brain and cognitive development. Our aim was to evaluate the role of selenium (Se) in supporting brain and behavioral plasticity and maturation. Pregnant and lactating female rats and their offspring up to postnatal day 40 were fed isocaloric diets differing in Se content—i.e., optimal, sub-optimal, and deficient—and neurodevelopmental, neuroinflammatory, and anti-oxidant markers were analyzed. We observed early adverse behavioral changes in juvenile rats only in sub-optimal offspring. In addition, sub-optimal, more than deficient supply, reduced basal glial reactivity in sex dimorphic and brain-area specific fashion. In female offspring, deficient and sub-optimal diets reduced the antioxidant Glutathione peroxidase (GPx) activity in the cortex and in the liver, the latter being the key organ regulating Se metabolism and homeostasis. The finding that the Se sub-optimal was more detrimental than Se deficient diet may suggest that maternal Se deficient diet, leading to a lower Se supply at earlier stages of fetal development, stimulated homeostatic mechanisms in the offspring that were not initiated by sub-optimal Se. Our observations demonstrate that even moderate Se deficiency during early life negatively may affect, in a sex-specific manner, optimal brain development.

Background: Previous randomized controlled trials examining cognitive and mood effects of combination multivitamin supplements in healthy, non-clinical adults have reported mixed results. One purported explanation for this is that the dietary status of participants at the start of supplement interventions may influence the magnitude of the effect of supplementation. Methods: In this study, we evaluated the effect of a multinutrient formula containing B group vitamins, Bacopa monniera and Ginkgo biloba on memory, attention, mood and biochemical markers of nutrient status in middle-aged adults (M = 52.84 years, n = 141) with ‘optimal’ and ‘sub-optimal’ diets over 12 weeks. We hypothesised that active supplementation would differentially improve memory and attention in those with a ‘sub-optimal’ diet. Results: Mixed model, repeated measures analysis revealed that, in comparison to placebo, active treatment was associated with significant increases in B vitamin status (B1, B6, B12). Regarding behavioural outcomes there was no significant benefit to memory (F(1, 113.51) = 0.53, p = 0.470) nor attention (F(1,113.77) = 1.89, p = 0.171) in the whole cohort. Contrary to our hypothesis, there was a significant beneficial effect of supplementation on attentional performance in individuals with an ‘optimal’ diet prior to supplementation (F(1,57.25) = 4.94, p = 0.030). In the absence of a main effect of supplementation across the entire cohort, there were also a number of significant three-way interactions (treatment by time by diet group) detected in secondary outcomes including lower state anxiety and mental fatigue in those with an ‘optimal’ diet. Conclusion: These findings suggest that the cognitive benefit of B vitamin and herbal supplementation may be dependent on diet quality, supporting the concepts of ‘co-nutrient optimisation’ and interdependency of nutrients. This warrants further investigation. This study advocates characterising the diet of participants prior to supplementation as it may influence the effect of a nutraceutical intervention.

Abstract Objectives Classic selenium (Se) deficiency syndromes are rare in the United States, but individuals with sub-optimal body Se status free of symptoms may be prone to certain chronic diseases such as diabetes if the condition is sustained. In-depth analyses of the National Health and Nutrition Examination Survey estimate that mortality rate is increased when serum Se is < 105.8 μg/L, suggesting that Se status in 10% or 15.5 million Americans aged 40 or older might be sub-optimal. Nonetheless, previous mouse studies show that both dietary selenium deficiency and in excess can promote type 2 diabetes. In this study, we determined the minimally required intake of dietary Se for prevention of type 2 diabetes-like phenotype in mice. Methods Male C57BL/6 J mice at 4 months of age were fed a modified AIN-93 M Se(-) diet containing 24% Torula yeast or the basal diet (0.0072 Se/kg) added with sodium selenate (0.03, 0.06, 0.09, and 0.12 mg Se/kg) for 4 months (n = 6 per group). Glucose tolerance and insulin sensitivity were determined at 5, 6 and 8 months of age. Blood, liver, pancreas and muscle were collected at 8 months of age for biochemical analysis. Results Compared to the Se-adequate diet added with 0.12 mg Se/kg, mice on the Se(-) diet showed increased (P < 0.05) body weight at 7–8 months of age and mice on the Se(-) diet added with 0, 0.03 or 0.06 but not 0.09 mg Se/kg displayed glucose intolerance and insulin resistance in a temporal manner. Results of Western analyses showed that levels of serum glutathione peroxidase 3 and muscle AKT phosphorylation on Ser-473 and Thr-308 were decreased (P < 0.05) in mice on the diets added with 0–0.09 mg Se/kg. Conclusions Collectively, we show that mature mice on Se-insufficient diet at levels lower than 0.09 mg Se/kg for 4 months display sub-optimal body Se status and develop type 2 diabetes-like phenotype. Funding Sources NIH.

Pregnancy represents a stage during which maternal physiology and homeostatic regulation undergo dramatic change and adaptation. The fundamental purpose of these adaptations is to ensure the survival of her offspring through adequate nutrient provision and an environment that is tolerant to the semi-allogenic foetus. While poor maternal diet during pregnancy is associated with perturbed maternal adaptations during pregnancy, the influence of paternal diet on maternal well-being is less clearly defined. We fed C57BL/6 male mice either a control (CD), low protein diet (LPD), a high fat/sugar Western diet (WD) or the LPD or WD supplemented with methyl donors (MD-LPD and MD-WD, respectively) for a minimum of 8 weeks prior to mating with C57BL/6 females. Mated females were culled at day 17 of gestation for the analysis of maternal metabolic, gut, cardiac and bone health. Paternal diet had minimal influences on maternal serum and hepatic metabolite levels or gut microbiota diversity. However, analysis of the maternal hepatic transcriptome revealed distinct profiles of differential gene expression in response to the diet of the father. Paternal LPD and MD-LPD resulted in differential expression of genes associated with lipid metabolism, transcription, ubiquitin conjugation and immunity in dams, while paternal WD and MD-WD modified the expression of genes associated with ubiquitin conjugation and cardiac morphology. Finally, we observed changes in maternal femur length, volume of trabecular bone, trabecular connectivity, volume of the cortical medullar cavity and thickness of the cortical bone in response to the father’s diets. Our current study demonstrates that poor paternal diet at the time of mating can influence the patterns of maternal metabolism and gestation-associated adaptations to her physiology.

Cobweb weaving spiders and their relatives spin multiple task-specific fiber types. The unique material properties of each silk type result from differences in amino acid sequence and structure of their component proteins, primarily spidroins (spider fibrous proteins). Amino acid content and gene expression measurements of spider silks suggest some spiders change expression patterns of individual protein components in response to environmental cues. We quantified mRNA abundance of three spidroin encoding genes involved in prey capture in the common house spider, Parasteatoda tepidariorum (Theridiidae), fed different diets. After 10 days of acclimation to the lab on a diet of mealworms, spiders were split into three groups: (1) individuals were immediately dissected, (2) spiders were fed high-energy crickets, or (3) spiders were fed low-energy flies, for 1 month. All spiders gained mass during the acclimation period and cricket-fed spiders continued to gain mass, while fly-fed spiders either maintained or lost mass. Using quantitative PCR, we found no significant differences in the absolute or relative abundance of dragline gene transcripts, major ampullate spidroin 1 (MaSp1) and major ampullate spidroin 2 (MaSp2), among groups. In contrast, prey-wrapping minor ampullate spidroin (MiSp) gene transcripts were significantly less abundant in fly-fed than lab-acclimated spiders. However, when measured relative to Actin, cricket-fed spiders showed the lowest expression of MiSp. Our results suggest that house spiders are able to maintain silk production, even in the face of a low-quality diet.

The role of mutualistic interactions in adaptive diversification has not been thoroughly examined. Lycaenid butterflies provide excellent systems for exploring mutualistic interactions, as more than half of this family is known to use ants as a resource in interactions that range from parasitism to mutualism. We investigate the hypothesis that protection from predators offered to caterpillars by ants might facilitate host-range evolution. Specifically, experiments with the butterfly Lycaeides melissa investigated the role of ant association in the use of a novel host, alfalfa, Medicago sativa , which is a sub-optimal host for larval development. Survival on alfalfa is increased by the presence of ants, thus supporting the hypothesis that interaction with ants might be important for host-range evolution. Using a demographic model to explore ecological conditions associated with host-range expansion in L. melissa , we conclude that the presence of ants might be an essential component for populations persisting on the novel, sub-optimal host.

In the first of 3 experiments, requirement for total and digestible sulphur amino acids (SAA) was estimated in 240 pigs, 14 to 40 kg. A diet with low digestible amino acids content (digestible sulphur amino acids (SAA) 0.37%) was supplemented with all essential amino acids except methionine and 0, 0.05, 0.1, 0.1 or 0.2% synthetic DL-methionine added, providing diets with 0.42, 0.47, 0.52 and 0.57% digestible SAA. A control diet contained 0.52% digestible SAA. At similar levels of digestible SAA, there was no difference in performance between the experimental and the control diet, showing that optimum performance can be obtained with a less digestible diet supplemented with essential amino acids. Optimum performance was at 0.52% digestible SAA content in the diet, corresponding to about 0.65% total SAA. In experiment 2, 360 pigs 15 to 40 kg, were used to study SAA requirement at sub-optimal (0.60%) and optimal (0.70%) dietary threonine levels. Increasing threonine from 0.60 to 0.70%, increased (P

An experiment utilizing Cobb-500 male broilers was conducted to evaluate the effects of vitamin E (d1--to- copheryl acetate) supplementation at various concentrations (0, 62.5, 125, 250, or 500 mg/kg of diet) on performance and serum concentrations of Triiodothyronine (T₃), Thyroxin (T₄), Adrenocorticotropine Hormone (ACTH), and some metabolites and minerals in broilers reared under heat stress (32°C). One day-old 150 male broilers were randomly assigned to 5 treatment groups, 3 replicates of 10 birds each. The birds received either a basal diet or basal diet supplemented with vitamin E at 62.5, 125, 250, or 500 mg/kg of diet. Increased supplemental vitamin E linearly increased feed intake (P = 0.01), live weight gain (P = 0.01), and improved feed efficiency linearly (P = 0.001). Increasing dietary vitamin E supplementation also resulted in linear increases in serum T₃and T₄ concentrations (P = 0.01) but, linear decreases in ACTH concentration (P = 0.01). Serum glucose, uric acid, triglycerides, and cholesterol concentrations decreased linearly (P = 0.001) while, protein and albumin concentrations increased linearly (P = 0.001) when dietary vitamin E supplementation increased. Serum activities of Serum Glutamic Oxalate Transaminase (SGOT) and Serum Glutamic Pyruvate Transaminase (SGPT) were not influenced by dietary vitamin E supplementation (P > 0.10). However, serum activity of Alkaline Phosphatase (AP) increased linearly (P = 0.001) with increasing dietary vitamin E supplementation. Increasing dietary vitamin E supplementation also caused linear increases (P = 0.001) in serum concentrations of Ca and P. Results of the present study conclude that a 250 mg/kg of vitamin E provides an optimal performance in broiler chicks reared under heat stress, and vitamin E supplementation at such a level can be considered as a protective management practice in a broiler diet, reducing the negative effects of heat stress.

La poule est l'espèce animale d'élevage la plus exploitée dans le monde, et les oeufs, en plus d'avoir des qualités nutritives indéniables, représentent, pour l'homme, la ressource d'origine animale la moins coûteuse. Les industries avicoles s'efforcent d'optimiser leur production, notamment en améliorant l'efficience alimentaire, un caractère important pour assurer la rentabilité des élevages tout en réduisant leur impact environnemental. Ce caractère complexe est sous l'influence de la génétique et de l'environnement, mais de plus en plus d'études confirment également le rôle du microbiote intestinal. Celui-ci participe à la dégradation des aliments et produit de nombreux métabolites qui protègent l'hôte et influencent son métabolisme. Ainsi, plusieurs associations ont été établies entre le microbiote et des caractères de croissance, de santé, de performance et d'efficience alimentaire.Cette thèse propose une analyse du microbiote cæcal de poules pondeuses issues de deux lignées sélectionnées de façon divergente sur leur efficience alimentaire. Le régime alimentaire influençant à la fois l'efficience alimentaire et la composition du microbiote, ces deux lignées ont été nourries avec deux régimes alimentaires, l'un optimal et l'autre réduit en énergie et enrichi en fibres. Pour caractériser les écosystèmes microbiens, trois approches omiques ont été utilisées : le séquençage métabarcoding ciblant le gène de l'ARNr 16S, la métagénomique (séquençage complet des ADN) et la métatranscriptomique (séquençage complet des ARN). Alors que le métabarcoding permet une caractérisation des communautés microbiennes et des fonctions moins résolutive que les deux autres, ces dernières sont plus coûteuses et présentent des défis expérimentaux et méthodologiques importants.Cette thèse a donc eu comme objectifs de répondre à des questions biologiques et méthodologiques : i) identifier le rôle du microbiote cæcal dans l'efficience alimentaire des poules pondeuses, ii) évaluer l'impact du régime alimentaire sur le microbiote et sur son rôle dans l'efficience alimentaire, iii) comparer les différentes approches omiques pour répondre à ces questions.L'analyse de ces données a permis de mettre en évidence des différences de compositions taxonomiques mais également fonctionnelles, à la fois selon la lignée et selon le régime. En outre, les hypothèses du rôle du microbiote dans l'efficience alimentaire des animaux sont conditionnées au régime utilisé pour nourrir les animaux. Elles impliquent notamment des capacités de dégradation de carbohydrates variés (amidon ou fibres indigestes) et aboutissent à une production différenciée d'acides gras à chaîne courte connus pour influencer le métabolisme de l'hôte. Du point de vue de la méthodologie d'analyse, des outils et des stratégies ont été comparés pour mettre en place une chaîne de traitement de ces séquences, tout en mettant en évidence des verrous et des difficultés méthodologiques, nécessitant de futurs développements.Cette thèse apporte de nouveaux éléments sur le rôle du microbiote dans l'efficience alimentaire des poules pondeuses, avec un accent particulier sur ses fonctions métaboliques. Elle souligne également les avantages et les limites des trois techniques omiques utilisées. Des analyses complémentaires sont toutefois nécessaires pour intégrer de façon plus complète les résultats issus de ces différentes approches omiques et pour affiner l'identification des activités microbiennes impliquées
Chickens are the most widely exploited farmed animal species in the world, and eggs, in addition to their undeniable nutritional qualities, represent the least expensive animal-based resource for human consumption. The poultry industry strives to optimize production, in particular by improving feed efficiency, an important factor in ensuring farm profitability while reducing environmental impact. This complex trait is influenced by genetics and the environment, but more and more studies are also confirming the role of the intestinal microbiota. It is involved in the breakdown of food and produces numerous metabolites that protect the host and influence its metabolism. Several associations have been established between the microbiota and growth, health, performance and feed efficiency traits.This thesis presents an analysis of the caecal microbiota of laying hens from two lines divergently selected for feed efficiency. As diet influences both feed efficiency and microbiota composition, these two lines were fed two diets, one optimal and the other reduced in energy and enriched in fiber. To characterize the microbial ecosystems, three omics approaches were used: metabarcoding sequencing targeting the 16S rRNA gene, metagenomics (full DNA sequencing) and metatranscriptomics (full RNA sequencing). While metabarcoding enables less resolutive characterization of microbial communities and functions than the other two, the latter are more costly and present significant experimental and methodological challenges.This thesis therefore aims to answer biological and methodological questions: i) to identify the role of the caecal microbiota in the feed efficiency of laying hens, ii) to assess the impact of diet on the microbiota and its role in feed efficiency, iii) to compare different omics approaches to answer these questions.Analysis of these data revealed differences in taxonomic and functional compositions, both by line and by diet. Furthermore, hypotheses concerning the role of the microbiota in animal feed efficiency are conditioned by the diet used to feed the animals. In particular, they involve the capacity to degrade various carbohydrates (starch or indigestible fibers) and result in the differentiated production of short-chain fatty acids known to influence host metabolism. From a methodology analysis perspective, tools and strategies have been compared to establish a processing chain for these sequences, while highlighting obstacles and difficulties requiring future development.This thesis provides new insights into the role of the microbiota in the feed efficiency of laying hens, with particular emphasis on its metabolic functions. It also highlights the advantages and limitations of the three omics techniques used. Further analysis is needed, however, to integrate the results from these different omics approaches more completely, and to refine the identification of the microbial activities involved

This chapter describes the Healthy Ageing across the Life Course (HALCyon) NDA collaborative research project, the aim of which was to investigate biological and social factors from early life that influence healthy ageing in later life. Healthy ageing was studied as optimal functioning at the individual level, in terms of physical and cognitive capability and wellbeing. The roles of lifetime socioeconomic circumstances, cognitive development and education, body size and diet were investigated, as well as underlying biology (the hypothalamic-pituitary-adrenal (HPA) axis, telomeres and genes). The project undertook: systematic reviews and meta-analyses of all available studies; comparative analysis using harmomised data across nine British cohort studies; in depth analysis of single cohorts with unique data; and qualitative interviews with sub-samples of participants from three of these cohorts.

Abstract Of the five large carnivores in the Kruger National Park, spotted hyaenas have the widest diet, eating more non-mammal food items than the others. They also scavenge more than the others, about half the biomass of food they consume. The diets of lions, leopards, cheetahs and African wild dogs overlap strikingly with regard to medium-sized and small mammals, particularly impala. Lions removed over 50% of the biomass of prey killed by the large predators in the main study area, having a particularly heavy influence on the wildebeest population. They may also deprive the smaller predators of impala. Hyaenas scavenged a substantial amount of food from lions, but only after the lions had finished eating. Hyaenas chased cheetahs off 14% of their kills, but were not seen to steal food from wild dogs. Lions were observed to kill wild dogs. Hyaenas and lions showed a preference for thickets and plains, leopards for thickets, hills and river banks, cheetahs for plains and wild dogs for thickets and hills. Impala had their highest preference ratio for thickets, followed by hills and plains. Hyaenas, lions and leopards are predominantly nocturnal, wild dogs are crepuscular and cheetahs kill mainly during the middle of the day. The large number of resident prey in the system favours lions and hyaenas. Leopards, with a wide diet and the ability to utilize habitats not favoured by most of the others, outnumber cheetahs and wild dogs. Cheetahs have to cope with sub optimal hunting conditions and pressure from spotted hyaenas. It is unclear why wild dogs, which are such efficient hunters in this area, are not more abundant.

Growth performance of broiler chickens may be sub-optimal because starch is digested too rapidly and protein too slowly. This chapter reviews how a better understanding of digestive kinetics can address this challenge and contribute to least-cost formulation of broiler diets to enhance chicken-meat production. It begins by reviewing the process of protein and starch digestion. The chapter then reviews factors affecting digestion such as the speed of protein digestion and amino acid absorption, the more rapid intestinal uptake of non-bound methionine, as well as the role of slowly-digestible starch in promoting broiler growth performance. The chapter shows that accounting for these factors can significantly improve the efficiency of broiler diets.

In current and next-generation semiconductor electronic devices, sub-continuum heat transfer effects and non-uniform power distribution across the die surface lead to large temperature gradients and localized hot spots on the die. These hot spots can adversely affect device performance and reliability. In this work, we propose an enhanced method for thermal map prediction that considers sub-continuum thermal transport effects and show their impact in floor plan optimization. Sub-continuum effects are expressed in terms of an effective thermal conductivity. We introduce and calibrate a 2D thermal model of the die for fast simulation of thermal effects under non-uniform power generation scenarios. The calibrated 2D model is then used to study the impact of the effective thermal conductivity on the thermal map prediction and floor plan optimization. Results show that sub-continuum effects radically change both the predicted thermal performance and the optimal floor plan configurations.