Carbohydrate Ratio Research Articles

Effects of yeast culture supplementation and the ratio of non-structural carbohydrate to fat on growth performance, carcass traits and the fatty acid profile of the longissimus dorsi muscle in lambs.

The effects of yeast culture (YC) supplementation and the dietary ratio of non-structural carbohydrate to fat (NSCFR) on growth performance, carcass traits and fatty acid profile of the longissimus dorsi (LD) muscle in lambs were determined in a 2×3 full factorial experiment. Thirty-six Small-tailed Han lambs were randomly divided into six groups with six replicates per group. The lambs were fed one of the six pelleted total mixed rations (TMRs) for 60days after 15 adaption days. The six rations were formed by two NSCFRs (11.37 and 4.57) and three YC supplementation levels (0, 0.8 and 2.3g/kg dietary dry matter). The average daily gain (ADG), dry matter intake (DMI) and feed conversion ratio (FCR) data of each lamb were recorded and calculated. All the lambs were slaughtered for determining carcass traits and fatty acid profile of the LD muscle. DMI was significantly increased (p<0.05) in a quadratic fashion with 0.8g/kg of YC supplementation. Carcass weight (CW) and dressing percentage (DP) were significantly increased (p<0.05) in a linear fashion with 2.3g/kg of YC supplementation. Animals fed with high-NSCFR diet had higher (p<0.05) contents of myristoleic acid (C14:1), pentadecanoic acid (C15:0) and cis-10-heptadecenoic acid (C17:1), and lower (p<0.05) stearic acid (C18:0) content in LD muscle than those fed with low-NSCFR diet. Moreover, ADG, growth rate (GR), backfat thickness (BFT), percentages of crude fat (CF) and crude protein (CP), SFAs, MUFAs and PUFAs in LD muscle, were significantly affected (p<0.05) by interaction of dietary NSCFR and supplemental YC level. Overall, YC not only improved the growth performance and carcass traits of the animals but also modified the fatty acid profile of the LD muscle. Furthermore, the effects of YC supplementation may depend on dietary compositions.

First evidence of protein-carbohydrate regulation in a plant bug (Lygus hesperus)

Lygus bugs are highly polyphagous piercing/sucking insects found throughout North America. Collectively, they have been reported to feed on over 330 plant species (one of the broadest host range ever documented for a group of insects); they also feed on many economically important crops. Despite its prevalence across North America and status as a common pest in many agroecosystems, very little is known about how Lygus bugs regulate their intake of nutrients. In reality, little is known about nutrient regulation for most hemipterans, specifically non-phloem feeding species in the suborder Heteroptera. This likely reflects difficulties in developing adequate artificial diets for insects with piercing/sucking mouthparts. There is, however, an artificial diet for L. hersperus, and in this study we modified it and performed choice and no-choice experiments to determine how L. hesperus regulates its intake of two macronutrients – protein (p) and carbohydrates (c) – that are tightly linked to survival and performance in other insect herbivores. In choice experiments L. hesperus was allowed to select between two foods with different protein:carbohydrate ratios. We documented strong regulation for protein and carbohydrates, with late instar nymphs selecting a slightly protein-biased intake target (protein-carbohydrate ratio = 1.5:1). We also performed no-choice experiments, where nymphs were restricted to a single food. Here, the protein-carbohydrate ratio of their food had a strong impact on survival, which was highest for nymphs reared on the treatment with a protein-carbohydrate ratio closest to the self-selected intake target (determined by the choice experiments), but no significant impact on developmental time or mass gain. Our data are the first of their kind for a non-phloem feeding hemipteran and provide a starting point for more broadly understanding and further investigating the nutritional ecology/physiology of Lygus bugs. Our study also provides a framework for exploring nutrient regulation in other hemipterans and for optimizing artificial diets for piercing/sucking insects, especially heteropterans.

Improvement of energy substrate metabolism by late evening snack supplementation in patients with liver cirrhosis: a meta-analysis.

Aim: Malnutrition is one of the most common complications in patients with liver cirrhosis. Abnormal energy substrate metabolism may contribute to aggravation of malnutrition. Late evening snack (LESs) supplementation has been recommended as an intervention to reduce starvation time and improve nutritional status. Published studies have analyzed the effect of LESs on the branched-chain amino acid (BCAA)/tyrosine ratio (BTR) and oxidation rate of fat and carbohydrate in patients with liver cirrhosis.Methods: We searched PubMed, Cochrane Library, Web of Science and Embase for relevant research from January 2000 to October 2018. The primary outcome for this analysis was changes in BTR and fat and carbohydrate oxidation in patients with liver cirrhosis.Results: A total of 9 articles, containing 211 patients, were included in this analysis. The results supported that supplementation with BCAA-enriched LESs improved BTR, and long-term supplementation with BCAAs (>1 month) may be more beneficial than short-term supplementation (<1 month) in patients with liver cirrhosis. In addition, supplementation with BCAAs may increase the oxidation rate of carbohydrates and decrease the oxidation rate of fat. Furthermore, compared with liquid-enriched LESs, BCAA was a better choice for increasing the oxidation of carbohydrates and decreasing the rate of fat oxidation.Conclusion: BCAA-enriched LES supplementation is an appropriate nutritional intervention to improve abnormal energy substrate metabolism, which may improve malnutrition in patients with liver cirrhosis. Further research is needed on the long-term benefit and improved survival in patients with liver cirrhosis.

Spatial and temporal changes of mineral nutrients and carbohydrates in cuttings of four stone fruit rootstocks and their contribution to rooting potential

Hardwood cuttings of four stone fruit rootstocks (Cadaman, Rootpac-R, GF677 and Myrobalan 29C) were used as planting material to induce rooting in a bottom-heated cold frame. Cuttings were taken during four successive months from the basal, middle and apical part of the current seasons shoot. Carbohydrates and mineral nutrients were analyzed in the bases of the cuttings right before auxin application (before their placement in the frame), in order to assess any relation with the rooting capacity of the cuttings. Rootpac-R and Myrobalan 29C proved to be quite easy to root (reaching almost 90% rooted cuttings), followed by GF677 and lastly by Cadaman, which was the most recalcitrant rootstock to root by hardwood cuttings. Rootstocks were clearly distinguished by Principal Components Analysis and discriminant analysis, based on the measured parameters. Cuttings’ bases of the difficult to root Cadaman were characterized by high carbohydrate and nitrogen concentration, but relatively low ratio (carbohydrates versus nitrogen) while the opposite was found in the bases of the easy to root Rootpac-R. The latter was characterized along with Myrobalan 29C by high boron and manganese concentrations. It was clear that carbohydrate concentration does not have a major role in the rooting potential of the cuttings of the four rootstocks used in this study, while the ratio of carbohydrates versus nitrogen may have a more crucial role. Cuttings from the basal and middle part of the shoot rooted in higher percentages than those form the apical part, while November and December were in most cases the preferred months to take cuttings. Furthermore, a hypothesis is described based on the concentration of boron and manganese, on their possible role in regulating (directly or indirectly) the activity of IAA oxidase enzyme, at a time when high endogenous IAA is not desirable.

Life cycle assessment of diets for gilthead seabream (Sparus aurata) with different protein/carbohydrate ratios and fishmeal or plant feedstuffs as main protein sources

PURPOSE: Aquaculture is the best alternative to fulfil global fish demand, however it still relies heavily on fisheries-derived products for aquafeeds production. This study assesses and compares the environmental impacts of producing four experimental diets to gilthead seabream with different dietary protein (P) to carbohydrate (CH) ratios (P50/CH10 and P40/CH20). The diets were made either with fish meal (FM) or plant feedstuffs (PF) as main protein sources and fish oil (FO) or vegetable oils (VO) as lipid sources. METHODS: The functional unit used was 1 kg of experimental diet. The studied boundaries included aquafeed ingredients production (S1), compound aquafeeds production under laboratory conditions (S2), and transportation between S1 and S2 locations. The present study applied the Recipe Endpoint method, hierarchist version (V1.13; Europe recipe H/A). Background data was collected from ecoinvent database and related literature. For each aquafeed ingredient used, it was accounted either the agriculture production or fishery activities, the processing unit, and transportation between the production and processing locations. Ingredient mixing and processing was done at the Marine Zoology Station (MZS) located at Porto, Portugal. It was also taken into account the road transportation of aquafeed ingredients between a commercial company and the MZS. RESULTS AND DISCUSSION: Regardless of dietary protein source or P/CH ratio used, all diets had the same single score index. In agreement with several studies, S1 was the system with the highest environmental impact. On the other hand, S2 was the lowest environmental contributor step to all formulated diets, except for diet P50/CH10, where the lowest environmental impact was related with the aquafeed ingredients transportation to MZS. Fisheries-derived ingredients were the biggest contributors to environmental impact. In the hypothesis of replacing FO from Portuguese fisheries by-products by FO of Peruvian anchovy fisheries or by soybean oil (SBO), the environmental impact of the diets would be decreased, being the replacement by SBO the best environmental alternative. CONCLUSIONS: There was highlighted a tendency for PF-based diets having lower environmental impact score when compared to the FM-based diets after both hypothetical replacements. Studying the replacement of by-products FO by Peruvian anchovy FO or by SBO allowed to emphasize the importance of adequate ingredients selection for reducing the environmental impact. As limitations of the current study it is important to mention: the use of pelletization as manufacturing process and the non-valorization of fish by-products as recycled aquafeed ingredients.

Dietary Macronutrient Management to Treat Mitochondrial Dysfunction in Parkinson's Disease.

Mitochondrial dysfunction has been demonstrated to play an important role in the pathogenesis of Parkinson’s disease (PD). The products of several PD-associated genes, including alpha-synuclein, parkin, pink1, protein deglycase DJ-1, and leucine rich repeat kinase 2, have important roles in mitochondrial biology. Thus, modifying mitochondrial function could be a potential therapeutic strategy for PD. Dietary management can alter mitochondrial function as shifts in dietary macronutrients and their ratios in food can alter mitochondrial energy metabolism, morphology and dynamics. Our studies have established that a low protein to carbohydrate (P:C) ratio can increase lifespan, motor ability and mitochondrial function in a parkin mutant Drosophila model of PD. In this review, we describe mitochondrial dysfunction in PD patients and models, and dietary macronutrient management strategies to reverse it. We focus on the effects of protein, carbohydrate, fatty acids, and their dietary ratios. In addition, we propose potential mechanisms that can improve mitochondrial function and thus reverse or delay the onset of PD.

Spatial variation in the biochemical and isotopic composition of corals during bleaching and recovery.

Ocean warming and the increased prevalence of coral bleaching events threaten coral reefs. However, the biology of corals during and following bleaching events under field conditions is poorly understood. We examined bleaching and postbleaching recovery in Montipora capitata and Porites compressa corals that either bleached or did not bleach during a 2014 bleaching event at three reef locations in Kāne‘ohe Bay, O‘ahu, Hawai‘i. We measured changes in chlorophylls, tissue biomass, and nutritional plasticity using stable isotopes (δ 13C, δ 15N). Coral traits showed significant variation among periods, sites, bleaching conditions, and their interactions. Bleached colonies of both species had lower chlorophyll and total biomass, and while M. capitata chlorophyll and biomass recovered 3 months later, P. compressa chlorophyll recovery was location dependent and total biomass of previously bleached colonies remained low. Biomass energy reserves were not affected by bleaching, instead M. capitata proteins and P. compressa biomass energy and lipids declined over time and P. compressa lipids were site specific during bleaching recovery. Stable isotope analyses did not indicate increased heterotrophic nutrition in bleached colonies of either species, during or after thermal stress. Instead, mass balance calculations revealed that variations in δ 13C values reflect biomass compositional change (i.e., protein : lipid : carbohydrate ratios). Observed δ 15N values reflected spatiotemporal variability in nitrogen sources in both species and bleaching effects on symbiont nitrogen demand in P. compressa. These results highlight the dynamic responses of corals to natural bleaching and recovery and identify the need to consider the influence of biomass composition in the interpretation of isotopic values in corals.

HYGIENIC CHARACTERISTICS OF NUTRITION OF CONVICTS SERVING SENTENCES IN PENAL COLONIES IN THE TERRITORY OF THE REPUBLIC OF TATARSTAN

The issues of nutrition of convicts, for years of existence of the Soviet Union and currently, are not studied completely. Citizens detained in penitentiary institutions (PI) have specific socio-demographic characteristics. Along with the unsatisfactory sanitary conditions for convicts in the colonies, the hygienic assessment of their nutrition becomes important. Without proper hygienic evaluation of food it is impossible to develop effective interventions to improve their health. Taking this into account, the article shows the hygienic assessment of the actual nutrition of convicts over the period of 2009-2012, according to 320 menu layouts accepted by the Order Ministry of Justice of Russia, No. 125, August, 2005. There are presented data on caloric value of diets of persons sentenced to imprisonment in penal colonies in the Republic of Tatarstan, provision of the body by proteins, fats, carbohydrates, vitamins, minerals such as calcium, phosphorus, magnesium. There is given the analysis of the ratio of proteins, fats and carbohydrates in the diet of prisoners, as well as calcium and phosphorus.

A Clinical Training Program for Hybrid Closed Loop Therapy in a Pediatric Diabetes Clinic.

Hybrid closed loop (HCL) therapy is now available in clinical practice for treatment of type 1 diabetes; however, there is limited research on how to educate patients on this new therapy. The purpose of this quality improvement project was to optimize a HCL education program for pediatric patients with type 1 diabetes (T1D). Our multidisciplinary team developed a novel HCL clinical training program for current insulin pump users, using a quality improvement process called the Plan-Do-Study-Act model. Seventy-two patients participated in the HCL training program, which included (1) an in-person group class to reinforce conventional insulin pump and CGM use on the new system, (2) a live video conference class to teach HCL use, and (3) three follow-up phone calls in the first 4 weeks after HCL training to assess system use, make insulin adjustments, and provide targeted reeducation. Diabetes educators collected data during follow-up calls, and patients completed a training satisfaction survey. The quality improvement process resulted in a training program that emphasized education on HCL exits, CGM use, and optimizing insulin to carbohydrate ratio settings. Patients successfully sustained time in HCL in the initial weeks of use and rated the trainings and follow-up calls highly. Ongoing educational support is vital in the early weeks of HCL use. This quality improvement project is the first to examine strategies for implementation of HCL therapy into a large pediatric diabetes center, and may inform best practices for implementation of new diabetes technologies into other diabetes clinics.

Experimental warming reduced topsoil carbon content and increased soil bacterial diversity in a subtropical planted forest

The potential effects of global warming on the soil carbon (C) dynamics of subtropical forests are uncertain. To assess the effects of warming on soil C and tree roots, combined soil warming (infrared heaters, +1.5 °C soil temperature) and trenching experiments were conducted in a subtropical Castanopsis hystrix plantation. Topsoil C content was reassessed after five years of warming, and the effects on soil organic carbon (SOC) quality and microbial diversity were analyzed. Compared with corresponding controls, the topsoil (0–10 cm) SOC content was significantly lower in un-trenched warmed soil (−13.6%) as well as in trenched warmed soil (−15.4%). However, the range of SOC content after five years of warming was similar to that observed after two years of warming (−14.6%, −19.2%), indicating that the warming effect on SOC content had leveled off during the latter three years of the study. In trenched plots, warming significantly decreased the carbohydrate C as well as the ratio of carbohydrate C to N-alkyl/methoxyl C (CC/MC), suggesting that labile C was preferentially decomposed. In un-trenched plots, SOC quality was unaffected, indicating a compensatory input of labile root C. Bacterial α-diversity increased under warming, whereas no significant warming effects on fungal community diversity were observed. Both the SOC content and the proportion of soil carbohydrate C were negatively correlated with soil bacterial α-diversity, suggesting that the abundance of more recalcitrant SOC increased soil microbial diversity. Overall, our study indicates that soil warming leads to moderate initial reductions in topsoil SOC in the studied forest ecosystem. This is consistent with recent evidence that low SOC-containing soils (e.g., subtropical forest soils) exhibit a weaker response to soil warming than high SOC-containing soils.

Pck-ing up steam: Widening the salmonid gluconeogenic gene duplication trail

Rainbow trout have, as salmonid fish species, undergone sequential genome duplication events in their evolutionary history. In addition to a teleost-specific whole genome duplication approximately 320–350 million years ago, rainbow trout and salmonids in general underwent an additional salmonid lineage-specific genome duplication event approximately 80 million years ago. Through the recent sequencing of salmonid genome sequences, including the rainbow trout, the identification and study of duplicated genes has become available. A particular focus of interest has been the evolution and regulation of rainbow trout gluconeogenic genes, as recent molecular and gene expression evidence points to a possible contribution of previously uncharacterized gluconeogenic gene paralogues to the rainbow trout long-studied glucose intolerant phenotype. Since the publication of the initial rainbow trout genome draft, resequencing and annotation have further improved genome coverage. Taking advantage of these recent improvements, we here identify a salmonid-specific genome duplication of ancestral mitochondrial phosphoenolpyruvate carboxykinase 2 isoenzyme, we termed pck2a and pck2b. Cytosolic phosphoenolpyruvate carboxykinase (Pck1) and, more recently mitochondrial Pck2, are considered to be the rate-limiting enzymes in de novo gluconeogenesis. Following in silico confirmation of salmonid pck2a and pck2b evolutionary history, we simultaneously profiled cytosolic pck1 and mitochondrial pck2a and pck2b expression in rainbow trout liver under several experimental conditions known to regulate hepatic gluconeogenesis. Cytosolic pck1 abundance was increased by nutritional (diets with a high protein to carbohydrate ratio compared to diets with a low carbohydrate to protein ratio) and glucoregulatory endocrine factors (glucagon and cortisol), revealing that the well-described transcriptional regulation of pck1 in mammals is present in rainbow trout. Conversely, and in contrast to mammals, we here describe endocrine regulation of pck2a (decrease in abundance in response to glucagon infusion), and nutritional, social-status-dependent and hypoxia-dependent regulation of pck2b. Specifically, pck2b transcript abundance increased in trout fed a diet with a low protein to carbohydrate ratio compared to a diet with a high protein to carbohydrate ratio, in dominant fish compared to subordinate fish as well as hypoxia. This specific and differential expression of rainbow trout pck2 ohnologues is indicative of functional diversification, and possible functional consequences are discussed in light of the recently highlighted gluconeogenic roles of mitochondrial pck2 in mammalian models.

Effects of yeast culture supplementation and the ratio of non-structural carbohydrate to fat on rumen fermentation parameters and bacterial-community composition in sheep

This study aimed to evaluate the effects of yeast culture (YC) supplementation and the ratio of non-structural carbohydrate to fat (NSCFR) on rumen fermentation parameters (RFPs) and bacterial-community composition (BCC) using 6 ruminally cannulated sheep in a 2 × 3 factorial experiment. We formulated 6 dietary treatments with 3 levels of YC supplementation (0, 0.8 and 2.3 g/kg of dietary dry matter) and 2 dietary NSCFRs (17.02 and 5.60). Each animal was fed 1 of 6 diets in a 6 × 6 Latin square arrangement during the experiment. Ruminal liquid was sampled at 0, 2, 4, 6, 8, and 12 h after morning feeding on days 16 and 17 (last 2 days) in all 6 of the Latin square periods. The concentrations of acetic acid, butyric acid and total volatile fatty acid (TVFA) were significantly (p < 0.05) increased and the pH values were significantly (p < 0.05) decreased when the animals fed on high-NSCFR diet (H diet) with 2.3 g/kg of YC at 2 h after feeding compared with that on the low-NSCFR diet (L diet). However, the concentrations of ammonia nitrogen (NH3-N) were higher (p < 0.05) in all H groups than that in L groups. The relative abundances of Prevotella_1 were higher in all L groups (p < 0.05), while Lachnospiraceae_NK3A20 and Olsenella were higher in H groups (p < 0.05). Compared with L groups, the relative abundances of Candidatus_Saccharimonas and [Ruminococcus]_gauvreauii of H groups were increased when supplemented with YC (2.3 g/kg; p < 0.05). A significant increased relative abundance of Butyrivibrio_2 was observed in the L group (2.3 g/kg YC). Overall, the RFPs and BCC were influenced by both dietary NSCFR and YC supplementation. There was significant interaction between dietary NSCFR and YC supplementation in the aspects of VFAs, NH3-N and all genera of BCC.

Interactions among morphotype, nutrition, and temperature impact fitness of an invasive fly.

Invasive animals depend on finding a balanced nutritional intake to colonize, survive, and reproduce in new environments. This can be especially challenging during situations of fluctuating cold temperatures and food scarcity, but phenotypic plasticity may offer an adaptive advantage during these periods. We examined how lifespan, fecundity, pre‐oviposition periods, and body nutrient contents were affected by dietary protein and carbohydrate (P:C) ratios at variable low temperatures in two morphs (winter morphs WM and summer morphs SM) of an invasive fly, Drosophila suzukii. The experimental conditions simulated early spring after overwintering and autumn, crucial periods for survival. At lower temperatures, post‐overwintering WM lived longer on carbohydrate‐only diets and had higher fecundity on low‐protein diets, but there was no difference in lifespan or fecundity among diets for SM. As temperatures increased, low‐protein diets resulted in higher fecundity without compromising lifespan, while high‐protein diets reduced lifespan and fecundity for both WM and SM. Both SM and WM receiving high‐protein diets had lower sugar, lipid, and glycogen (but similar protein) body contents compared to flies receiving low‐protein and carbohydrate‐only diets. This suggests that flies spend energy excreting excess dietary protein, thereby affecting lifespan and fecundity. Despite having to recover from nutrient depletion after an overwintering period, WM exhibited longer lifespan and higher fecundity than SM in favorable diets and temperatures. WM exposed to favorable low‐protein diet had higher body sugar, lipid, and protein body contents than SM, which is possibly linked to better performance. Although protein is essential for oogenesis, WM and SM flies receiving low‐protein diets did not have shorter pre‐oviposition periods compared to flies on carbohydrate‐only diets. Finding adequate carbohydrate sources to compensate protein intake is essential for the successful persistence of D. suzukii WM and SM populations during suboptimal temperatures.

USE OF STARCH SYRUPS IN THE PRODUCTION OF JELLY

In the presented work the choice of starch syrup for the jelly products production has been substantiated. It was based on the analysis of the starch syrup carbohydrate profiles and recipes of jelly products. The influence of syrup on the rheological and structural-mechanical properties of jelly and aerated masses for a two-layer jelly has been determined. The expediency of polydextrose usage has been demonstrated. Its adding leads to the regulation of the jelly structure and foam layer for the samples with more than 50% of sugar replaced by starch syrup. Depending on the ratio of carbohydrates in jelly it was determined the amount of polydextrose adding of which provides the required firming and prebiotic properties of finish products. The change of physical-chemical, structural-mechanical, and organoleptic quality indices of two-layer jelly with modified carbohydrate composition has been investigated during storage.

Hygienic features of the diet of foreign medical students considering their national cultures

During studying, foreign students undergo many stages of adaptation to new habitats, including adaptations to climatic, social and nutritional features in Ukraine. Foreign students experience difficulties in shaping their diet, following national traditions. They do not always have the right to pick analogues of the usual food products, to cook, and are increasingly fed in fast food. The aim of the study is to offer corrective measures on the diet of foreign medical students, taking into account the characteristics of national cultures, which depend on the geographical location of the country of residence of students. To achieve the goal, the following objectives were set: to assess the peculiarities of the diet of students who came from Africa and South Asia from gender perspective; to identify factors that prevent foreign medical students from following the principles of rational nutrition; to develop proposals for correction of eating behavior of students. Methods of research - sociological (questioning and interviewing), analytical, medical-statistical, nonparametric methods of mathematical statistics. The paper presents data on the quantitative and qualitative composition of food products that respondents used during the day and the diet of foreign medical students who came to study from the countries of Africa and South Asia. It has been established that nutrition of students is not balanced in structure, mode, protein, fat, carbohydrate ratio in both groups. The author shows the main barriers that, according to students, impede them to eat rationally. Obtaining data allowed to make recommendations for the correction of eating behavior by foreign students, which consists in conducting information companies among foreign students for the promotion of healthy eating, taking into account the data of a permanent residence; informing the students about WHO recommendations for healthy eating; conducting constant monitoring of eating behavior of students using the proposed questionnaire.

Metabolic responses to dietary carbohydrate/lipids ratios in neotropical hybrid catfish (♂Pseudoplatystoma corruscans×♀Pseudoplatystoma fasciatum).

The purpose of this study was to assess the effect of different carbohydrate and lipid (CHO/L) ratios on the performance and energy metabolism of hybrid catfish (♂Pseudoplatystoma corruscans × ♀ Pseudoplatystoma fasciatum). One hundred and sixty-eight fish (104.9±16.5 g BW) were distributed into 24 100-L tanks. The experiment was performed using a randomised block design with four CHO/L ratios (0.45, 1.00, 1.66 and 2.85) and six replications. Growth performance, protein content, glucose and triglycerides in plasma, muscle and liver, and the hepatic activity of the malic and glucose-6-phosphate dehydrogenase (G6PD) enzymes were measured after 60 feeding days. No significant differences were observed in growth performance, protein and triglycerides of plasma and muscle, hepatic protein or malic enzyme activity. CHO/L: 2.85 provided the highest plasma and liver glucose, while CHO/L: 0.45 showed high liver triglycerides. A linear effect was found for the hepatic activity of G6PD and dietary starch levels (R2=0.93). The hepatic activity of G6PD was greater in CHO/L=2.85 than for CHO/L: 0.45. In conclusion, the limit of dietary starch inclusion and lipids were 15% and 9.00%, respectively (CHO/L: 1.66), and this level did not affect the energy metabolism of the juvenile hybrid catfish.

Dietary Proteins, Brown Fat, and Adiposity.

High protein diets have become popular for body weight maintenance and weight loss despite controversies regarding efficacy and safety. Although both weight gain and weight loss are determined by energy consumption and expenditure, data from rodent trials consistently demonstrate that the protein:carbohydrate ratio in high fat diets strongly influences body and fat mass gain per calorie eaten. Here, we review data from rodent trials examining how high protein diets may modulate energy metabolism and the mechanisms by which energy may be dissipated. We discuss the possible role of activating brown and so-called beige/BRITE adipocytes including non-canonical UCP1-independent thermogenesis and futile cycles, where two opposing metabolic pathways are operating simultaneously. We further review data on how the gut microbiota may affect energy expenditure. Results from human and rodent trials demonstrate that human trials are less consistent than rodent trials, where casein is used almost exclusively as the protein source. The lack of consistency in results from human trials may relate to the specific design of human trials, the possible distinct impact of different protein sources, and/or the differences in the efficiency of high protein diets to attenuate obesity development in lean subjects vs. promoting weight loss in obese subjects.

Gender and Age Stratified Analyses of Nutrient and Dietary Pattern Associations with Circulating Lipid Levels Identify Novel Gender and Age-Specific Correlations.

Dyslipidemia is a precursor to a myriad of cardiovascular diseases in the modern world. Age, gender, and diet are known modifiers of lipid levels, however they are not frequently investigated in subset analyses. Food and nutrient intakes from National Health and Nutrition Examination Study 2001–2013 were used to assess the correlation between lipid levels (high-density lipoprotein (HDL) cholesterol, triglycerides (TG), low-density lipoprotein (LDL) cholesterol, and total cholesterol (TC):HDL cholesterol ratio) and nutritional intake using linear regression. Associations were initially stratified by gender and significant gender correlations were further stratified by age. Analyses were performed at both the dietary pattern and nutrient level. Dietary pattern and fat intake correlations agreed with the literature in direction and did not demonstrate gender or age effects; however, we observed gender and age interactions among other dietary patterns and individual nutrients. These effects were independent of ethnicity, caloric intake, socioeconomic status, and physical activity. Elevated HDL cholesterol levels correlated with increasing vitamin and mineral intake in females of child bearing age but not males or older females (≥65 years). Moreover, increases in magnesium and retinol intake correlated with HDL cholesterol improvement only in females (all age groups) and males (35–64), respectively. Finally, a large amount of gender-specific variation was associated with TG levels. Females demonstrated positive associations with sugar and carbohydrate while males show inverse associations with polyunsaturated fatty acid (PUFA) intake. The female-specific association increased with the ratio of carbohydrate: saturated fatty acid (SFA) intake, suggesting that gender specific dietary habits may underlie the observed TG-nutrient correlations. Our study provides evidence that a subset of previously established nutrient-lipid associations may be gender or age-specific. Such discoveries provide potential new avenues for further research into personalized nutritional approaches to treat dyslipidemia.

Genotype to phenotype: Diet-by-mitochondrial DNA haplotype interactions drive metabolic flexibility and organismal fitness.

Diet may be modified seasonally or by biogeographic, demographic or cultural shifts. It can differentially influence mitochondrial bioenergetics, retrograde signalling to the nuclear genome, and anterograde signalling to mitochondria. All these interactions have the potential to alter the frequencies of mtDNA haplotypes (mitotypes) in nature and may impact human health. In a model laboratory system, we fed four diets varying in Protein: Carbohydrate (P:C) ratio (1:2, 1:4, 1:8 and 1:16 P:C) to four homoplasmic Drosophila melanogaster mitotypes (nuclear genome standardised) and assayed their frequency in population cages. When fed a high protein 1:2 P:C diet, the frequency of flies harbouring Alstonville mtDNA increased. In contrast, when fed the high carbohydrate 1:16 P:C food the incidence of flies harbouring Dahomey mtDNA increased. This result, driven by differences in larval development, was generalisable to the replacement of the laboratory diet with fruits having high and low P:C ratios, perturbation of the nuclear genome and changes to the microbiome. Structural modelling and cellular assays suggested a V161L mutation in the ND4 subunit of complex I of Dahomey mtDNA was mildly deleterious, reduced mitochondrial functions, increased oxidative stress and resulted in an increase in larval development time on the 1:2 P:C diet. The 1:16 P:C diet triggered a cascade of changes in both mitotypes. In Dahomey larvae, increased feeding fuelled increased β-oxidation and the partial bypass of the complex I mutation. Conversely, Alstonville larvae upregulated genes involved with oxidative phosphorylation, increased glycogen metabolism and they were more physically active. We hypothesise that the increased physical activity diverted energy from growth and cell division and thereby slowed development. These data further question the use of mtDNA as an assumed neutral marker in evolutionary and population genetic studies. Moreover, if humans respond similarly, we posit that individuals with specific mtDNA variations may differentially metabolise carbohydrates, which has implications for a variety of diseases including cardiovascular disease, obesity, and perhaps Parkinson’s Disease.

Survival and Fecundity Parameters of Two Drosophila suzukii (Diptera: Drosophilidae) Morphs on Variable Diet Under Suboptimal Temperatures.

Life history parameters are used to estimate population dynamics, mortality, and reproduction in insects relative to their surrounding environment. For Drosophila suzukii Matsumura (Diptera: Drosophilidae), an invasive agricultural pest, previous studies have estimated net reproductive rate (Ro), generation time (T), and intrinsic rate of population increase (rm). A main limitation is that these estimates were measured under relatively favorable settings, and do not reflect environmental conditions and physiological states encountered during dormancy periods. Therefore, this study investigated the impacts of 1) low temperatures and 2) dietary protein: carbohydrate ratios (P:C) on both survival and fecundity parameters of D. suzukii summer morphs (SM) and postoverwintering winter morphs (WM) over physiological age (degree-days, DD). In both morphs, reproductive rates were higher and lifespan was longer when flies were exposed to low protein (P:C 1:4) or carbohydrate-only diets (P:C 0:1) compared with high protein diets (P:C 1:1). WM had higher reproductive rates and longer generation times than SM on optimal 1:4 diet in all trialed temperatures, but at the lowest temperatures, SM had higher reproductive rates than WM in carbohydrate-only and high protein diets. This likely reflected delayed oogenesis and hindered reproduction after an overwintering period in WM receiving suboptimal diets. Oviposition for SM and WM receiving 1:4 diet commenced from 0 to 100 DD, and peaked between 400 and 500 DD, earlier than flies receiving 0:1 diet. These results suggest that dietary protein has a crucial role in early oogenesis, particularly for postoverwintering WM. The parameters developed here reflect the population dynamics of D. suzukii before and after the crop growing season, an essential time for population buildup, survival, and early and late host infestation.