Diet Period Research Articles

Short-term exposure to an obesogenic diet causes dynamic dysregulation of proteasome-mediated protein degradation in the hypothalamus of female rats

ABSTRACT Objectives Previous work has shown that exposure to a high fat diet dysregulates the protein degradation process in the hypothalamus of male rodents. However, whether this occurs in a sex-independent manner is unknown. The objective of this study was to determine the effects of a short-term obesogenic diet on the ubiquitin-proteasome mediated protein degradation process in the hypothalamus of female rats. Methods We fed young adult female rats a high fat diet or standard rat chow for 7 weeks. At the end of the 7th week, animals were euthanized and hypothalamus nuclear and cytoplasmic fractions were collected. Proteasome activity and degradation-specific (K48) ubiquitin signaling were assessed. Additionally, we transfected female rats with CRISPR-dCas9-VP64 plasmids in the hypothalamus prior to exposure to the high fat diet in order to increase proteasome activity and determine the role of reduced proteasome function on weight gain from the obesogenic diet. Results We found that across the diet period, females gained weight significantly faster on the high fat diet than controls and showed dynamic downregulation of proteasome activity, decreases in proteasome subunit expression and an accumulation of degradation-specific K48 polyubiquitinated proteins in the hypothalamus. Notably, while our CRISPR-dCas9 manipulation was able to selectively increase some forms of proteasome activity, it was unable to prevent diet-induced proteasome downregulation or abnormal weight gain. Conclusions Collectively, these results reveal that acute exposure to an obesogenic diet causes reductions in the protein degradation process in the hypothalamus of females.

Oral and Injected Tamoxifen Alter Adult Hippocampal Neurogenesis in Female and Male Mice.

Inducible Cre recombinase facilitates temporal control of genetic recombination in numerous transgenic model systems, a feature which has made it a popular tool for adult neurogenesis studies. One of the most common forms of inducible Cre, CreERT2, requires activation by the selective estrogen receptor modulator tamoxifen (TAM) to initiate recombination of LoxP-flanked sequences. To date, most studies deliver TAM via intraperitoneal injection. But the introduction of TAM-infused commercial chows has recently expanded the possible modes of TAM delivery. Despite the widespread use of TAM-inducible genetic models in adult neurogenesis research, the comparative efficiency and off-target effects of TAM administration protocols is surprisingly infrequently studied. Here, we compare a standard, 5 d TAM injection regimen with voluntary consumption of TAM-infused chow. First, we used adult NestinCreERT2;Rosa-LoxP-STOP-LoxP-EYFP reporter mice to show that two weeks of TAM chow and 5 d of injections led to LoxP recombination in a similar phenotypic population of neural stem and progenitor cells (NSPCs) in the adult dentate gyrus. However, TAM chow resulted in substantially less overall recombination than injections. TAM administration also altered adult neurogenesis, but in different ways depending on administration route: TAM injection disrupted neural progenitor cell proliferation three weeks after TAM, whereas TAM chow increased neuronal differentiation of cells generated during the diet period. These findings provide guidance for selection of TAM administration route and appropriate controls in adult neurogenesis studies using TAM-inducible Cre mice. They also highlight the need for better understanding of off-target effects of TAM in other neurologic processes and organ systems.

Food and Nutrient Displacement by Walnut Supplementation in a Randomized Crossover Study.

The aim of this article is to evaluate the effect of a daily supplement of walnuts on the overall daily diet and nutrient profile of healthy adults. A randomized controlled trial with crossover design was conducted for two 6-month diet periods in southeast Californian communities. Subjects were randomized to receive a control diet or a walnut-supplemented diet, then switched. The walnut supplement represented approximately 12% of their daily energy intake. Trained nutritionists collected seven 24 h dietary recalls from each participant (a total of 14 recalls for both periods). Ninety participants were able to complete the study, including 50 females and 40 males. The average age of the participants was 54.3 years. Diets in the walnut period had significantly higher vegetable protein, total fat, total PUFA, PUFA 18:2, PUFA 22:6, and total dietary fiber (p < 0.05), while also exhibiting significantly lower PUFA 20:5. All mineral levels were higher on the walnut-supplemented diet. Calcium, phosphorus, magnesium, and zinc were, particularly, significantly higher among the walnut-supplemented group (p < 0.05). Displacement occurred in more than one-third of the entire nuts and seeds group; four-fifths of the non-alcoholic beverages and desserts groups; and the majority of the candy, sugar, and sweets group. Walnut supplementation can lead to favorable modifications in nutrient and food intake profiles that may contribute to chronic disease prevention. Nutrient and food displacement may be a mechanism to explain the favourable association between walnut intake and improved diet.

Plasma Metabolites Associated with a Protein-Rich Dietary Pattern: Results from the OmniHeart Trial.

ScopeLack of biomarkers is a challenge for the accurate assessment of protein intake and interpretation of observational study data. The study aims to identify biomarkers of a protein‐rich dietary pattern.Methods and ResultsThe Optimal Macronutrient Intake Trial to Prevent Heart Disease (OmniHeart) trial is a randomized cross‐over feeding study which tested three dietary patterns with varied macronutrient content (carbohydrate‐rich; protein‐rich with about half from plant sources; and unsaturated fat‐rich). In 156 adults, differences in log‐transformed plasma metabolite levels at the end of the protein‐ and carbohydrate‐rich diet periods using paired t‐tests is examined. Partial least‐squares discriminant analysis is used to identify a set of metabolites which are influential in discriminating between the protein‐rich versus carbohydrate‐rich dietary patterns. Of 839 known metabolites, 102 metabolites differ significantly between the protein‐rich and the carbohydrate‐rich dietary patterns after Bonferroni correction, the majority of which are lipids (n = 35), amino acids (n = 27), and xenobiotics (n = 24). Metabolites which are the most influential in discriminating between the protein‐rich and the carbohydrate‐rich dietary patterns represent plant protein intake, food or beverage intake, and preparation methods.ConclusionsThe study identifies many plasma metabolites associated with the protein‐rich dietary pattern. If replicated, these metabolites may be used to assess level of adherence to a similar dietary pattern.

The Impact of a High-Carbohydrate/Low Fat vs. Low-Carbohydrate Diet on Performance and Body Composition in Physically Active Adults: A Cross-Over Controlled Trial.

Background: Recently, high-carbohydrate or low-carbohydrate (HC/LC) diets have gained substantial popularity, speculated to improve physical performance in athletes; however, the effects of short-term changes of the aforementioned nutritional interventions remain largely unclear. Methods: The present study investigated the impact of a three-week period of HC/low-fat (HC) diet followed by a three-week wash-out-phase and subsequent LC diet on the parameters of physical capacity assessed via cardiopulmonary exercise testing, body composition via bioimpedance analysis and blood profiles, which were assessed after each of the respective diet periods. Twenty-four physically active adults (14 females, age 25.8 ± 3.7 years, body mass index 22.1 ± 2.2 kg/m2), of which six participants served as a control group, were enrolled in the study. Results: After three weeks of each diet, VO2peak was comparable following both interventions (46.8 ± 6.7 (HC) vs. 47.2 ± 6.7 mL/kg/min (LC; p = 0.58)) while a significantly higher peak performance (251 ± 43 W (HC) vs. 240 ± 45 W (LC); (p = 0.0001), longer time to exhaustion (14.5 ± 2.4 min (HC) vs. 14.1 ± 2.4 min (LC); p = 0.002) and greater Watt/kg performance (4.1 ± 0.5 W/kg (HC) vs. 3.9 ± 0.5 W/kg (LC); p = 0.003) was demonstrated after the HC diet. In both trial arms, a significant reduction in body mass (65.2 ± 11.2 to 63.8 ± 11.8 kg (HC) vs. 64.8 ± 11.6 to 63.5 ± 11.3 kg (LC); both p < 0.0001) and fat mass (22.7% to 21.2%; (HC) vs. 22.3% to 20.6% (LC); both p < 0.0001) but not in lean body mass or skeletal muscle mass was shown when compared to baseline. Resting metabolic rate was not different within both groups (p > 0.05). Total cholesterol and LDL-cholesterol significantly decreased after the HC diet (97.9 ± 33.6 mg/dL at baseline to 78.2 ± 23.5 mg/dL; p = 0.02) while triglycerides significantly increased (76 ± 38 mg/dL at baseline to 104 ± 44 mg/dL; p = 0.005). Conclusion: A short-term HC and LC diet showed improvements in various performance parameters in favor of the HC diet. Some parameters of body composition significantly changed during both diets. The HC diet led to a significant reduction in total and LDL-cholesterol while triglycerides significantly increased.

Daily intake of up to two eggs for 11weeks does not affect the cholesterol balance of Chinese young adults.

Approximately 90% of the cholesterol content of the body is derived from de novo synthesis and the enterohepatic circulation. As numerous studies have shown previously, one egg per day intake has little impact of cholesterol balance in human body. Therefore, this study assumed that intake of up two eggs a day has little effect on biomarkers of cardiovascular diseases (CVDs) risk in Chinese young adults. With the increase in egg intake, total cholesterol, low‐density lipoprotein cholesterol (LDL‐C), high‐density lipoprotein cholesterol (HDL‐C), and choline all increased among all the groups as the study progressed from autumn to winter (p < .05). However, there were no differences in the plasma triglycerides, LDL‐C/HDL‐C ratio, glucose, liver enzymes, C‐reactive protein, and urinary microalbumin during the diet periods. Subjects who ate eggs at breakfast felt less hungry and more satisfied, which were relative with decreased fasting plasma ghrelin level (p < .05). Furthermore, egg‐derived cholesterol appeared to upregulate the mRNA levels of low‐density lipoprotein receptor and lecithin–cholesterol acyltransferase, and downregulate cholesteryl ester transfer protein and flavin‐containing monooxygenase 3 mRNA levels in isolated peripheral blood mononuclear cells. These results demonstrate that intake of up to two eggs a day had little effect on biomarkers of CVDs in young, healthy Chinese college students and provided useful evidence for the dietary guidelines regarding egg consumption.

Residential Food Environment, Household Wealth and Maternal Education Association to Preschoolers' Consumption of Plant-Based Vitamin A-Rich Foods: The EAT Addis Survey in Addis Ababa.

Vitamin A deficiency is common among preschoolers in low-income settings and a serious public health concern due to its association to increased morbidity and mortality. The limited consumption of vitamin A-rich food is contributing to the problem. Many factors may influence children’s diet, including residential food environment, household wealth, and maternal education. However, very few studies in low-income settings have examined the relationship of these factors to children’s diet together. This study aimed to assess the importance of residential food availability of three plant-based groups of vitamin A-rich foods, household wealth, and maternal education for preschoolers’ consumption of plant-based vitamin A-rich foods in Addis Ababa. A multistage sampling procedure was used to enroll 5467 households with under-five children and 233 residential food environments with 2568 vendors. Data were analyzed using a multilevel binary logistic regression model. Overall, 36% (95% CI: 34.26, 36.95) of the study children reportedly consumed at least one plant-based vitamin A-rich food group in the 24-h dietary recall period. The odds of consuming any plant-based vitamin A-rich food were significantly higher among children whose mothers had a higher education level (AOR: 2.55; 95% CI: 2.01, 3.25), those living in the highest wealth quintile households (AOR: 2.37; 95% CI: 1.92, 2.93), and in residentials where vitamin A-rich fruits were available (AOR: 1.20; 95% CI: 1.02, 1.41). Further research in residential food environment is necessary to understand the purchasing habits, affordability, and desirability of plant-based vitamin A-rich foods to widen strategic options to improve its consumption among preschoolers in low-income and low-education communities.

Four weeks of spice consumption lowers plasma proinflammatory cytokines and alters the function of monocytes in adults at risk of cardiometabolic disease: secondary outcome analysis in a 3-period, randomized, crossover, controlled feeding trial

Numerous studies demonstrate acute anti-inflammatory properties of individual spices, but none have examined the effect of longer-term consumption of a spice blend incorporated in a meal. We investigated the effect of longer-term spice consumption on inflammatory cytokines and monocyte subsets [classical (CM), intermediate (IM), nonclassical (NCM)] in adults at risk of cardiometabolic disease. A 3-period, randomized, crossover, controlled feeding trial was conducted. Participants (n = 71 recruited; n = 63 completed) randomly consumed diets differing in terms of the quantity of spices: 0.547 g (low-dose spice diet; LSD), 3.285 g (medium-dose spice diet; MSD), or 6.571 g (high-dose spice diet; HSD) · d-1 · 2100 kcal-1, for 4 wk with a ≥2-wk washout between diets. At baseline and after each diet period, proinflammatory cytokines (IL-1β, IL-6, IL-8, monocyte chemoattractant protein-1, and TNF-α) in plasma and LPS-stimulated peripheral blood mononuclear cell culture supernatants, and the phenotype and function of monocyte subsets, were measured in fasted participants. Postprandial proinflammatory cytokines also were quantified at baseline by consumption of a low-spice-dose test meal, and after each diet period by consumption of a test meal containing a spice dose corresponding to daily spice consumption during the preceding 4-wk diet period. Fasting plasma IL-6 was reduced (mean ± SEM: -118.26 ± 50.63 fg/mL; P < 0.05) after MSD compared with baseline. Postprandial plasma IL-1β, IL-8, and TNF-α were lower (mean ± SEM : -9.47 ± 2.70 fg/mL, -0.20 ± 0.05 pg/mL, and -33.28 ± 12.35 fg/mL, respectively) after MSD compared with LSD (main diet effect; P < 0.05). CM adherence was reduced (mean ± SEM: -0.86 ± 0.34; P = 0.034) after HSD compared with LSD. IM migration was reduced after MSD and HSD compared with LSD (mean ± SEM: -0.39 ± 0.09 and -0.56 ± 0.14, respectively; P < 0.05). Four weeks of MSD consumption reduced fasting plasma IL-6 and postprandial plasma IL-1β, IL-8, and TNF-α as well as altering monocyte function.This trial was registered at clinicaltrials.gov as NCT03064932.

Metabolizable and Net Energy Values of Expanded Cottonseed Meal for Laying Hens and Broiler Chickens.

Three experiments were conducted to determine the metabolizable energy (ME) and net energy (NE) values of expanded cottonseed meal (ECSM) for broilers aged 14–16 days (Experiment 1), broilers aged 28–30 days (Experiment 2), and 45-week-old Hy-Line Brown hens (Experiment 3). Reference diets based on corn-soybean meal were used to meet the nutritional needs of the birds. The test diets contained ECSM as basis, which was used to replace 18.5% of the gross energy-yielding ingredients from the reference diet. The birds were fed a commercial feed before the experimental period. After the dietary adaptation period, six birds per replicate (Experiment 1) and two birds per replicate (Experiments 2 and 3) for each treatment group were placed in an individual open-circuit respiratory calorimetry chamber for 3 days. Daily O2 consumption and CO2 production were recorded, and excreta samples were collected. The ME and NE values of ECSM were determined using the substitution method. The apparent metabolizable energy (AME) values of ECSM for experiments 1, 2, and 3 were 2605.85, 2178.31, and 2782.60 kcal/kg of dry matter (DM), respectively. The NE values were 1655.23, 1196.64, and 1538.19 kcal/kg of DM, respectively. The NE:AME ratios of ECSM were 63.52%, 54.93%, and 55.29%, respectively. Our data showed that the ME and NE values of ECSM differed across various growth stages and types of chickens. These results demonstrate that the appropriate ME and NE should be used in the design of different feed formulas for specific growth stages and types of chickens.

Comparing Acute, High Dietary Protein and Carbohydrate Intake on Transcriptional Biomarkers, Fuel Utilisation and Exercise Performance in Trained Male Runners

Manipulating dietary macronutrient intake may modulate adaptive responses to exercise, and improve endurance performance. However, there is controversy as to the impact of short-term dietary modification on athletic performance. In a parallel-groups, repeated measures study, 16 trained endurance runners (maximal oxygen uptake (O2max): 64.2 ± 5.6 mL·kg−1·min−1) were randomly assigned to, and provided with, either a high-protein, reduced-carbohydrate (PRO) or a high-carbohydrate (CHO) isocaloric-matched diet. Participants maintained their training load over 21-consecutive days with dietary intake consisting of 7-days habitual intake (T1), 7-days intervention diet (T2) and 7-days return to habitual intake (T3). Following each 7-day dietary period (T1–T3), a micro-muscle biopsy was taken for assessment of gene expression, before participants underwent laboratory assessment of a 10 km treadmill run at 75% O2max, followed by a 95% O2max time to exhaustion (TTE) trial. The PRO diet resulted in a modest change (1.37-fold increase, p = 0.016) in AMPK expression, coupled with a significant increase in fat oxidation (0.29 ± 0.05 to 0.59 ± 0.05 g·min−1, p < 0.0001). However, a significant reduction of 23.3% (p = 0.0003) in TTE post intervention was observed; this reverted back to pre levels following a return to the habitual diet. In the CHO group, whilst no change in sub-maximal fuel utilisation occurred at T2, a significant 6.5% increase in TTE performance (p = 0.05), and a modest, but significant, increase in AMPK (p = 0.042) and PPAR (p = 0.029) mRNA expression compared to T1 were observed; with AMPK (p = 0.011) and PPAR (p = 0.044) remaining significantly elevated at T3. In conclusion, a 7-day isocaloric high protein diet significantly compromised high intensity exercise performance in trained runners with no real benefit on gene markers of training adaptation. A significant increase in fat oxidation during submaximal exercise was observed post PRO intervention, but this returned to pre levels once the habitual diet was re-introduced, suggesting that the response was driven via fuel availability rather than cellular adaptation. A short-term high protein, low carbohydrate diet in combination with endurance training is not preferential for endurance running performance.

Proposed Anti-Inflammatory Diet Reduces Inflammation in Compliant, Weight-Stable Patients with Rheumatoid Arthritis in a Randomized Controlled Crossover Trial

BackgroundIt is unclear to what extent adjuvant dietary intervention can influence inflammation in rheumatoid arthritis (RA). ObjectivesThe objective was to assess the effects of dietary manipulation on inflammation in patients with RA. MethodsIn a crossover design, participants [n = 50, 78% females, median BMI (in kg/m2) 27, median age 63 y] were randomly assigned to begin with either a 10-wk portfolio diet of proposed anti-inflammatory foods (i.e., a high intake of fatty fish, whole grains, fruits, nuts, and berries) or a control diet resembling a Western diet with a 4-mo washout in between. This report evaluates the secondary outcome markers of inflammation among participants with stable medication. Analyses were performed using a linear mixed ANCOVA model. ResultsThere were no significant effects on CRP or ESR in the group as a whole. In those with high compliance (n = 29), changes in ESR within the intervention diet period differed significantly compared with changes within the control diet period (mean: –5.490; 95% CI: –10.310, –0.669; P = 0.027). During the intervention diet period, there were lowered serum concentrations of C-X-C motif ligand 1 (CXCL1) (mean: –0.268; 95% CI: –0.452, –0.084;P = 0.006), CXCL5 (mean: –0.278; 95% CI: –0.530, –0.026 P = 0.031), CXCL6 (mean: –0.251; 95% CI: –0.433, –0.069; P = 0.009), and tumor necrosis factor ligand superfamily member 14 (TNFSF14) (mean: –0.139; 95% CI: –0.275, –0.002; P = 0.047) compared with changes within the control diet period. ConclusionA proposed anti-inflammatory diet likely reduced systemic inflammation, as indicated by a decreased ESR in those who completed the study with high compliance (n = 29). These findings warrant further studies to validate our results, and to evaluate the clinical relevance of changes in CXCL1, CXCL5, CXCL6, and TNFSF14 in patients with RA.

Blocking myeloid differentiation factor 2 improves cognitive function via reducing microglia activation, neuroinflammation, brain mitochondrial dysfunction and dendritic spine loss in obese insulin‐resistant rats

Chronic high fat diet (HFD) consumption induces not only low-grade systemic inflammation and obese-insulin resistance, but also initiates neuroinflammation via activating myeloid differentiation factor 2 (MD-2)/toll-like receptor 4 (TLR4) complex, resulting in brain pathologies and cognitive impairment. Recently, MD-2 inhibitor (L6H21) has been shown to alleviate systemic inflammation. However, the effect of L6H21 on the cognitive function and brain pathologies of HFD-induced obese insulin-resistant condition has not been investigated. Male Wistar rats were fed either a normal diet (ND; n=8) or HFD (n=40) for 16 weeks. After 12th week of dietary periods, HFD-fed rats were divided into 5 groups (n=8/group). Each group was orally administered either vehicle, 10 mg/kg/day of L6H21, 20 mg/kg/day of L6H21, 40 mg/kg/day of L6H21, or 300 mg/kg/day of metformin for 4 weeks. For ND-fed rats, animals were orally administered vehicle for 4 weeks. At the end of experimental protocol, the novel object location (NOL) test was examined in each animal. Then, blood was collected before animals were sacrificed. Brains were rapidly removed to determine microglial activity, dendritic spine density, inflammatory cytokines, mitochondrial function, and insulin signaling. HFD-fed rats showed peripheral and brain insulin resistance, as indicated by impaired glucose tolerance and reduced brain insulin receptor substrate (IRS) level. In addition, HFD-fed rats developed brain pathologies, and cognitive impairment, as indicated by increased brain TNF-α level, increased microglial hyperactivity, increased mitochondrial reactive oxygen species (ROS), increased Bax/Bcl2 level, reduced dendritic spine density, and reduced preference indexes of NOL phase. Although L6H21 (20mg/kg/day, 40 mg/kg/day) and metformin alleviated HFD-induced brain pathologies and cognitive impairment, L6H21 at 40mg/kg/day and metformin had the highest efficacy for the neuroprotection in obese insulin-resistant rats through inhibiting neuroinflammation, oxidative stress, microglial activation, neuronal apoptosis and improving dendritic spine density, resulting in restoring cognitive function (p<0.05, Figure 1). These findings suggest that MD-2 inhibitor may be the other drug of choice for improving brain function in the obese-insulin resistant condition.

Diurnal glycemic pattern on inclusion of sucrose in daily meals in type 2 diabetes: Reflection of antecedent glycemic control

Background: Inclusion of sucrose in diabetic diets is not recommended in subjects with diabetes since effects of such diets on glycemic indices are not established. Some studies have documented lapse in metabolic control on consumption of these diets type 2 diabetes. However, most studies examined plasma glucose only for a few hours after ingestion of a single meal containing sucrose after an overnight fast whereas others recommended increasing insulin dose prior to the meal. None of these studies examined influence of inclusion of sucrose in daily meals in subjects with new onset diabetes at diagnosis and again after achieving desirable glycemic control. Objective : Study was conducted to assess glycemic responses to ingestion of all meals containing sucrose constituting 50% of carbohydrate calories. Methods: 12 subjects with new onset type 2 diabetes participated. They were administered the following isocaloric diets for 4 days each prior to and after achieving desirable glycemic control; Diet 1- Diabetic diet recommended by American Diabetes Association (ADA), diet 2- test diet containing sucrose, diet 3- ADA diet. Glycemic control was assessed by diurnal glycemia (average of pre-prandial, postprandial and bedtime blood glucose), fasting plasma glucose, HbA1c and fructosamine on 4th day of each dietary period. Results: All glycemic indices deteriorated after consumption of sucrose containing meals prior to initiation of treatment and remained worsened on return to ingestion of ADA diet. Glycemic responses after all meals improved markedly on achieving desirable glycemic control. Moreover, glycemic indices remained unaltered on consumption of sucrose containing meals after attaining and maintaining desirable glycemic control. Conclusion: Diurnal glycemic responses deteriorate on ingestion of daily meals containing sucrose in subjects with new onset uncontrolled type 2 diabetes. In contrast, diurnal glycemic pattern is unaltered following consumption of daily meals containing sucrose after attaining and maintaining desirable glycemic control.

Dietary Observations of Ultra-Endurance Runners in Preparation for and During a Continuous 24-h Event.

Carbohydrate (CHO) intake recommendations for events lasting longer than 3h indicate that athletes should ingest up to 90g.h.−1 of multiple transportable carbohydrates (MTC). We examined the dietary intake of amateur (males: n=11, females: n=7) ultra-endurance runners (mean age and mass 41.5±5.1years and 75.8±11.7kg) prior to, and during a 24-h ultra-endurance event. Heart rate and interstitial glucose concentration (indwelling sensor) were also tracked throughout the event. Pre-race diet (each 24 over 48h) was recorded via weighed intake and included the pre-race meal (1–4h pre-race). In-race diet (24h event) was recorded continuously, in-field, by the research team. Analysis revealed that runners did not meet the majority of CHO intake recommendations. CHO intake over 24–48h pre-race was lower than recommended (4.0±1.4g·kg−1; 42±9% of total energy), although pre-race meal CHO intake was within recommended levels (1.5±0.7g·kg−1). In-race CHO intake was only in the 30–60g·h−1 range (mean intake 33±12g·h−1) with suboptimal amounts of multiple transportable CHO consumed. Exercise intensity was low to moderate (mean 68%HRmax 45%VO2max) meaning that there would still be an absolute requirement for CHO to perform optimally in this ultra-event. Indeed, strong to moderate positive correlations were observed between distance covered and both CHO and energy intake in each of the three diet periods studied. Independent t-tests showed significantly different distances achieved by runners consuming ≥5 vs. <5g·kg−1 CHO in pre-race diet [98.5±18.7miles (158.5±30.1km) vs. 78.0±13.5miles (125.5±21.7km), p=0.04] and ≥40 vs. <40g·h−1 CHO in-race [92.2±13.9miles (148.4±22.4km) vs. 74.7±13.5miles (120.2±21.7km), p=0.02]. Pre-race CHO intake was positively associated with ultra-running experience, but no association was found between ultra-running experience and race distance. No association was observed between mean interstitial glucose and dietary intake, or with race distance. Further research should explore approaches to meeting pre-race dietary CHO intake as well as investigating strategies to boost in-race intake of multiple transportable CHO sources. In 24-h ultra-runners, studies examining the performance enhancing benefits of getting closer to meeting pre-race and in-race carbohydrate recommendations are required.

Short high fat diet triggers reversible and region specific effects in DCX+ hippocampal immature neurons of adolescent male mice

Adolescence represents a crucial period for maturation of brain structures involved in cognition. Early in life unhealthy dietary patterns are associated with inferior cognitive outcomes at later ages; conversely, healthy diet is associated with better cognitive results. In this study we analyzed the effects of a short period of hypercaloric diet on newborn hippocampal doublecortin+ (DCX) immature neurons in adolescent mice. Male mice received high fat diet (HFD) or control low fat diet (LFD) from the 5th week of age for 1 or 2 weeks, or 1 week HFD followed by 1 week LFD. After diet supply, mice were either perfused for immunohistochemical (IHC) analysis or their hippocampi were dissected for biochemical assays. Detailed morphometric analysis was performed in DCX+ cells that displayed features of immature neurons. We report that 1 week-HFD was sufficient to dramatically reduce dendritic tree complexity of DCX+ cells. This effect occurred specifically in dorsal and not ventral hippocampus and correlated with reduced BDNF expression levels in dorsal hippocampus. Both structural and biochemical changes were reversed by a return to LFD. Altogether these studies increase our current knowledge on potential consequences of hypercaloric diet on brain and in particular on dorsal hippocampal neuroplasticity.

Effects of intervention of sodium alginate on intakes of foods and macronutrients and situation of serum amino acids in healthy male youths

To research the effect of sodium alginate intervention on the nutritional intake of healthy young men. Recruited 20 healthy university students as research subjects. The experiment was divided into two periods: the dietary balance period and the sodium alginate intervening period, and each period was expected to be 28 days. During the dietary balance period, all meals in every day of experiment are provided by the research team; during the sodium alginate intervening period, based on the diet during the balanced diet period, sodium alginate was added to the staple food steamed buns(10 g sodium alginate per person per day). The experiment compares the food intake types, main nutrient intake levels and serum amino acid changes of subjects before and after intervention. Adding sodium alginate can significantly reduce the intake of energy(-242.4 kcal), protein(-11 g)and carbohydrates(-47.3 g, P&lt;0.05)in healthy subjects, but there was no significant effect on the intake of fat(-2.9 g, P=0.496)and cholesterol(-14.9 mg, P=0.070), and because of the addition of alginate, the whole dietary fibers obtained a significant increase(+7.8 g, P&lt;0.05). After the intervention of sodium alginate, there was no significant change in the intake of rice, soy products, poultry products and vegetable oil, while the intake of wheat products(-49.6 g), egg foods(-2.6 g), dark-colored vegetables(-29.1 g), light-colored vegetables(-63.8 g)and fruits(-37 g)decreased significantly(P&lt;0.05). Most of the essential amino acids in the subjects&apos; serum increased significantly after the intervention, especially the valine in serum rise from 226.9 μmol/L to 466.4 μmol/L(P&lt;0.05). Sodium alginate can play a dietary fiber-like effect, produce satiety, reduce nutrient intake of subjects, especially carbohydrates, so sodium alginate has the potential to limit energy intake and control postprandial blood sugar. And sodium alginate also has a potential positive effect on the metabolism of amino acids in healthy people, especially the metabolism of essential amino acids.

Effects of an array of dietary treatments and length of feeding on ruminal methane emission and other variables in hair sheep

Eighteen Katahdin sheep ewes (initial body weight [BW] = 73.7 ± 1.76 kg and age = 5.2 ± 0.56 yr) and 18 St. Croix ewes (54.7 ± 1.33 kg BW and 4.1 ± 0.42 yr) were used in an experiment to determine effects of dietary level of Sericea lespedeza (Lespedeza cuneata; 5.8% condensed tannins and 10.3 % crude protein, dry matter [DM] basis) and other supplemental ingredients on BW, feed intake, digestion, energy metabolism, ruminal methane emission, and levels of blood and ruminal fluid constituents. Diets were consumed ad libitum and included a concentrate supplement at approximately 0.45 % BW (DM). Alfalfa (Medicago sativa) was the basal forage for control (CON), ionophore (ION; lasalocid at 33 mg/kg DM), coconut oil (3%; CCO), and soybean oil (3%; SBO) diets, and forage in moderate- and high-lespedeza diets was a 1:1 mixture of alfalfa and lespedeza and all lespedeza, respectively (ALF:LES and LES, respectively). There were four 6-wk periods, with digestion assessed in wk 4 and measures with a respiration calorimetry system in wk 5. Although there was a three-way interaction involving dietary treatment, breed, and period, average forage intake was greater for LES than for CON, ION, CCO, SBO (P < 0.05), and ALF:LES (P = 0.062; 988, 1072, 1265, 987, 951, and 1057 g/day for CON, ALF:LES, LES, ION, CCO, and SBO, respectively; standard error of the mean [SEM] = 69.4). Dietary level of lespedeza had marked effects (P < 0.05) on digestion of organic matter [OM] (69.2, 57.6, 50.3, 66.3, 66.0, and 68.7 %; SEM = 1.57) and nitrogen (78.3, 65.3, 46.8, 71.4, 73.9, and 75.7 %; SEM = 1.81), with digestible OM intake numerically lower (P > 0.05) for diets with lespedeza and for ION (697, 607, 589, 598, 635, and 690 g/day for CON, ALF:LES, LES, ION, CCO, and SBO, respectively; SEM = 50.4). There was a treatment by period interaction (P < 0.05) in ruminal methane emission relative to digestible energy intake, but overall, emission was greatest among treatments (P < 0.05) for CON (12.33, 9.92, 10.24, 10.41, 8.91, and 8.66 % for CON, ALF:LES, LES, ION, CCO, and SBO, respectively; SEM = 0.730). Average daily gain (ADG) was greatest among treatments (P < 0.05) for SBO (54, 28, 18, 40, 56, and 98 g; SEM = 13.2). Many findings are not closely aligned with those of previous studies with goats. For example, effects of lespedeza on feed intake and ruminal methane emission were greater in the first than second half of the experiment, though interactions observed could not be clearly attributed to factors such as microbial adaptation. The effect of the SBO diet on ADG with the alfalfa-based diet deserves future research attention.

Lower Interstitial Glucose Concentrations but Higher Glucose Variability during Low-Energy Diet Compared to Regular Diet-An Observational Study in Females with Obesity.

This is an observational study of interstitial glucose (IG) concentrations, IG variability and dietary intake under free-living conditions in 46 females with obesity but without diabetes. We used continuous glucose monitoring, open-ended food recording and step monitoring during regular dietary intake followed by a low-energy diet (LED). Thirty-nine participants completed both study periods. The mean BMI at baseline was 43.6 ± 6.2 kg/m2. Three weeks of LED resulted in a mean weight loss of 5.2% with a significant reduction in diurnal IG concentration but with greater glycemic variability observed during LED. The mean 24 h IG concentration decreased from 5.8 ± 0.5 mmol/L during the regular diet period to 5.4 ± 0.5 mmol/L (p < 0.001) during LED, while the mean amplitude of glycemic excursion increased from 1.5 ± 0.7 to 1.7 ± 0.7 mmol/L (p = 0.031). The positive incremental area under the curve at breakfast was significantly larger for LED compared to regular diet. The daily fiber intake and the glycemic index of breakfast meals were significantly associated with the glycemic variability during regular dietary intake. In conclusion, the 24 h mean IG concentration was lower but with more pronounced glycemic variability during LED compared to a regular diet.

Dpp4+ interstitial progenitor cells contribute to basal and high fat diet-induced adipogenesis

ObjectiveThe capacity to generate new adipocytes from precursor cells is critical for maintaining metabolic health. Adipocyte precursor cells (APCs) constitute a heterogenous collection of cell types; however, the contribution of these various cell types to adipose tissue expansion in vivo remains unknown. The aim of the current study is to investigate the contribution of Dpp4+ progenitors to de novo adipogenesis. MethodsSingle cell analysis has identified several transcriptionally distinct subpopulations of APCs, including Dpp4+ progenitor cells concentrated in the connective tissue surrounding many organs, including white adipose tissue (WAT). Here, we generated a Dpp4CreER mouse model for in vivo lineage tracing of these cells and their downstream progeny in the setting of basal or high fat diet (HFD)-stimulated adipogenesis. ResultsDpp4CreER mice enabled specific temporal labeling of Dpp4+ progenitor cells within their native connective tissue niche. Following a dietary chase period consisting of chow or HFD feeding for 18 weeks, Dpp4+ progenitors differentiated into mature adipocytes within the gonadal and subcutaneous WAT. HFD stimulated adipogenic contribution from Dpp4+ cells in the gonadal but not the subcutaneous depot. Flow cytometry analysis revealed that Dpp4+ progenitors give rise to DPP4(−)/ICAM1+ preadipocytes in vivo. HFD feeding did not perturb the flux of Dpp4+ cell conversion into ICAM1+ preadipocytes in gonadal WAT. Conversely, in subcutaneous WAT, HFD feeding/obesity led to an accumulation of ICAM1+ preadipocytes without a corresponding increase in mature adipocyte differentiation. Examination of non-classical murine visceral depots with relevance to humans, including omentum and retroperitoneal WAT, revealed robust contribution of Dpp4+ progenitors to de novo adipogenesis, which was further stimulated by HFD. ConclusionOur data demonstrate that Dpp4+ interstitial progenitor cells contribute to basal adipogenesis in all fat depots and are recruited to support de novo adipogenic expansion of visceral WAT in the setting of HFD-induced obesity.

Effects on health-related quality of life in the randomized, controlled crossover trial ADIRA (Anti-inflammatory Diet In Rheumatoid Arthritis).

Patients with Rheumatoid Arthritis (RA) often report impaired health-related quality of life (HrQoL) such as difficulties in daily life, pain, fatigue and an affected social life. Even when lowering disease activity, pharmacological treatment does not always resolve these factors. To investigate if a proposed anti-inflammatory diet improves HrQoL in patients with RA. In this controlled crossover trial, 50 patients were randomized to start with either an intervention diet (anti-inflammatory) or a control diet (usual Swedish intake) for ten weeks followed by a wash out period before switching to the other diet. Participants received food equivalent to ~1100 kcal/day, five days/week, and instructions to consume similarly for the remaining meals. HrQoL was evaluated using Health Assessment Questionnaire (HAQ), 36-item Short Form Survey (SF-36), Visual Analogue Scales (VAS) for pain, fatigue and morning stiffness, and a time scale for morning stiffness. Forty-seven participants completed ≥1 diet period and were included in the main analyses. No significant difference between intervention and control diet at end of diet periods was observed for any outcome. However, significant improvements were obtained for SF-36 Physical Functioning (mean:5.79, SE: 2.12, 95% CI: 1.58, 10.01) during the intervention diet period. When excluding participants with anti-rheumatic medication changes, the differences between diet periods increased for most outcomes, favoring the intervention diet period, and the difference for SF-36 Physical Functioning became significant (n = 25, mean:7.90, 95% CI:0.56, 15.24, p = 0.036). In main analyses, the proposed anti-inflammatory diet did not significantly improve HrQoL for patients with RA compared to control diet. In sub-analyses, significant improvements in physical functioning were detected. Larger studies with consistent medication use and in populations more affected by the disease may be needed to obtain conclusive evidence.