Effects of Human Milk Oligosaccharide 2'-Fucosyllactose Ingestion on Weight Loss and Markers of Health.

BACKGROUND: 2'-Fucosyllactose (2'-FL) is an oligosaccharide contained in human milk and possesses prebiotic and anti-inflammatory effects, which may alleviate skeletal muscle atrophy under caloric restriction. This study evaluated the impacts of 12 weeks of 2'-FL supplementation in conjunction with exercise (10,000 steps/day, 5 days/week) and energy-reduced (-300 kcals/day) dietary interventions on changes in body composition and health-related biomarkers. METHODS: A total of 41 overweight and sedentary female and male participants (38.0 ± 13 years, 90.1 ± 15 kg, 31.6 ± 6.6 kg/m2, 36.9 ± 7% fat) took part in a randomized, double-blind, and placebo-controlled study. The participants underwent baseline assessments and were then assigned to ingest 3 g/day of a placebo (PLA) or Momstamin 2'-F while initiating the exercise and weight-loss program. Follow-up tests were performed after 6 and 12 weeks. Data were analyzed using general linear model statistics with repeated measures and mean changes from baseline values with 95% confidence intervals (CIs). RESULTS: No group × time × sex interaction effects were observed, so group × time effects are reported. Participants in both groups saw comparable reductions in weight. However, those with 2'-FL demonstrated a significantly greater reduction in the percentage of body fat and less loss of the fat-free mass. Additionally, there was evidence that 2'-FL supplementation promoted more favorable changes in resting fat oxidation, peak aerobic capacity, IL-4, and platelet aggregation, with some minimal effects on the fermentation of short-chain fatty acids and monosaccharides in fecal samples. Moreover, participants' perceptions regarding some aspects of the functional capacity and ratings of the quality of life were improved, and the supplementation protocol was well tolerated, although a small, but significant, decrease in BMC was observed. CONCLUSIONS: The results support contentions that dietary supplementation of 2'-FL (3 g/d) can promote fat loss and improve exercise- and diet-related markers of health and fitness in overweight sedentary individuals initiating an exercise and weight-loss program. Further research is needed to explore the potential health benefits of 2'-FL supplementation in both healthy and elderly individuals (Registered clinical trial #NCT06547801).

The influence of time-restricted eating/feeding on Alzheimer's biomarkers and gut microbiota.

OBJECTIVES: Alzheimer's disease (AD) is a progressive neurodegenerative disorder affecting approximately 55 million individuals globally. Diagnosis typically occurs in advanced stages, and there are limited options for reversing symptoms. Preventive strategies are, therefore, crucial. Time Restricted Eating (TRE) or Time Restricted Feeding (TRF) is one such strategy. Here we review recent research on AD and TRE/TRF in addition to AD biomarkers and gut microbiota. METHODS: A comprehensive review of recent studies was conducted to assess the impact of TRE/TRF on AD-related outcomes. This includes the analysis of how TRE/TRF influences circadian rhythms, beta-amyloid 42 (Aß42), pro-inflammatory cytokines levels, and gut microbiota composition. RESULTS: TRE/TRF impacts circadian rhythms and can influence cognitive performance as observed in AD. It lowers beta-amyloid 42 deposition in the brain, a key AD biomarker, and reduces pro-ininflammatory cytokines. The gut microbiome has emerged as a modifiable factor in AD treatment. TRE/TRF changes the structure and composition of the gut microbiota, leading to increased diversity and a decrease in harmful bacteria. DISCUSSION: These findings underscore the potential of TRE/TRF as a preventive strategy for AD. By reducing Aß42 plaques, modulating pro-inflammatory cytokines, and altering gut microbiota composition, TRE/TRF may slow the progression of AD. Further research is needed to confirm these effects and to understand the mechanisms involved. This review highlights TRE/TRF as a promising non-pharmacological intervention in the fight against AD.

The Effect of Short-Term NAD3® Supplementation on Circulating Adult Stem Cells in Healthy Individuals Aged 40-70 Years.

Objective This study aimed to assess the impact of acute and short-term supplementation with NAD3®, a theacrine-containing supplement, on circulating adult stem cell numbers in a healthy male and female population aged 40-70 years. Methods This was a double-blind, placebo-controlled crossover study with 12 participants randomized to receive either NAD3® or a placebo for seven days. Blood samples were collected after an overnight fast, before and after the seven-day supplementation period, and one and two hours after the final supplement dose. Using flow cytometry, circulating stem cells, including lymphocytoid CD34+ stem cells (CD45dimCD34+), stem cells associated with vascular maintenance and repair (CD45dimCD34+CD309+), CD34+ stem cells linked to a progenitor phenotype (CD45dimCD34+CD309neg), circulating endothelial stem cells (CD45negCD31+CD309+), and mesenchymal stem cells (CD45negCD90+) were quantified. Results Acute NAD3® supplementation did not result in the mobilization of stem cells from the bone marrow. However, seven days of daily NAD3® supplementation resulted in selective changes in circulating stem cell numbers. A significant time*treatment interaction was observed for CD45dimCD34+ cells (p=0.04) and CD45dimCD34+CD309neg cells (p=0.04), indicating a decrease in cell numbers with supplementation. There was also a trend toward an increase in circulating endothelial cells (p=0.08) with seven days of NAD3®supplementation. Conclusion Short-term NAD3® supplementation demonstrated an effect on the quantity of bone marrow-derived stem cells in circulation. The study suggests that this theacrine-containing supplement may play a role in modulating adult stem cell populations, emphasizing the potential impact of NAD3® on regenerative processes. Further research with extended supplementation periods and larger sample sizes is warranted to elucidate the functional consequences of these changes and explore the therapeutic implications for age-related declines in stem cell function.

Safety and efficacy of a probiotic cocktail containing P. acidilactici and L. plantarum for gastrointestinal discomfort in endurance runners: randomized double-blinded crossover clinical trial.

Probiotics are increasingly used to treat conditions associated with gastrointestinal injury and permeability, including exercise-induced gastrointestinal discomfort. This study assessed safety and efficacy of a probiotic in altering the intestinal milieu and mitigating gastrointestinal symptoms (GIS) in endurance runners. In a double blind, crossover study, 16 runners were randomized to 4 weeks of daily supplementation with a probiotic cocktail containing Pediococcus acidilactici bacteria and Lactobacillus plantarum or placebo. Fasting blood and stool samples were collected for measurement of gut permeability markers, immune parameters, and microbiome analyses. Treadmill run tests were performed before and after treatment; participants ran at 65%-70% of VO2max at 27 °C for a maximum of 90 min or until fatigue/GIS developed. A blood sample was collected after the treadmill run test. In healthy individuals, 4 weeks of probiotic supplementation did not alter health parameters, although a marginal reduction in aspartate aminotransferase levels was observed with probiotic treatment only (p = 0.05). GIS, gut permeability-associated parameters (intestinal fatty acid binding protein, lipopolysaccharide binding protein, zonulin, and cytokines), and intestinal microbial content were not altered by the probiotic supplementation. Post-run measurements of GIS and gut-associated parameters did not differ between groups; however, the observed lack of differences is confounded by an absence of measurable functional outcome as GIS was not sufficiently induced during the run. Under the current study conditions, the probiotic was safe to use, and did not affect gut- or immune-associated parameters, or intestinal symptoms in a healthy population. The probiotic might reduce tissue damage, but more studies are warranted.

Rapid and automated lipid profiling by nuclear magnetic resonance spectroscopy using neural networks.

Nuclear magnetic resonance (NMR) spectroscopy is a powerful tool for quantitative metabolomics; however, quantification of metabolites from NMR data is often a slow and tedious process requiring user input and expertise. In this study, we propose a neural network approach for rapid, automated lipid identification and quantification from NMR data. Multilayered perceptron (MLP) networks were developed with NMR spectra as the input and lipid concentrations as output. Three large synthetic datasets were generated, each with 55,000 spectra from an original 30 scans of reference standards, by using linear combinations of standards and simulating experimental-like modifications (line broadening, noise, peak shifts, baseline shifts) and common interference signals (water, tetramethylsilane, extraction solvent), and were used to train MLPs for robust prediction of lipid concentrations. The performances of MLPS were first validated on various synthetic datasets to assess the effect of incorporating different modifications on their accuracy. The MLPs were then evaluated on experimentally acquired data from complex lipid mixtures. The MLP-derived lipid concentrations showed high correlations and slopes close to unity for most of the quantified lipid metabolites in experimental mixtures compared with ground-truth concentrations. The most accurate, robust MLP was used to profile lipids in lipophilic hepatic extracts from a rat metabolomics study. The MLP lipid results analyzed by two-way ANOVA for dietary and sex differences were similar to those obtained with a conventional NMR quantification method. In conclusion, this study demonstrates the potential and feasibility of a neural network approach for improving speed and automation in NMR lipid profiling and this approach can be easily tailored to other quantitative, targeted spectroscopic analyses in academia or industry.

Effect of Omega-3 Rich High-Fat Diet on Markers of Tissue Lipid Metabolism in Glucocorticoid-Treated Mice.

Glucocorticoids (GCs) are some of the most widely prescribed therapies for treating numerous inflammatory diseases and multiple cancer types. With chronic use, GCs' therapeutic benefits are concurrent with deleterious metabolic side effects, which worsen when combined with a high-fat diet (HFD). One characteristic of the common Western HFD is the presence of high omega-6 polyunsaturated fatty acids (PUFAs) and a deficiency in omega-3 PUFAs. The aim of this experiment was to determine whether fat composition resulting from HFD affects glucocorticoid-induced alterations in lipid-handling by the liver and skeletal muscle. Male wild-type C57BL/6 mice were randomized into two groups: n-6 (45% fat 177.5 g lard) and n-3 (45% fat 177.5 g Menhaden oil). After 4 weeks on their diets, groups were divided to receive either daily injections of dexamethasone (3 mg/kg/day) or sterile PBS for 1 week while continuing diets. The n-3 HFD diet attenuated adipose and hepatic fatty accumulation and prevented GC-induced increases in liver lipid metabolism markers Cd36 and Fabp. N-3 HFD had little effect on markers of lipid metabolism in oxidative and glycolytic skeletal muscle and was unable to attenuate GC-induced gene expression in the muscle. The present study's result demonstrated that the change of fat composition in HFD could beneficially alter the fatty acid accumulation and associated lipid metabolism markers in mice treated with dexamethasone.

Fasting Protocols Do Not Improve Intestinal Architecture and Immune Parameters in C57BL/6 Male Mice Fed a High Fat Diet.

BACKGROUND: The intestinal ecosystem, including epithelium, immune cells, and microbiota, are influenced by diet and timing of food consumption. The purpose of this study was to evaluate various dietary protocols after ad libitum high fat diet (HFD) consumption on intestinal morphology and mucosal immunity. METHODS: C57BL/6 male mice were fed a 45% high fat diet (HFD) for 6 weeks and then randomized to the following protocols; (1) chow, (2) a purified high fiber diet known as the Daniel Fast (DF), HFD consumed (3) ad libitum or in a restricted manner; (4) caloric-restricted, (5) time-restricted (six hours of fasting in each 24 h), or (6) alternate-day fasting (24 h fasting every other day). Intestinal morphology and gut-associated immune parameters were investigated after 2 months on respective protocols. RESULTS: Consuming a HFD resulted in shortening of the intestine and reduction in villi and crypt size. Fasting, while consuming the HFD, did not restore these parameters to the extent seen with the chow and DF diet. Goblet cell number and regulatory T cells had improved recovery with high fiber diets, not seen with the HFD irrespective of fasting. CONCLUSION: Nutritional content is a critical determinant of intestinal parameters associated with gut health.

Multi-Tissue Time-Domain NMR Metabolomics Investigation of Time-Restricted Feeding in Male and Female Nile Grass Rats.

Metabolic disease resulting from overnutrition is prevalent and rapidly increasing in incidence in modern society. Time restricted feeding (TRF) dietary regimens have recently shown promise in attenuating some of the negative metabolic effects associated with chronic nutrient stress. The purpose of this study is to utilize a multi-tissue metabolomics approach using nuclear magnetic resonance (NMR) spectroscopy to investigate TRF and sex-specific effects of high-fat diet in a diurnal Nile grass rat model. Animals followed a six-week dietary protocol on one of four diets: chow ad libitum, high-fat ad libitum (HF-AD), high-fat early TRF (HF-AM), or high-fat late TRF (HF-PM), and their liver, heart, and white adipose tissues were harvested at the end of the study and were analyzed by NMR. Time-domain complete reduction to amplitude-frequency table (CRAFT) was used to semi-automate and systematically quantify metabolites in liver, heart, and adipose tissues while minimizing operator bias. Metabolite profiling and statistical analysis revealed lipid remodeling in all three tissues and ectopic accumulation of cardiac and hepatic lipids for HF-AD feeding compared to a standard chow diet. Animals on TRF high-fat diet had lower lipid levels in the heart and liver compared to the ad libitum group; however, no significant differences were noted for adipose tissue. Regardless of diet, females exhibited greater amounts of hepatic lipids compared to males, while no consistent differences were shown in adipose and heart. In conclusion, this study demonstrates the feasibility of performing systematic and time-efficient multi-tissue NMR metabolomics to elucidate metabolites involved in the crosstalk between different metabolic tissues and provides a more holistic approach to better understand the etiology of metabolic disease and the effects of TRF on metabolic profiles.

Early Time-Restricted Feeding Amends Circadian Clock Function and Improves Metabolic Health in Male and Female Nile Grass Rats.

Lengthening the daily eating period contributes to the onset of obesity and metabolic syndrome. Dietary approaches, including energy restriction and time-restricted feeding, are promising methods to combat metabolic disorders. This study explored the effect of early and late time-restricted feeding (TRF) on weight and adiposity, food consumption, glycemic control, clock gene expression, and liver metabolite composition in diurnal Nile grass rats (NGRs). Adult male and female Nile grass rats were randomly assigned to one of three groups: (1) access to a 60% high-fat (HF) diet ad-libitum (HF-AD), (2) time-restricted access to the HF diet for the first 6 h of the 12 h light/active phase (HF-AM) or (3) the second 6 h of the 12 h light/active phase (HF-PM). Animals remained on their respective protocols for six weeks. TRF reduced total energy consumption and weight gain, and early TRF (HF-AM) reduced fasting blood glucose, restored Per1 expression, and reduced liver lipid levels. Although sex-dependent differences were observed for fat storage and lipid composition, TRF improved metabolic parameters in both male and female NGRs. In conclusion, this study demonstrated that early TRF protocol benefits weight management, improves lipid and glycemic control, and restores clock gene expression in NGRs.

Effects of Feeding Time on Markers of Muscle Metabolic Flexibility Following Acute Aerobic Exercise in Trained Mice Undergoing Time Restricted Feeding.

Time-restricted feeding (TRF) is becoming a popular way of eating in physically active populations, despite a lack of research on metabolic and performance outcomes as they relate to the timing of food consumption in relation to the time of exercise. The purpose of this study was to determine if the timing of feeding/fasting after exercise training differently affects muscle metabolic flexibility and response to an acute bout of exercise. Male C57BL/6 mice were randomized to one of three groups for 8 weeks. The control had ad libitum access to food before and after exercise training. TRF-immediate had immediate access to food for 6 h following exercise training and the TRF-delayed group had access to food 5-h post exercise for 6 h. The timing of fasting did not impact performance in a run to fatigue despite TRF groups having lower hindlimb muscle mass. TRF-delayed had lower levels of muscle HSL mRNA expression and lower levels of PGC-1α expression but displayed no changes in electron transport chain enzymes. These results suggest that in young populations consuming a healthy diet and exercising, the timing of fasting may not substantially impact metabolic flexibility and running performance.

Gut microbiome changes induced by a diet rich in fruits and vegetables.

Habitual dietary intake is a major determinant of the species composition and functional output of the trillions of microorganisms residing in the human gut. Diet influences which microbes will colonise, flourish or disappear throughout life. An increase in polyphenols, oligosaccharides and fibre, which are all components found in a fruit and vegetable-rich diet, have long been associated with decreased risk of chronic diseases. Many of the benefits induced by this type of diet result from the interaction of these dietary components with the gut microbiome, where they selectively enrich specific microbial species and increase microbial diversity. Understanding the interaction of habitual dietary patterns on the gut microbiome will lead to rational dietary manipulation to improve human health through prevention and treatment of disease.

The Impact of a Dried Fruit and Vegetable Supplement and Fiber Rich Shake on Gut and Health Parameters in Female Healthcare Workers: A Placebo-Controlled, Double-Blind, Randomized Clinical Trial.

Aim: Phytochemicals from fruits and vegetables are known to reduce inflammation and improve overall health. The objective of this study was to determine the effect of a fruit and vegetable concentrate (FVC) and high fiber component on the gut microbiome in an overweight/obese, female population. Methods: The study was a randomized, double blind, placebo-controlled trial with 57 asymptomatic, pre-menopausal, overweight/obese females between 25-50 years of age working in healthcare. Blood and fecal samples were collected before and after two, four and five months of daily supplementation. Metabolic parameters were measured, and the gut microbiome analyzed. Results: No effect was observed with FVC supplementation for blood lipids, glucose and immune parameters. There was an improvement in glucose clearance. The FVC supplement did not result in taxonomic alterations at phyla level, or changes in α or ß diversity, but reduced Bacteroides abundance and increased fecal butyrate. An additional high fiber component improved levels of health associated bacteria. Conclusion: The results suggest that a dried fruit and vegetable supplement, with a high fiber meal replacement can alter the intestinal microbiota and improve glucose clearance, suggesting that this combination of supplements can improve glucose metabolism and possibly reduce the risk of insulin resistance.

Morphological characterization of hepatic steatosis and Monte Carlo modeling of MRI signal for accurate quantification of fat fraction and relaxivity.

Chemical-shift-based fat-water MRI signal models with single- or dual-R2 * correction have been proposed for quantification of fat fraction (FF) and assessment of hepatic steatosis. However, there is a void in our understanding of which model truly mimics the underlying biophysical mechanism of steatosis on MRI signal relaxation. The purpose of this study is to morphologically characterize and build realistic steatosis models from histology and synthesize MRI signal using Monte Carlo simulations to investigate the accuracy of single- and dual-R2 * models in quantifying FF and R2 *. Fat morphology was characterized by performing automatic segmentation on 16 mouse liver histology images and extracting the radius, nearest neighbor (NN) distance, and regional anisotropy of fat droplets. A gamma distribution function (GDF) was used to generalize extracted features, and regression analysis was performed to derive relationships between FF and GDF parameters. Virtual steatosis models were created based on derived morphological and statistical descriptors, and the MRI signal was synthesized at 1.5 T and 3 T. R2 * and FF values were calculated using single- and dual-R2 * models and compared with in vivo R2 *-FF calibrations and simulated FFs. The steatosis models generated with regional anisotropy and NN distribution closely mimicked the true in vivo fat morphology. For both R2 * models, predicted R2 * values showed positive correlation with FFs, with slopes similar to those of the in vivo calibrations (P > 0.05), and predicted FFs showed excellent agreement with true FFs (R2 > 0.99), with slopes close to unity. Our study, hence, demonstrates the proof of concept for generating steatosis models from histologic data and synthesizing MRI signal to show the expected signal relaxation under conditions of steatosis. Our results suggest that a single R2 * is sufficient to accurately estimate R2 * and FF values for lower FFs, which agrees with in vivo studies. Future work involves characterizing and building steatosis models at higher FFs and testing single- and dual-R2 * models for accurate assessment of steatosis.

CRAFT for NMR lipidomics: Targeting lipid metabolism in leucine-supplemented tumor-bearing mice.

Lipid profiling by 1 H-NMR has gained increasing utility in many fields because of its intrinsically quantitative, nondestructive nature and the ability to differentiate small molecules based on their spectral location. Most nuclear magnetic resonance (NMR) techniques for metabolite quantification use frequency domain analysis that involves many user-dependent steps such as phase and baseline correction and quantification by either manual integration or peak fitting. Recently, Bayesian analysis of time-domain NMR data has been shown to reduce operator bias and increase automation in NMR spectroscopy. In this study, we demonstrate the use of CRAFT (complete reduction to amplitude-frequency table), a Bayesian-based approach to automate processing in NMR-based lipidomics using lipid standards and tissue samples of healthy and tumor-bearing mice supplemented with leucine. Complex mixtures of lipid standards were prepared and examined using CRAFT to validate it against conventional Fourier transform (FT)-NMR and derive a fingerprint to be used for analyzing lipid profiles of serum and liver samples. CRAFT and FT-NMR were comparable in accuracy, with CRAFT achieving higher correlation in quantifying several lipid species. Analysis of the serum lipidome of tumor-bearing mice revealed hyperlipidemia and no signs of hepatic triglyceride accumulation compared with that of the healthy group demonstrating that the tumor-bearing mice were in a state of precachexia. Leucine-supplementation was associated with minimal changes in the lipid profile in both tissues. In conclusion, our study demonstrates that the CRAFT method can accurately identify and quantify lipids in complex lipid mixtures and murine tissue samples and, hence, will increase automation and reproducibility in NMR-based lipidomics.

Manuka Honey Reduces NETosis on an Electrospun Template Within a Therapeutic Window.

Manuka honey, a topical wound treatment used to eradicate bacteria, resolve inflammation, and promote wound healing, is a focus in the tissue engineering community as a tissue template additive. However, its effect on neutrophil extracellular trap formation (NETosis) on a tissue engineering template has yet to be examined. As NETosis has been implicated in chronic inflammation and fibrosis, the reduction in this response within the wound environment is of interest. In this study, Manuka honey was incorporated into electrospun templates with large (1.7-2.2 µm) and small (0.25-0.5 µm) diameter fibers at concentrations of 0.1%, 1%, and 10%. Template pore sizes and honey release profiles were quantified, and the effect on the NETosis response of seeded human neutrophils was examined through fluorescence imaging and myeloperoxidase (MPO) analysis. The incorporation of 0.1% and 1% Manuka honey decreased NETosis on the template surface at both 3 and 6 h, while 10% honey exacerbated the NETosis response. Additionally, 0.1% and 1% Manuka honey reduced the MMP-9 release of the neutrophils at both timepoints. These data indicate a therapeutic window for Manuka honey incorporation into tissue engineering templates for the reduction in NETosis. Future in vivo experimentation should be conducted to translate these results to a physiological wound environment.

An Assessment of the Glyconutrient Ambrotose™ on Immunity, Gut Health, and Safety in Men and Women: A Placebo-Controlled, Double-Blind, Randomized Clinical Trial.

BACKGROUND: Certain dietary fibers have been reported to improve gut health and cellular immunity. Ambrotose is a glyconutrient supplement that contains mannose-rich polysaccharides (acemannan), reported to improve immune function. A more nutrient-dense version of this dietary supplement has been developed recently, with added aloe leaf gel powder (acemannan). The purpose of this study was to evaluate the impact of the traditional and newly developed Ambrotose products on immunity, gut health, and psychological well-being in healthy men and women. METHODS: Seventy-five men and women were randomly assigned in double-blind manner to one of five treatments, as follows: Ambrotose Advanced (AA) at 2 or 4 g daily, Ambrotose LIFE (AL) at 2 or 4 g daily, or placebo. Subjects ingested their assigned treatment daily for eight weeks. Resting heart rate, blood pressure, and measures of psychological well-being were analyzed before and after four and eight weeks of supplementation. Blood samples were collected at the same times and analyzed for zonulin, hematology measures, and cytokines-IL-6, IL-10, IL-1ß, and TNF-α (analyzed both with and without stimulation via lipopolysaccharide [LPS]). RESULTS: All Ambrotose treatments were well-tolerated. There were no differences among treatments in heart rate or blood pressure across time. Self-reported well-being scores were generally higher for the Ambrotose treatments but there were no changes of statistical significance across time (p > 0.05). Differences of statistical significance were noted for select biochemical variables, the most notable being a dramatic decrease in monocytes in the Ambrotose groups. No change was noted in the cytokine response to LPS stimulation in all groups, indicating a maintenance of a healthy immune response. Conclusion: Regular supplementation with Ambrotose is safe and can improve subclinical cellular adversity (as evidenced by a decrease in monocytes), without unnecessary activation of an immune response.

Time of Feeding Alters Obesity-Associated Parameters and Gut Bacterial Communities, but Not Fungal Populations, in C57BL/6 Male Mice.

BACKGROUND: Fasting and timed feeding strategies normalize obesity parameters even under high-fat dietary intake. Although previous work demonstrated that these dietary strategies reduce adiposity and improve metabolic health, limited work has examined intestinal microbial communities. OBJECTIVES: We determined whether timed feeding modifies the composition of the intestinal microbiome and mycobiome (yeast and fungi). METHODS: Male C57BL/6 mice were fed a high-fat diet (HF) for 6 wk. Animals were then randomly assigned to the following groups (n = 8-10/group): 1) HF ad libitum; 2) purified high-fiber diet (Daniel Fast, DF); 3) HF-time-restricted feeding (TRF) (6 h); 4) HF-alternate-day fasting (ADF); or 5) HF at 80% total caloric restriction (CR). After 8 wk, obesity and gut parameters were characterized. We also examined changes to the gut microbiome and mycobiome before, during, and following dietary interventions. RESULTS: Body mass gain was reduced with all restricted dietary groups. HF-fed microbiota displayed lower α-diversity along with reduced phylum levels of Bacteroidetes and increased Firmicutes. Animals switched from HF to DF demonstrated a rapid transition in bacterial taxonomic composition, α-, and ß-diversity that initially resembled HF, but was distinct after 4 and 8 wk of DF feeding. Time-or calorie-restricted HF-fed groups did not show changes at the phylum level, but α-diversity was increased, with specific genera altered. Six weeks of HF feeding reduced various fungal populations, particularly Alternaria, Aspergillus, Cladosporium, and Talaromyces, and increased Candida, Hanseniaspora, and Kurtzmaniella. However, 8 wk of intervention did not change the fungal populations, with the most abundant genera being Candida, Penicillium, and Hanseniaspora. CONCLUSIONS: These data suggest that timed-feeding protocols and diet composition do not significantly affect the gut fungal community, despite inducing measurable shifts in the bacterial population that coincide with improvements in metabolism.

Delta-6-desaturase (FADS2) inhibition and omega-3 fatty acids in skeletal muscle protein turnover.

Polyunsaturated fatty acids (PUFAs) are essential dietary components. They are not only used for energy, but also act as signaling molecules. The delta-6 desaturase (D6D) enzyme, encoded by the FADS2 gene, is one of two rate limiting enzymes that convert the PUFA precursors - α-linolenic (n-3) and linoleic acid (n-6) to their respective metabolites. Alterations in the D6D enzyme activity alters fatty acid profiles and are associated with metabolic and inflammatory diseases including cardiovascular disease and type 2 diabetes. Omega-3 PUFAs, specifically its constituent fatty acids DHA and EPA, are known for their anti-inflammatory ability and are also beneficial in the prevention of skeletal muscle wasting, however the mechanism for muscle preservation is not well understood. Moreover, little is known of the effects of altering the n-6/n-3 ratio in the context of a high-fat diet, which is known to downregulate protein synthesis. Twenty C57BL6 male mice were fed a high-fat lard (HFL, 45% fat (mostly lard), 35% carbohydrate and 20% protein, n-6:n-3 PUFA, 13:1) diet for 6 weeks. Mice were then divided into 4 groups (n = 5 per group): HFL- , high-fat oil- (HFO, 45% fat (mostly Menhaden oil), 35% carbohydrate and 20% protein, n-6:n-3 PUFA, 1:3), HFL+ (HFL diet plus an orally administered FADS2 inhibitor, 100 mg/kg/day), and HFO+ (HFO diet plus an orally administered FADS2 inhibitor, 100 mg/kg/day). After 2 weeks on their respective diets and treatments, animals were sacrificed and gastrocnemius muscle harvested. Protein turnover signaling were analyzed via Western Blot. 4-EBP1 and ribosomal protein S6 expression were measured. A two-way ANOVA revealed no significant change in the phosphorylation of both 4EBP-1 and ribosomal protein S6 with diet or inhibitor. There was a significant reduction in STAT3 phosphorylation with the inhibition of FADS2 (p = 0.03). Additionally, we measured markers of protein degradation through levels of FOXO phosphorylation, ubiquitin, and LC3B expression; there was a trend towards increased phosphorylation of FOXO (p = 0.08) and ubiquitinated proteins (p = 0.05) with FADS2 inhibition. LC3B expression, a marker of autophagy, was significantly higher in the HFL plus FADS2 inhibition group from all other comparisons. Lastly, we analyzed activation of mitochondrial biogenesis which is closely linked with protein synthesis through PGC1-α and Cytochrome-C expression, however no significant differences were associated with either marker across all groups. Collectively, these data suggest that the protective effects of muscle mass by omega-3 fatty acids are from inhibition of protein degradation. Our aim was to determine the role of PUFA metabolites, DHA and EPA, in skeletal muscle protein turnover and assess the effects of n-3s independently. We observed that by inhibiting the FADS2 enzyme, the protective effect of n-3s on protein synthesis and proliferation was lost; concomitantly, protein degradation was increased with FADS2 inhibition regardless of diet.

A Comparison of Dietary and Caloric Restriction Models on Body Composition, Physical Performance, and Metabolic Health in Young Mice.

Time-restricted feeding (TRF), alternate day fasting (ADF), and the dietary restriction model known as the Daniel Fast (DF; a vegan/non-processed food diet plan) have garnered attention recently as nutritional interventions to combat obesity. We compared the effects of various dietary models on body composition, physical performance, and metabolic health in C57BL/6 mice. Sixty young C57BL/6 male mice were assigned a diet of TRF, ADF, DF, caloric restriction (CR), a high-fat Western diet (HF) fed ad libitum, or standard rodent chow for eight weeks. Their body composition, run time to exhaustion, fasting glucose, insulin, and glucose tolerance test area under the glucose curve (AUC) were determined. Compared to the HF group, all groups displayed significantly less weight and fat mass gain, as well as non-significant changes in fat-free mass. Additionally, although not statistically significant, all groups displayed greater run time to exhaustion relative to the HF group. Compared to the HF group, all groups demonstrated significantly lower fasting glucose, insulin, and Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), as well as improved glucose tolerance, and the ADF group displayed the best fasting glucose and glucose tolerance results, with DF having the best HOMA-IR. All investigated fasting protocols may improve body composition, measures of insulin sensitivity, and physical performance compared to a high-fat Western diet. The DF and ADF protocols are most favorable with regards to insulin sensitivity and glucose tolerance. Since our selected dietary protocols have also been investigated in humans with success, it is plausible to consider that these dietary models could prove beneficial to men and women seeking improved body composition and metabolic health.

Isolated Rearing at Lactation Increases Gut Microbial Diversity and Post-weaning Performance in Pigs.

Environment and diet are two major factors affecting the human gut microbiome. In this study, we used a pig model to determine the impact of these two factors during lactation on the gut microbiome, immune system, and growth performance. We assigned 80 4-day-old pigs from 20 sows to two rearing strategies at lactation: conventional rearing on sow's milk (SR) or isolated rearing on milk replacer supplemented with solid feed starting on day 10 (IR). At weaning (day 21), SR and IR piglets were co-mingled (10 pens of 4 piglets/pen) and fed the same corn-soybean meal-dried distiller grain with solubles- and antibiotic-free diets for eight feeding phase regimes. Fecal samples were collected on day 21, 62, and 78 for next-generation sequencing of the V4 hypervariable region of the bacterial 16S rRNA gene. Results indicate that IR significantly increased swine microbial diversity and changed the microbiome structure at day 21. Such changes diminished after the two piglet groups were co-mingled and fed the same diet. Post-weaning growth performance also improved in IR piglets. Toward the end of the nursery period (NP), IR piglets had greater average daily gain (0.49 vs. 0.41 kg/d; P < 0.01) and average daily feed intake (0.61 vs. 0.59 kg/d; P < 0.01) but lower feed efficiency (0.64 vs. 0.68; P = 0.05). Consequently, IR piglets were heavier by 2.9 kg (P < 0.01) at the end of NP, and by 4.1 kg (P = 0.08) at market age compared to SR piglets. Interestingly, pigs from the two groups had similar lean tissue percentage. Random forest analysis showed that members of Leuconostoc and Lactococcus best differentiated the IR and SR piglets at weaning (day 21), were negatively correlated with levels of Foxp3 regulatory T cell populations on day 20, and positively correlated with post-weaning growth performance. Our results suggest that rearing strategies may be managed so as to accelerate early-life establishment of the swine gut microbiome to enhance growth performance in piglets.