The Effect of Micronutrients on Obese Phenotype of Adult Mice Is Dependent on the Experimental Environment.

The environment of the test laboratory affects the reproducibility of treatment effects on physiological phenotypes of rodents and may be attributed to the plasticity of the epigenome due to nutrient-gene-environment interactions. Here, we explored the reproducibility of adding a multi-vitamin-mineral (MVM) mix to a nutrient-balanced high-fat (HF) diet on obesity, insulin resistance (IR), and gene expression in the tissues of adult male mice. Experiments of the same design were conducted in three independent animal facilities. Adult C57BL/6J male mice were fed an HF diet for 6 weeks (diet induced-obesity model) and then continued for 9-12 weeks on the HF diet with or without 5-fold additions of vitamins A, B1, B6, B12, Zn, and 2-fold Se. The addition of the MVM affected body weight, fat mass, gene expression, and markers of IR in all three locations (p < 0.05). However, the direction of the main effects was influenced by the interaction with the experimental location and its associated environmental conditions known to affect the epigenome. In conclusion, MVM supplementation influenced phenotypes and expression of genes related to adipose function in obese adult male mice, but the experimental location and its associated conditions were significant interacting factors. Preclinical studies investigating the relationship between diet and metabolic outcomes should acknowledge the plasticity of the epigenome and implement measures to reproduce studies in different locations.

Methyl donor micronutrients, hypothalamic development and programming for metabolic disease.

Nutriture in utero is essential for fetal brain development through the regulation of neural stem cell proliferation, differentiation, and apoptosis, and has a long-lasting impact on risk of disease in offspring. This review examines the role of maternal methyl donor micronutrients in neuronal development and programming of physiological functions of the hypothalamus, with a focus on later-life metabolic outcomes. Although evidence is mainly derived from preclinical studies, recent research shows that methyl donor micronutrients (e.g., folic acid and choline) are critical for neuronal development of energy homeostatic pathways and the programming of characteristics of the metabolic syndrome in mothers and their children. Both folic acid and choline are active in one-carbon metabolism with their impact on epigenetic modification of gene expression. We conclude that an imbalance of folic acid and choline intake during gestation disrupts DNA methylation patterns affecting mechanisms of hypothalamic development, and thus elevates metabolic disease risk. Further investigation, including studies to determine translatability to humans, is required.

Micronutrients in High-Fat Diet Modify Insulin Resistance and Its Regulatory Genes in Adult Male Mice.

SCOPE: Obesity and insulin resistance (IR) are associated with epigenetic changes of gene expression. However, the relationship between micronutrients, epigenetic regulation of gene expression, and IR during development of diet-induced obesity has yet to be defined. Our objective is to describe the effect of micronutrient addition to diets on IR and its related genes during obesity development. METHODS AND RESULTS: Male C57BL/6J mice are fed a high-fat (HFD) or low-fat (LFD) diets with or without a multi-vitamin mineral mix (MVM) addition containing vitamins A, B1, B6, B12, and Zn, and Se for 9 weeks. Compared to LFD mice, HFD mice have higher body weight, IR, fasting glucose, insulin, C-peptide, leptin, and hepatic triglyceride concentrations, and dysregulated gene expression in liver, muscle, pancreas, and fat tissues (p < 0.05). The addition of MVM reduces these HFD-induced effects. HFD downregulates 27 genes associated with insulin regulation and adipose tissue function across all tissues by an average of 47% and upregulates five genes by 230% (p < 0.001). Adding MVM downregulates five genes and upregulates one in HFD-fed mice. Both HFD and MVM alter one-carbon metabolites. CONCLUSION: Addition of micronutrients to the HFD decreases IR and modifies associated gene expression in obese and lean mice.

Methylenetetrahydrofolate reductase deficiency and high-dose FA supplementation disrupt embryonic development of energy balance and metabolic homeostasis in zebrafish.

Folic acid (synthetic folate, FA) is consumed in excess in North America and may interact with common pathogenic variants in methylenetetrahydrofolate reductase (MTHFR); the most prevalent inborn error of folate metabolism with wide-ranging obesity-related comorbidities. While preclinical murine models have been valuable to inform on diet-gene interactions, a recent Folate Expert panel has encouraged validation of new animal models. In this study, we characterized a novel zebrafish model of mthfr deficiency and evaluated the effects of genetic loss of mthfr function and FA supplementation during embryonic development on energy homeostasis and metabolism. mthfr-deficient zebrafish were generated using CRISPR mutagenesis and supplemented with no FA (control, 0FA) or 100 µm FA (100FA) throughout embryonic development (0-5 days postfertilization). We show that the genetic loss of mthfr function in zebrafish recapitulates key biochemical hallmarks reported in MTHFR deficiency in humans and leads to greater lipid accumulation and aberrant cholesterol metabolism as reported in the Mthfr murine model. In mthfr-deficient zebrafish, energy homeostasis was also impaired as indicated by altered food intake, reduced metabolic rate and lower expression of central energy-regulatory genes. Microglia abundance, involved in healthy neuronal development, was also reduced. FA supplementation to control zebrafish mimicked many of the adverse effects of mthfr deficiency, some of which were also exacerbated in mthfr-deficient zebrafish. Together, these findings support the translatability of the mthfr-deficient zebrafish as a preclinical model in folate research.

Folate dose and form during pregnancy may program maternal and fetal health and disease risk.

The role of folate, in its synthetic and bioactive form, as an in utero modifier of metabolic outcomes in mothers and offspring is examined in this review. During pregnancy, a continuum of adaptive changes occurs to support maternal and fetal requirements. However, an unfavorable in utero environment may lead to permanent changes in cellular and physiological functions, adversely affecting the development of the child and postpartum health of the mother. In North American countries, synthetic folic acid (FA) is overconsumed by pregnant women, and uncertainty exists about its potential unintended health effects. Because the metabolism of FA is different than that of other folate forms, it may modulate disease risk differently. The bioactive form of folate, 5-methyltetrahydrofolic acid, has emerged as a popular alternative to FA, but clinical studies comparing their effects during pregnancy are limited. Current evidence points to the need for caution when maternal intake of either folate form exceed recommended amounts. Research directed toward defining an optimal folate dose and form for healthy pregnancy and long-term metabolic outcomes in mothers and children is urgently needed.

Age and Sex Interact to Determine the Effects of Commonly Consumed Dairy Products on Postmeal Glycemia, Satiety, and Later Meal Food Intake in Adults.

BACKGROUND: Dairy consumption reduces postprandial glycemia and appetite when consumed with carbohydrates. OBJECTIVES: The objective was to test the effects of frequently consumed dairy products, age, and sex on glycemia, appetite, and food intake. METHODS: In a randomized, unblinded, crossover design, 30 older [60-70 y; BMI (kg/m2): 18.5-29.9] and 28 young (20-30 y; BMI: 18.5-24.9) adults consumed 500 mL of a calorie-free control (water), skim milk and whole milk, 350 g Greek yogurt, and 60 g cheddar cheese. Food intake at an ad libitum meal was measured 120 min later. Glycemia, appetite, and gastric hormone responses were measured premeal (15-120 min), within-meal (120-140 min), and postmeal (140-170 min). Effects of treatment, age, and sex and their interactions were analyzed using ANOVA followed by Tukey's post hoc test. RESULTS: All forms of dairy, compared with water, decreased postmeal glycemia, premeal appetite, and meal intake (P < 0.0001). Premeal glucose, insulin, and glucagon-like peptide 1 increased, and ghrelin decreased, but effects of dairy differed with age and sex. Older adults had 10% higher pre- and postmeal glucose (P < 0.01). Premeal appetite suppression per 100 kcal of treatments was more after yogurt than other dairy, but overall appetite suppression was less in older adults than in young adults and in males than in females (P < 0.05). Pizza intake was reduced by 175 kcal after yogurt and cheese and by 82 kcal after milks compared to water (P < 0.001). Mealtime reduction for treatment calories averaged 62% after yogurt and cheese but was less at 33% after milks (P < 0.05). Compensation was less in older (33%) than in young (63%) adults (P < 0.03). CONCLUSIONS: Dairy products consumed in usual forms before a meal stimulate metabolic responses leading to reduced premeal appetite, later food intake, and postmeal glycemia, but their effects differ in magnitude and with the sex and age of adults.

High Choline Intake during Pregnancy Reduces Characteristics of the Metabolic Syndrome in Male Wistar Rat Offspring Fed a High Fat But Not a Normal Fat Post-Weaning Diet.

Maternal choline intakes are below recommendations, potentially impairing the child's later-life metabolic health. This study aims to elucidate the interaction between the choline content of the gestational diet (GD) and fat content of the post-weaning diet (PWD) on metabolic phenotype of male Wistar rats. Pregnant Wistar rats were fed a standard rodent diet (AIN-93G) with either recommended choline (RC, 1 g/kg diet choline bitartrate) or high choline (HC, 2.5-fold). Male pups were weaned to either a normal (16%) fat (NF) or a high (45%) fat (HF) diet for 17 weeks. Body weight, visceral adiposity, food intake, energy expenditure, plasma hormones, triglycerides, and hepatic fatty acids were measured. HC-HF offspring had 7% lower body weight but not food intake, and lower adiposity, plasma triglycerides, and insulin resistance compared to RC-HF. They also had increased hepatic n-3 fatty acids and a reduced n-6/n-3 and C 18:1 n-9/C18:0 ratios. In contrast, HC-NF offspring had 6-8% higher cumulative food intake and body weight, as well as increased leptin and elevated hepatic C16:1 n-7/C16:0 ratio compared to RC-NF. Therefore, gestational choline supplementation associated with improved long-term regulation of several biomarkers of the metabolic syndrome in male Wistar rat offspring fed a HF, but not a NF, PWD.

High Intakes of [6S]-5-Methyltetrahydrofolic Acid Compared with Folic Acid during Pregnancy Programs Central and Peripheral Mechanisms Favouring Increased Food Intake and Body Weight of Mature Female Offspring.

Supplementation with [6S]-5-methyltetrahydrofolic acid (MTHF) is recommended as an alternative to folic acid (FA) in prenatal supplements. This study compared equimolar gestational FA and MTHF diets on energy regulation of female offspring. Wistar rats were fed an AIN-93G diet with recommended (2 mg/kg diet) or 5-fold (5X) intakes of MTHF or FA. At weaning, female offspring were fed a 45% fat diet until 19 weeks. The 5X-MTHF offspring had higher body weight (>15%), food intake (8%), light-cycle energy expenditure, and lower activity compared to 5X-FA offspring (p < 0.05). Both the 5X offspring had higher plasma levels of the anorectic hormone leptin at birth (60%) and at 19 weeks (40%), and lower liver weight and total liver lipids compared to the 1X offspring (p < 0.05). Hypothalamic mRNA expression of leptin receptor (ObRb) was lower, and of suppressor of cytokine signaling-3 (Socs3) was higher in the 5X-MTHF offspring (p < 0.05), suggesting central leptin dysregulation. In contrast, the 5X-FA offspring had higher expression of genes encoding for dopamine and GABA- neurotransmitter receptors (p < 0.01), consistent with their phenotype and reduced food intake. When fed folate diets at the requirement level, no differences were found due to form in the offspring. We conclude that MTHF compared to FA consumed at high levels in the gestational diets program central and peripheral mechanisms to favour increased weight gain in the offspring. These pre-clinical findings caution against high gestational intakes of folates of either form and encourage clinical trials examining their long-term health effects when consumed during pregnancy.

The effect of dairy products and non-dairy snacks on food intake, subjective appetite and cortisol levels in children: a randomized control study.

Dairy snacks are available in various physical forms and their consumption is linked to improved metabolic health. The objective of this study was to determine the effect of dairy snacks of different physical forms on short-term food intake (FI), subjective appetite, and the stress hormone, cortisol, in children. Following a repeated-measures crossover design, 40 children aged 9-14 years randomly consumed 1 of 5 isoenergetic (180 kcal) snacks per study session. These snacks included solid (potato chips, cookies, and cheese), semi-solid (Greek yogurt), and fluid (2% fat milk) snacks. FI was measured 120 min after snack consumption. Subjective appetite was measured at 0 (immediately before the snack), 15, 30, 45, 60, 90, and 120 min. Salivary cortisol (n = 18) was measured after the Greek yogurt and cookie snacks at 0, 30, 60, 90, and 120 min. FI did not differ between snacks (P = 0.15). The Greek yogurt (P < 0.0001) and cheese (P = 0.0009) snacks reduced average appetite compared with the 2% fat milk snack. Salivary cortisol levels were not affected by snack (P = 0.84). This study demonstrates that dairy snacks are as effective as other popular snacks at influencing subsequent FI. However, solid and semi-solid dairy snacks are more effective at repressing subjective appetite than a fluid dairy snack. Registered at ClinicalTrials.gov (NCT02484625). Novelty: Milk, Greek yogurt and cheese have a similar effect on short-term food intake in children as popular potato chips and cookie snacks. Solid, semi-solid and liquid snacks have a similar effect on short-term food intake in children.

Choline and Folic Acid in Diets Consumed during Pregnancy Interact to Program Food Intake and Metabolic Regulation of Male Wistar Rat Offspring.

BACKGROUND: North American women consume high folic acid (FA), but most are not meeting the adequate intakes for choline. High-FA gestational diets induce an obesogenic phenotype in rat offspring. It is unclear if imbalances between FA and other methyl-nutrients (i.e., choline) account for these effects. OBJECTIVE: This study investigated the interaction of choline and FA in gestational diets on food intake, body weight, one-carbon metabolism, and hypothalamic gene expression in male Wistar rat offspring. METHODS: Pregnant Wistar rats were fed an AIN-93G diet with recommended choline and FA [RCRF; 1-fold, control] or high (5-fold) FA with choline at 0.5-fold [low choline and high folic acid (LCHF)], 1-fold [recommended choline and high folic acid (RCHF)], or 2.5-fold [high choline and high folic acid (HCHF)]. Male offspring were weaned to an RCRF diet for 20 wk. Food intake, weight gain, plasma energy-regulatory hormones, brain and plasma one-carbon metabolites, and RNA sequencing (RNA-seq) in pup hypothalamuses were assessed. RESULTS: Adult offspring from LCHF and RCHF, but not HCHF, gestational diets had 10% higher food intake and weight gain than controls (P < 0.01). HCHF newborn pups had lower plasma insulin and leptin compared with LCHF and RCHF pups (P < 0.05), respectively. Pup brain choline (P < 0.05) and betaine (P < 0.01) were 22-33% higher in HCHF pups compared with LCHF pups; methionine was ∼23% lower after all high FA diets compared with RCRF (P < 0.01). LCHF adult offspring had lower brain choline (P < 0.05) than all groups and lower plasma 5-methyltetrahydrofolate (P < 0.05) than RCRF and RCHF groups. HCHF adult offspring had lower plasma cystathionine (P < 0.05) than LCHF adult offspring and lower homocysteine (P < 0.01) than RCHF and RCRF adult offspring. RNA-seq identified 144 differentially expressed genes in the hypothalamus of HCHF newborns compared with controls. CONCLUSIONS: Increased choline in gestational diets modified the programming effects of high FA on long-term food intake regulation, plasma energy-regulatory hormones, one-carbon metabolism, and hypothalamic gene expression in male Wistar rat offspring, emphasizing a need for more attention to the choline and FA balance in maternal diets.

An examination of contributions of animal- and plant-based dietary patterns on the nutrient quality of diets of adult Canadians.

Dietary guidance and Canada's 2019 Food Guide encourage increased consumption of plant-based foods as a source of dietary protein. However, there is an absence of recent data on protein and nutrient intakes and quality of Canadian dietary patterns that might occur with increased plant protein intakes. This study compared food sources and nutrient intakes of Canadian adults within groups of increasing plant protein-containing diets. The CCHS 2015 Public-Use Microdata File of single 24-hour dietary recalls of males and females ≥19 years (n = 6498) or ≥70 years (n = 1482) were examined. Respondents were allocated into 4 groups defined by their protein intake percentage coming from plant-based foods (i.e., group 1: 0-24.9%, group 2: 25-49.9%, group 3: 50-74.9%, group 4: 75-100%). Protein intake in adults averaged 63.3% animal and 36.7% plant protein. Where plant protein contributed >50% protein, higher intakes of carbohydrate, dietary fibre, folate, dietary folate equivalents, iron and magnesium (p < 0.001) but lower intakes of total and saturated fat, protein, vitamin D, vitamin B12, riboflavin and niacin (p < 0.0001) were reported. In contrast, group 1 had higher total and saturated fat, protein, vitamin B12, thiamin, niacin, and zinc, but lower carbohydrate, dietary fibre, and magnesium. Balancing plant- with animal-based protein foods leads to healthier dietary patterns with more favourable nutritional properties when compared with diets based on either high animal or high plant protein content. Novelty: Combinations of animal- and plant-based proteins improve nutrient quality of Canadian diets. The source of protein influences diet quality.

Faba bean meal, starch or protein fortification of durum wheat pasta differentially influence noodle composition, starch structure and in vitro digestibility.

Faba bean (Vicia faba L.) flour, starch concentrate (60% starch), protein concentrate (~60% protein) and protein isolate (~85% protein) were added to replace one-quarter of durum wheat semolina to enrich the nutritional quality and physiological functions of durum wheat (Triticum turgidum L.) pasta. The raw pasta samples prepared with protein concentrate or isolate had higher (p ≤ 0.001) protein and lower (p ≤ 0.001) total starch concentrations, along with increased total dietary fiber and slowly digestible starch (p ≤ 0.001) than durum wheat semolina control or those with added whole faba-bean flour or isolated starch. The faba bean fortified pasta had altered starch with increased proportion of medium B-type glucan chains and long C-type glucan chains, reduced starch digestibility and were associated with glycaemia related effects in the human diet. The faba bean fortified pasta had increased protein and dietary fiber that influenced food intake and satiety. The results suggest differential contributions of food ingredients in human health outcomes.

[6S]-5-Methyltetrahydrofolic Acid and Folic Acid Pregnancy Diets Differentially Program Metabolic Phenotype and Hypothalamic Gene Expression of Wistar Rat Dams Post-Birth.

[6S]-5-methyltetrahydrofolic acid (MTHF) is a proposed replacement for folic acid (FA) in diets and prenatal supplements. This study compared the effects of these two forms on maternal metabolism and hypothalamic gene expression. Pregnant Wistar rats received an AIN-93G diet with recommended FA (1X, 2 mg/kg, control), 5X-FA or equimolar levels of MTHF. During lactation they received the control diet and then a high fat diet for 19-weeks post-weaning. Body weight, adiposity, food intake, energy expenditure, plasma hormones, folate, and 1-carbon metabolites were measured. RNA-sequencing of the hypothalamus was conducted at parturition. Weight-loss from weaning to 1-week post-weaning was less in dams fed either form of the 5X vs. 1X folate diets, but final weight-gain was higher in 5X-MTHF vs. 5X-FA dams. Both doses of the MTHF diets led to 8% higher food intake and associated with lower plasma leptin at parturition, but higher leptin at 19-weeks and insulin resistance at 1-week post-weaning. RNA-sequencing revealed 279 differentially expressed genes in the hypothalamus in 5X-MTHF vs. 5X-FA dams. These findings indicate that MTHF and FA differ in their programing effects on maternal phenotype, and a potential adverse role of either form when given at the higher doses.

Role of Amino Acids in Blood Glucose Changes in Young Adults Consuming Cereal with Milks Varying in Casein and Whey Concentrations and Their Ratio.

BACKGROUND: Increasing the total protein content and reducing the casein to whey ratio in milks consumed with breakfast cereal reduce postprandial blood glucose (BG). OBJECTIVES: We aimed to explore associations between plasma amino acids (AAs), BG, and glucoregulatory hormones. METHODS: In this repeated-measures design, 12 healthy adults consumed cereal (58 g) and milks (250 mL) with 3.1 wt% or high 9.3 wt% protein concentrations and with casein to whey ratios of either 80:20 or 40:60. Blood was collected at 0, 30, 60, 120, 140, 170, and 200 min for measurement of the primary outcome, BG, and for the exploratory outcomes such as plasma AA, gastric emptying, insulin (INS), and glucoregulatory hormones. Measures were made prior to and after an ad libitum lunch at 120 min. Exploratory correlations were conducted to determine associations between outcomes. RESULTS: Pre-lunch plasma AA groups [total (TAA), essential (EAA), BCAA, and nonessential (NEAA)] were higher after 9.3 wt% than 3.1 wt% milks by 12.7%, 21.4%, 20.9%, and 7.6%, respectively (P ≤ 0.05), while post-lunch AA groups were higher by 10.9%, 19.8%, 18.8%, and 6.0%, respectively (P ≤ 0.05). Except for NEAA, pre-lunch AAs were higher after 40:60 than 80:20 ratio milks by 4.5%, 8.3%, and 9.3% (P ≤ 0.05). When pooled by all treatments, pre-lunch AA groups associated negatively with BG (r/ρ ≥ -0.45, P ≤ 0.05), but post-lunch only TAA and NEAA correlated (r ≥ -0.37, P < 0.05). Pre-lunch BG was inversely associated with Leu, Ile, Lys, Met, Thr, Cys-Cys, Asn, and Gln (r/ρ ≥ -0.46, P ≤ 0.05), but post-lunch, only with Thr, Ala, and Gly (r ≥ -0.50, P ≤ 0.05). Pre-lunch associations between AA groups and INS were not found. CONCLUSIONS: Protein concentration and the ratio of casein to whey in milks consumed at breakfast with cereal affect plasma AA concentrations and their associations with decreased BG. The decrease in BG could be explained by INS-independent mechanisms. This trial was registered at www.clinicaltrials.gov as NCT02471092.

Folic acid content of diet during pregnancy determines post-birth re-set of metabolism in Wistar rat dams.

Maternal metabolism begins to return to homeostasis (re-set) following birth and is accelerated by lactation. Delay in metabolic re-set may contribute to postpartum weight retention and later-life metabolic consequences. Folic acid (FA) is essential during pregnancy but inadequate intakes may alter 1-carbon metabolism, consequently affecting energy homeostatic systems. Our objectives were to examine the effects of FA content 1)below and 2)above requirements during pregnancy on the re-set of body weight, markers of hepatic 1-carbon metabolism and central and peripheral energy metabolic pathways in Wistar rat mothers early post-weaning (PW) compared to pregnant controls. Pregnant Wistar rats were fed an AIN-93G diet with FA at 0X, 1X (control, 2 mg FA/kg) or a range above requirements at 2.5X, 5X or 10X recommended levels then the control diet during lactation up to 1 week PW. Dams fed below (0X) or above (5X and 10X) FA requirements had delayed weight-loss from weaning up to 1 week PW, higher plasma insulin and HOMA-IR and changes in glucose and lipid metabolism-regulating genes in muscle, but not liver or adipose tissue compared to controls. Expression of folate-related genes in liver were lower in high FA fed dams. Central food intake neurons were not affected by FA diets. In conclusion, intakes of FA below (0X) or above (5X, 10X) requirements during pregnancy delayed weight-loss, dysregulated 1-carbon pathways in the liver and peripheral energy metabolic pathways in the Wistar rat mother up to 4 weeks after dietary exposure; potentially programming long-term negative metabolic effects and that of her future offspring.

Effects of cultured dairy and nondairy products added to breakfast cereals on blood glucose control, satiation, satiety, and short-term food intake in young women.

Breakfast cereals are often consumed with dairy products or nondairy alternatives; however, the effect of the combination on blood glucose and food intake control is not well investigated. In a randomized, crossover study, 24 healthy women (age: 22.7 ± 2.5 years; body mass index: 22.1 ± 1.5 kg/m2) consumed, to satiation, 1 of 3 treatments: Greek yogurt with granola (150 kcal, 9.2 g protein, 2.6 g fat, 2.0 g dietary fibre, and 21.5 g available carbohydrate/100 g); cultured coconut product with granola (146 kcal, 3.2 g protein, 3.2 g fat, 5.6 g dietary fibre, and 21.9 g available carbohydrate/100 g); or water control. The data were analyzed with repeated-measures ANOVA. The 2 h blood glucose iAUC was 52% lower after the dairy compared with nondairy treatment (P < 0.0001). While there were no differences in food intake between the caloric treatments consumed to satiation, protein intake was 3 times higher and fibre intake was 4 times lower after the dairy compared with nondairy treatment. Both caloric treatments resulted in similar suppression of ad libitum food intake at 2 h (P < 0.003) and subjective appetite over 2 h (P < 0.0001) compared with water. The cumulative food intake over 2 h was lower after water (P < 0.05). The 1.8-fold increase in postprandial insulin after dairy compared with nondairy treatment may explain the reduction in blood glucose without an increase in subsequent energy intake. Novelty Blood glucose in young females is lower after a breakfast with granola in a high-protein cultured dairy than when in a high-fibre nondairy cultured product. Subjective appetite over 2 h and food intake 2 h later was similarly lower after both breakfasts but cumulative intake was higher compared with breakfast skipping.

Ethanolamides of essential α-linolenic and linoleic fatty acids suppress short-term food intake in rats.

Food source has a significant impact on levels of fatty acids and their derivatives, fatty acid ethanolamides (FAEs), in the small intestine and brain. Among non-essential fatty acids, oleic acid and its FAE acutely reduce food intake. However, effects of the essential α-linolenic acid, linoleic acid, and their FAEs on appetite regulation remain undefined. This study tested the hypothesis that α-linolenic acid and linoleic acid mediate acute suppression of food intake through their corresponding FAEs, α-linolenoylethanolamide and linoleoylethanolamide, respectively. To allow for the differentiation of the effects of FAEs and their parent fatty acids, male Wistar rats were injected intraperitoneally with α-linolenic acid, linoleic acid, α-linolenoylethanolamide and linoleoylethanolamide after a 12-hour overnight fast. Short-term food intake, plasma and brain FAE status, and plasma concentrations of insulin and leptin were measured to determine whether these hormones mediate the anorectic effect of FAEs. Both ethanolamides, but not their parent fatty acids, acutely suppressed food intake up to one hour post-treatment and this effect was independent of insulin and leptin hormones. In conclusion, essential α-linolenic and linoleic fatty acids mediate acute suppression of food intake through their corresponding FAEs. These findings may aid in the further research of FAEs as potential therapeutic agents for the management and treatment of obesity.

Maternal Choline Intake Programs Hypothalamic Energy Regulation and Later-Life Phenotype of Male Wistar Rat Offspring.

SCOPE: High-folic-acid diets during pregnancy result in obesity in the offspring, associated with altered DNA-methylation of hypothalamic food intake neurons. Like folic acid, the methyl-donor choline modulates foetal brain development, but its long-term programing effects on energy regulation remain undefined. This study aims to describe the effect of choline intake during pregnancy on offspring phenotype and hypothalamic energy-regulatory mechanisms. METHODS AND RESULTS: Wistar rat dams are fed an AIN-93G diet with recommended choline (RC, 1 g kg-1 diet), low choline (LC, 0.5-fold), or high choline (HC, 2.5-fold) during pregnancy. Male pups are terminated at birth and 17 weeks post-weaning. Brain 1-carbon metabolites, body weight, food intake, energy expenditure, plasma hormones, and protein expression of hypothalamic neuropeptides are measured. HC pups have higher expression of the orexigenic neuropeptide-Y neurons at birth, consistent with higher cumulative food intake and body weight gain post-weaning compared to RC and LC offspring. LC pups have lower leptin receptor expression at birth and lower energy expenditure and activity during adulthood. CONCLUSION: Choline content of diets that are consumed by rats during pregnancy affects the later-life phenotype of offspring, associated with altered in utero programing of hypothalamic food intake regulation.

Gestational folic acid content alters the development and function of hypothalamic food intake regulating neurons in Wistar rat offspring post-weaning.

Background: Folic acid plays an important role in early brain development of offspring, including proliferation and differentiation of neural stem cells known to impact the function of food intake regulatory pathways. Excess (10-fold) intakes of folic acid in the gestational diet have been linked to increased food intake and obesity in male rat offspring post-weaning.Objective: The present study examined the effects of folic acid content in gestational diets on the development and function of two hypothalamic neuronal populations, neuropeptide Y (NPY) and pro-opiomelanocortin (POMC), within food intake regulatory pathways of male Wistar rat offspring at birth and post-weaning.Results: Folic acid fed at 5.0-fold above recommended levels (5RF) to Wistar dams during pregnancy increased the number of mature NPY-positive neurons in the hypothalamus of male offspring, compared to control (RF), 0RF, 2.5RF, and 10RF at birth. Folic acid content had no effect on expression and maturation of POMC-positive neurons. Body weight and food intake were higher in all treatment groups (2.5-, 5.0-, and 10.0-fold folic acid) from birth to 9 weeks post-weaning compared to control. Increased body weight and food intake at 9-weeks post-weaning were accompanied by a reduced activation of POMC neurons in the arcuate nucleus (ARC).Conclusion: Gestational folic acid content modulates expression of mature hypothalamic NPY-positive neurons at birth and activation of POMC-positive neurons at 9-weeks post-weaning in the ARC of male Wistar rat offspring which may contribute to higher body weight and food intake later in life.

Correlating in vitro digestion viscosities and bioaccessible nutrients of milks containing enhanced protein concentration and normal or modified protein ratio to human trials.

This work compared in vitro and in vivo digestion of breakfast cereal with milks containing high protein concentration (9.3 wt%) and the normal protein ratio (80 casein : 20 whey) or a modified ratio (40 casein : 60 whey) and with a water-permeate control. The in vivo study indicated that high protein concentration and modified ratio in milks delays the postprandial appearance of blood glucose (BG) and amino acids due to delayed gastric emptying and hormonal responses. However, the role of viscosity and/or protein structure during digestion was not examined. Therefore, milks and the control were digested in vitro (oral (O, 2 min), gastric (G, 62 min) and duodenal (D, 92 min)) to determine viscosity, particle disintegration, protein solubility and hydrolysis, and the bioaccessibilities of sugars and total amino acids (TAA). The normal ratio (80 : 20) treatment demonstrated higher structural viscosity during digestion (P < 0.05) due to the formation of casein aggregates and interaction with cereal and greater TAA (mg per g protein of undigested breakfast) caused by gastric hydrolysis (DH%; P = 0.01). Overall, there were no treatment differences for disintegration, solubility and d-glucose. Protein-containing treatments inhibited amylolysis and lowered reducing sugars (mg g-1 available carbohydrates of undigested breakfast) compared to the control. Similar trends were observed between higher viscosity (Pa s) during gastric stage and slower in vivo gastric emptying (paracetamol, mmol L-1). Also, protein treatments inhibited amylolysis and lowered reducing sugar (mg g-1 of carbohydrates) and may have contributed to lowered BG (mmol L-1 g-1 of carbohydrates) after the duodenal phase. However, increased viscosity, elicited by higher proportions of casein, did not inhibit starch hydrolysis and appearance of BG. In vitro systems provide similar trends in biomarkers to in vivo studies and can be used to answer specific physiological questions.