Peptide YY Concentrations Research Articles

Metformin improves blood glucose by increasing incretins independent of changes in gluconeogenesis in youth with type 2 diabetes.

Metformin is the only approved oral agent for youth with type 2 diabetes but its mechanism of action remains controversial. Recent data in adults suggest a primary role for the enteroinsular pathway, but there are no data in youth, in whom metformin efficacy is only ~50%. Our objectives were to compare incretin concentrations and rates of glucose production and gluconeogenesis in youth with type 2 diabetes before and after short-term metformin therapy compared with peers with normal glucose tolerance (NGT). This is a case-control observational study in youth with type 2 diabetes who were not on metformin (n = 18) compared with youth with NGT (n = 10) who were evaluated with a 2day protocol. A 75g OGTT was administered to measure intact glucagon-like 1 peptide (iGLP-1), gastric inhibitory polypeptide (GIP) and peptide YY (PYY). Insulinogenic index (IGI) and whole-body insulin sensitivity were calculated using glucose and insulin levels from the OGTT. Basal rates of gluconeogenesis (2H2O), glucose production ([6,6-2H2]glucose) and whole-body lipolysis ([2H5]glycerol) were measured after an overnight fast on study day 2. Youth with type 2 diabetes (n = 9) were subsequently evaluated with an identical 2day protocol after 3months on the metformin study. Compared with individuals with NGT, those with type 2 diabetes had higher fasting (7.8 ± 2.5 vs 5.1 ± 0.3mmol/l, mean ± SD p = 0.002) and 2h glucose concentrations (13.8 ± 4.5 vs 5.9 ± 0.9mmol/l, p = 0.001), higher rates of absolute gluconeogenesis (10.0 ± 1.7 vs 7.2 ± 1.1μmol [kg fat-free mass (FFM)]-1min-1, p < 0.001) and whole-body lipolysis (5.2 ± 0.9 vs 4.0 ± 1.4μmol kgFFM-1min-1, p < 0.01), but lower fasting iGLP-1 concentrations (0.5 ± 0.5 vs 1.3 ± 0.7pmol/l, p < 0.01). Metformin decreased 2h glucose (pre metformin 11.4 ± 2.8 vs post metformin 9.9 ± 1.9mmol/l, p = 0.04) and was associated with ~20-50% increase in IGI (median [25th-75th percentile] pre 1.39 [0.89-1.47] vs post 1.43 [0.88-2.70], p = 0.04), fasting iGLP-1 (pre 0.3 ± 0.2 vs post 1.0 ± 0.7pmol/l, p = 0.02), 2h iGLP (pre 0.4 ± 0.2 vs post 1.2 ± 0.9pmol/l, p = 0.06), fasting PYY (pre 6.3 ± 2.2 vs post 10.5 ± 4.3pmol/l, p < 0.01) and 2h PYY (pre 6.6 ± 2.9 vs post 9.0 ± 4.0pmol/l, p < 0.01). There was no change in BMI, insulin sensitivity or GIP concentrations pre vs post metformin. There were no differences pre vs post metformin in rates of glucose production (15.0 ± 3.9 vs 14.9 ± 2.2μmol kgFFM-1min-1, p = 0.84), absolute gluconeogenesis (9.9 ± 1.8 vs 9.7 ± 1.7μmol kgFFM-1min-1, p = 0.76) or whole-body lipolysis (5.0 ± 0.7 vs 5.3 ± 1.3μmol kgFFM-1min-1, p = 0.20). Post metformin iGLP-1 and PYY concentrations in youth with type 2 diabetes were comparable to levels in youth with NGT. Overall, the improved postprandial blood glucose levels and increase in incretins observed in the absence of changes in insulin sensitivity and gluconeogenesis, support an enteroinsular mechanistic pathway in youth with type 2 diabetes treated with short-term metformin.

Enolase inhibition alters metabolic hormones and inflammatory factors to promote neuroprotection in spinal cord injury

Enolase inhibition is a potential therapeutic strategy currently being investigated for treatment of spinal cord injury (SCI) as it reduces pro-inflammatory cytokines and chemokines, alters metabolic factors, and reduces gliosis in acute SCI. Herein, the role of enolase in SCI has been examined to better understand the effects of this enzyme on inflammation, metabolic hormones, glial cell activation, and neuroprotection under these shorter injury conditions. Immunohistochemical analyses of inflammatory markers vimentin, Cox-2, and caspase-1 indicated that enolase inhibition attenuated the elevated levels of inflammation seen following SCI. Iba1, GFAP, NFP, and CSPG staining indicated that enolase inhibition with prolonged administration of ENOblock reduced microglia/astrocyte activation and lead to enhanced neuroprotection in SCI. An analysis of metabolic hormones revealed that ENOblock treatment significantly upregulated plasma concentrations of peptide YY, glucagon-like peptide 1, glucose-dependent insulinotropic peptide, glucagon, and insulin hormones as compared to vehicle-treated controls (Mann-Whitney, p ≤ 0.05). ENOblock did not have a significant effect on plasma concentrations of pancreatic polypeptide. Interestingly, ENOblock treatment inhibited chondroitin sulfate proteoglycan (CSPG), which is produced by activated glia and serves to block regrowth of axons across the lesion site following injury. An increased level of NeuN and MBP with reduced caspase-1 was detected in SCI tissues after ENOblock treatment, suggesting preservation of myelin and induction of neuroprotection. ENOblock also induced improved motor function in SCI rats, indicating a role for enolase in modulating inflammatory and metabolic factors in SCI with important implications for clinical consideration.

No Changes In Appetite Stimulating Hormones Following Swimming And Cycling Exercise Interventions

Swimming is a favorable and ideal modality of exercise for individuals with obesity and arthritis as it encompasses a minimal weight-bearing stress and a reduced heat load. However, the available evidence indicates that regular swimming may not be effective in reducing body weight and body fatness. A current hypothesis is that exercise in cold water somehow stimulates appetite. PURPOSE: We determined the effect of swimming exercise training on fasting concentrations of ghrelin, insulin, leptin, and peptide YY in obese individuals with osteoarthritis. Cycling training was included as a non-weight bearing land-based comparison group. METHODS: Thirty-nine obese participants with osteoarthritis (age=59±1 years, BMI=33±1 kg/m2) were randomly assigned to 12 weeks of supervised swimming training (N=19) or cycling training (N=20). In the initial few weeks, participants exercised for 20-30 minutes/day, 3 days/week, at an exercise intensity of 40-50% of heart rate reserve (HRR). Subsequently, the intensity and duration of exercise were progressively increased to 40-45 minutes/day, 3 days/week, at an intensity of 60-70% of HRR. Fasting blood samples were analyzed for ghrelin, insulin, leptin, and peptide YY concentrations using ELISAs. RESULTS: There were no group differences in body weight, BMI, or appetite stimulating hormones prior to the exercise interventions. Fasting plasma concentrations of ghrelin (37±8 vs. 42±11 pg/ml), insulin (1,176±424 vs. 1,179±442 pg/ml), leptin (20,200±2,891 vs. 16,617±2,734 pg/ml), and peptide YY (51±6 vs. 54±7 pg/ml) did not change with the swimming exercise intervention (all p>0.05). Similarly, cycling exercise had no effect on ghrelin (36±10 vs. 44±8 pg/ml), insulin (978±321 vs. 964±311 pg/ml), leptin (29,261±5,438 vs. 26,308±4,771 pg/ml), or peptide YY (58±15 vs. 63±16 pg/ml) concentrations (all p>0.05). CONCLUSIONS: Our present results indicate that fasting levels of appetite stimulating hormones did not change with 12 weeks of swimming exercise intervention in obese participants with osteoarthritis and that there were no group differences in changes in these hormones between swimming and cycling exercise interventions.

Effect of Bacillus–direct-fed microbial on leaky gut, serum peptide YY concentration, bone mineralization, and ammonia excretion in neonatal female turkey poults fed with a rye-based diet

Rye is high in nonstarch polysaccharides (NSP), a complex carbohydrate which cannot be digested by poultry as they lack the endogenous enzymes to do so. Exogenous carbohydrases must therefore be supplemented to avoid the antinutritional effects associated with a high NSP diet. The objectives of the present study were to evaluate the effects of a rye-based diet with and without supplementation of a Bacillus direct-fed microbial (DFM) on body weight, bone mineralization, and leaky gut, as well as its role on influencing serum concentrations of peptide YY (PPY) and the ammonia concentration in turkey manure. Two independent trials were conducted. In each experiment, day-of-hatch female turkey poults were neck tagged and randomly assigned to either a control rye-based diet or a rye-based diet supplemented with the DFM (n = 25 birds/group). At 10 days-of-age, poults in both groups were administered with an appropriate dose of fluorescein isothiocyanate-dextran (FITC-d) by oral gavage. One hour later, all poults were euthanized. Blood was collected to evaluate serum FITC-d and PPY concentrations. Furthermore, in Trial 2 only, both tibias were removed for assessment of bone parameters, and turkey manure was collected to evaluate physicochemical analysis. In both trials, poults treated with the DFM showed a significant increase (P < 0.05) in body weight and body weight gain as compared with control nontreated poults. Poults that received the DFM also had a significant reduction in serum levels of PPY and FITC-d when compared with control nontreated poults. In Trial 2, turkeys treated with the DFM had a substantial increase in tibia strength, tibia diameter, total ash, calcium, and phosphorus when compared with control nontreated turkeys. Their manure was also shown to have a significant reduction in the concentration of ammonia. This is the first report of a commercial DFM reducing the concentration of this compound in turkey manure. In summary, the results of the present study confirm that turkeys fed with a rye-based diet have a significant increase in gut permeability, a reduced body weight, and decreased bone mineralization when compared with turkeys fed with the DFM. Turkeys that received the rye-based diet supplemented with the Bacillus-DFM also had a significant reduction in the serum concentration of PPY when compared with control turkeys. This finding suggests a possible prebiotic effect of rye, warranting future studies to test this effect. Further studies to evaluate the microbiota diversity, as well as the concentration of ceca short-chain fatty acids, are also necessary to confirm the reliability of PPY as a potential metabolomic biomarker in poultry.

MON-321 AgRP and Food Cravings Decrease with Treatment of Cushing’s Disease

Cushing’s disease (CD) is characterized by chronic exposure to excess glucocorticoids due to an ACTH-producing tumor. Obesity is a prominent feature of CD, although the mechanisms of weight gain have not been completely elucidated. In some patients, obesity persists despite appropriate medical or surgical treatment of CD and normalization of cortisol levels (1). Few studies have followed patients prospectively to understand the effect of CD remission and cortisol normalization on appetite and body weight. Previous studies have not shown a correlation between appetite or food cravings and circulating total peptide YY (PYY), ghrelin, or leptin concentrations, leading to interest in other hormones which may regulate appetite in CD (2). One of these is the neuropeptide Agouti-related protein (AgRP). AgRP is known to promote appetite and decrease energy expenditure by acting as a melanocortin antagonist at the level of the hypothalamus. Plasma AgRP may be elevated in patients with active CD and decreases with normalization of cortisol levels (3). We sought to determine if AgRP may play a role in regulating appetite or food cravings in CD. Plasma AgRP was measured before and prospectively after treatment in 19 patients with CD. Patients completed surveys on appetite and food cravings at these same time points. As expected, AgRP significantly decreased following treatment for CD, with mean AgRP before treatment 128.72 pg/mL (SD 55.41) and mean AgRP after treatment 75.23 pg/mL (SD 23.46). Using a paired t-test, the mean difference of 53.5 pg/mL was significant (p=0.0006). In addition, there were significant decreases in BMI, weight, and waist circumference with CD treatment. We found that plasma AgRP concentrations did not correlate with an 8-question visual analogue scale (VAS) used to assess hunger and satiety. However, treatment of CD significantly reduced Trait Food Craving Questionnaire scores in parallel with circulating AgRP levels using a one-way analysis of variance (p=0.004). Our data suggest that AgRP may play a role in food craving, rather than appetite, in patients with CD. Further research may clarify the relationship between AgRP and food cravings in CD patients before and after treatment.

Plasma Peptide Concentrations and Peptide-Reactive Immunoglobulins in Patients with Eating Disorders at Inclusion in the French EDILS Cohort (Eating Disorders Inventory and Longitudinal Survey).

Eating disorders (EDs) are increasingly frequent. Their pathophysiology involves disturbance of peptide signaling and the microbiota–gut–brain axis. This study analyzed peptides and corresponding immunoglobulin (Ig) concentrations in groups of ED. In 120 patients with restrictive (R), bulimic (B), and compulsive (C) ED, the plasma concentrations of leptin, glucagon-like peptide-1 (GLP-1), peptide YY (PYY), and insulin were analyzed by Milliplex and those of acyl ghrelin (AG), des-acyl ghrelin (DAG), and α-melanocyte-stimulating hormone (α-MSH) by ELISA kits. Immunoglobulin G (in response to an antigen) concentrations were analyzed by ELISA, and their affinity for the respective peptide was measured by surface plasmon resonance. The concentrations of leptin, insulin, GLP-1, and PYY were higher in C patients than in R patients. On the contrary, α-MSH, DAG, and AG concentrations were higher in R than in C patients. After adjustment for body mass index (BMI), differences among peptide concentrations were no longer different. No difference in the concentrations of the IgG was found, but the IgG concentrations were correlated with each other. Although differences of peptide concentrations exist among ED subtypes, they may be due to differences in BMI. Changes in the concentration and/or affinity of several anti-peptide IgG may contribute to the physiopathology of ED or may be related to fat mass.

The role of appetite-related hormones, adaptive thermogenesis, perceived hunger and stress in long-term weight-loss maintenance: a mixed-methods study.

Weight-loss maintenance is challenging, and few succeed in the long term. This study aimed to explain how appetite-related hormones, adaptive thermogenesis, perceived hunger and stress influence weight-loss maintenance. Fifteen adult women (age, 46.3 ± 9.5 years; BMI, 39.4 ± 4.3 kg/m2) participated in a 24-month intervention, which included 3-5 months total diet replacement (825-853 kcal/d). Body weight and composition (Magnetic Resonance Imaging), resting metabolic rate (indirect calorimetry), and fasting plasma concentration of leptin, ghrelin, glucagon-like peptide-1 (GLP-1), peptide YY (PYY), and growth differentiation factor 15 (GDF-15) were measured at baseline and after weight loss, around 6 months. Perceptions relating to weight-loss maintenance were explored using qualitative interviews. Mean (SD) changes in body weight (-13.8 ± 6.3 kg) and total adipose tissue (-11.5 ± 4.9 kg) were significant (P < 0.001). Weight loss was associated with a significant reduction in resting metabolic rate (-291 ± 226 kcal/day, P < 0.001) and adaptive thermogenesis (-150 ± 162 kcal/day, P = 0.003), reduction in leptin (P < 0.001) and GLP-1 (P = 0.015), an increase in ghrelin (P < 0.001), and no changes in PYY and GDF-15. Weight regain between 6 and 24 months (6.1 ± 6.3 kg, P < 0.05) was negatively correlated with GLP-1 at baseline (r = −0.7, P = 0.003) and after weight loss (r = -0.7, P = 0.005). Participants did not report increased hunger after weight loss, and stress-related/emotional eating was perceived as the main reason for regain. Weight regain is more likely with lower fasting GLP-1 at baseline and following weight loss, but psychological aspects of eating behaviour appear as important in attenuating weight-loss maintenance.

Appetite-regulating hormones and anthropometric indicators of infants according to the type of feeding.

It has been accepted that satiety‐ and appetite‐stimulating hormones play a role in the regulation of food intake and body composition during and after the lactation stage. Therefore, the purpose was to demonstrate that serum appetite‐regulating hormones in infants differ according to anthropometric indicators and type of feeding. In a nonrandom cohort study, 169 mother–newborn dyads whose pregnancy and birth were attended at the Hospital Civil de Guadalajara were enrolled. According to the type of feeding, infants were classified as full breastfeeding (FBF), partial breastfeeding (PBF), and infants receiving human milk substitutes (HMS). Serum concentrations of ghrelin (pg/ml), leptin (ng/ml), peptide YY (pg/ml), and glucagon‐like peptide‐1 (GLP‐1) (pM) were measured. Anthropometric measurements including weight, length, cephalic, arm circumference, tricipital, and subscapular skinfolds were obtained. Weight/age, weight/height, height/age, and BMI Z‐score indexes were estimated. We performed one‐way ANOVA, unpaired Student's t test, post hoc Tukey test, and Pearson correlation tests. The ANOVA comparison of the three feeding types showed significant differences in most anthropometric indicators (z‐scores), especially between infants receiving FBF versus HMS and particularly on indicators of adiposity; no differences were observed in length and cephalic circumference z‐scores at 8th and 16th weeks. Further, significant correlations were found between most of the adiposity indicators with ghrelin, leptin, and GLP‐1, especially in infants who received FBF. There were differences in anthropometric and body composition parameters among infants receiving FBF, PBF, and HMS. There were significant correlations between body composition indicators with ghrelin, leptin, and GLP‐1 mainly in infants receiving FBF.

Almond consumption improves satiety and ectopic fat content relative to a high-carbohydrate food: A pilot RCT in minority adults

AbstractNut consumers have lower body weight and are at lower cardiovascular disease risk than non-consumers. Interestingly, minority adults, who have the highest prevalence of obesity and are at disproportionate risk of cardiovascular disease, have low nut intakes. The goal of this study was to test whether consumption of almonds, compared to low-fat/high-carbohydrate cereal bars (LF-HC), as a supplement for 24 wk, would improve appetite regulation and body composition in Blacks and Hispanics. Twenty-nine adults, BMI &gt; 25 kg/m2, age 30–65 y, were recruited and randomized to consume either almonds or LF-HC providing 17.5% of their estimated energy requirements as part of their regular diet. A total of 17 adults completed the study, 9 men and 8 women; 7 of whom were randomized to almond consumption (4 men, 3 women), and 10 to LF-HC consumption (5 men, 5 women). Outcome variables included appetite-regulating hormones and inflammatory markers, which were measured from fasting blood samples taken at baseline, week 12, and endpoint. Body composition was measured by magnetic resonance imaging at baseline and endpoint. Data were analyzed using linear mixed model with treatment, time, and their interaction as predictor variables; age, race, sex, and baseline BMI as covariates; and participant ID as a random effect variable. Peptide YY concentrations were higher in the almond group compared to LF-HC (time x treatment interaction at 12 wk, P &lt; 0.001; 24 wk, P = 0.13). Glucagon-like peptide 1 concentrations were higher in the almond group compared to LF-HC (time x treatment interaction at 12 wk, P = 0.10; 24 wk, P = 0.015). Ghrelin levels decreased in LF-HC compared to the almond group at 12 wk but not 24 wk (time x treatment interaction at 12 wk, P = 0.017; 24 wk, P = 0.23). There was a slight trend for a time x treatment interaction on body weight (P = 0.14; change in almond = 0.6 ± 1.8 kg; LF-HC = 1.9 ± 2.7 kg). There was a time x treatment interaction on intermuscular adipose tissue (P = 0.013; change in almond = -0.10 ± 0.14 cm3; LF-HC = 0.04 ± 0.07 cm3). None of the measured inflammatory markers (C reactive protein, interleukin-6, and tumor necrosis factor) were affected by the dietary interventions. Despite the lack of profound body composition changes, daily almond intake for 24 wk, within the usual diet, ameliorated satiety and ectopic fat deposition, suggesting a potential role of nut consumption in the context of a weight reduction program in minority adults. Our data support further exploration of the health effects of nut consumption in this population.

Appetite and physiological responses to medium-chain triglycerides (MCT) and conjugated linoleic acid (CLA) in lean vs overweight/obese participants

AbstractMedium-chain triglycerides (MCT) are lipids which have been shown to yield appetite-suppressing properties compared to long-chain triglycerides (LCT), which are more commonly found in the diet. Conjugated linoleic acid (CLA) has also been shown to increase satiety and decrease subsequent energy intake, although CLA has received much less attention to date. The mechanisms behind the appetite-suppressing properties are yet to be fully elucidated. Furthermore, no study has directly compared these effects or mechanisms in overweight/obese individuals to a group of healthy-weight weight controls.Fifteen healthy-weight (BMI: 22.7 ± 1.9 kg/m2) and fourteen overweight/obese (BMI: 30.9 ± 3.9 kg/m2) individuals participated in a randomised single-blind cross-over study. Overnight fasted participants were fed smoothie breakfasts containing either 23.06 g vegetable oil (LCT), 25.0 g MCT oil (MCT), or 6.25 g CLA and 16.8 g vegetable oil (CLA) on separate test days. Subjective appetite ratings, peptide YY (PYY), total ghrelin, β-hydroxybutyrate, and gastric emptying (GE) were measured throughout each trial. Energy intake in the laboratory was measured at a buffet meal 3-h after the smoothie breakfast and for the following ~36-h in their free-living environment via food records.Energy intake and subjective appetite ratings were not affected by weight status, so results are presented as a whole. MCT reduced energy intake compared to LCT over the trial day and whole 48-h period, but not at the ad libitum lunch. There was no difference between CLA and LCT at any time point. There were no differences in postprandial subjective appetite ratings between trials. PYY concentrations were not affected by weight status (P = 0.170), and did not differ between trials (P = 0.743) and total ghrelin was also not affected by weight status (P = 0.306), and concentrations were similar between trials (P = 0.188). β-hydroxybutyrate concentrations were higher in the overweight/obese group compared to the lean group (P = 0.009), and MCT led to increased concentrations compared to both LCT (P = 0.005) and CLA (P &lt; 0.001). MCT delayed GE half-time (P &lt; 0.001), lag-phase (P &lt; 0.001), latency phase (P = 0.01), and ascension time (P &lt; 0.001) compared to LCT, with no differences in GE between LCT and CLA (all P &gt; 0.05).MCT consumption reduces intake over the subsequent 48-h, whereas CLA has no effect compared to LCT. This does not appear to be related to PYY or total ghrelin, but may be mediated by β-hydroxybutyrate or via a delay of gastric emptying.

Serum Concentrations of Cholecystokinin, Peptide YY, Ghrelin and High Sensitive C-Reactive Protein in Association with Metabolic Syndrome Ingredients in Obese Individuals

Metabolic syndrome (MetS) is a metabolic condition with high prevalence worldwide. This study aims to examine the relationship between serum concentrations of gastrointestinal hormones such as cholecystokinin (CCK), ghrelin, peptide YY (PYY), and high sensitive C-reactive protein (hs-CRP) and the ingredients of MetS in obese population. This case-control study included 40 obese subjects (20 with MetS and 20 BMI and age-matched control individuals). The age range of the participants was 20-50 years and the participants' anthropometric characteristics were measured. Serum lipids and the concentrations of oxidized low density lipoprotein (Ox-LDL), insulin, hs-CRP, CCK, PYY, and ghrelin were assessed with commercial ELISA kits. Serum levels of hs-CRP, total cholesterol (TC) and triglycerides (TG) in patients with MetS were significantly higher while CCK and insulin concentrations were higher in obese non- MetS group (P <0.05). PYY had a negative association with waist circumference (WC) and high density lipoprotein cholesterol (HDL-C) and ghrelin had a positive association with systolic blood pressure (SBP) and TC in obese control group (P < 0.05). In obese patients with MetS, hs-CRP had a strong positive association with TG. The current study revealed the possible role of hs-CRP and several GI- hormones in the pathogenesis of obesity-associated diseases and MetS. Additional works are needed to elucidate the possible underlying mechanisms and clarify several controversies in this issue.

Dairy products influence gut hormone secretion and appetite differently: A randomized controlled crossover trial

Little is known about how dairy products with different nutrient contents and food matrices affect appetite sensation and gut hormone secretion. The objective of this study was to investigate how appetite sensation and gut hormone secretion in healthy adults are affected by meals with the same amount of fat but from different dairy products. Forty-seven healthy adults (70% women) were recruited to a randomized controlled crossover study with 4 dairy meals consisting of butter, cheese, whipped cream, or sour cream, corresponding to 45 g (approximately 60 energy percent) of fat. Plasma samples were collected for analysis of cholecystokinin (CCK), pancreatic polypeptide (PP), peptide YY (PYY), and ghrelin concentrations at 0, 2, 4, and 6 h after the meals and analyzed as the incremental area under the curve (iAUC0-6h) in a mixed model. Hunger, satiety, and appetite sensations were measured with a visual analog scale (VAS) immediately after finishing the meals and at 4 and 6 h postprandially. Intake of cheese induced a higher level of plasma PP-iAUC0-6h compared with butter or whipped cream, and a higher level of plasma CCK-iAUC0-6h compared with whipped cream. Intake of whipped cream increased VAS appetite at 4 h compared with cheese or sour cream, and at 6 h compared with cheese or butter. No significant meal effect was found for hunger, satiety, plasma PYY, or plasma ghrelin concentration. Intake of cheese increased postprandial plasma PP and CCK concentrations and decreased appetite compared with whipped cream but not with sour cream. These findings encourage further investigations of how different dairy products affect gut hormone secretion and appetite sensation.

Short-term effects of Vertical sleeve gastrectomy and Roux-en-Y gastric bypass on glucose homeostasis

The objective of this study was to compare the biochemical changes related to glucose tolerance and lipid metabolism in non-diabetic patients shortly after vertical sleeve gastrectomy (SG) or Roux-en-Y gastric bypass (RYGB). Non-diabetic women and men with morbid obesity were studied the day before and six days after SG (N = 15) or RYGB (N = 16). Patients completed an oral glucose tolerance test (OGTT; 75 g glucose) at both visits. SG and RYGB similarly improved fasting glucose homeostasis six days after surgery, with reduced glucose and insulin concentrations. The OGTT revealed differences between the two surgery groups that were not evident from the fasting serum concentrations. Postprandial (120 min) glucose and insulin concentrations were lower after RYGB but not after SG, whereas concentrations of glucagon-like peptide-1, peptide YY, glucagon and non-esterified fatty acids were elevated after both SG and RYGB. Fasting triacylglycerol concentration did not change after surgery, but concentrations of high density lipoprotein and low density lipoprotein cholesterols were reduced in both surgery groups, with no differences between the groups. To conclude, RYGB induced a more pronounced improvement in postprandial glucose homeostasis relative to SG, possibly due to improved insulin sensitivity rather than augmented insulin concentration.

Effects of copper hydroxychloride and choice white grease on growth performance and blood characteristics of weanling pigs kept at normal ambient temperature or under heat stress

An experiment was conducted to test the hypothesis that copper (Cu) hydroxychloride improves growth performance and blood characteristics, and reduces diarrhea incidence in weanling pigs without or with exposure to heat stress. One hundred sixty pigs (6.14 ± 0.90 kg) were allotted to a 2 × 2 factorial arrangement with 2 levels of choice white grease (CWG; 0 or 50 g/kg) and 2 levels of Cu from Cu hydroxychloride (0 or 100 mg/kg). There were 5 pigs per pen and 8 pen replicates per diet. Fecal scores were visually assessed using a score from 1 to 5 (1 = normal feces to 5 = watery feces). On day 40 until the end of the experiment, ambient temperature was increased from 24 °C to 32 °C to create a mild heat stress. On day 14, day 28, day 40, and on day 44, blood samples were collected from 1 pig per pen and tumor necrosis factor-α (TNF-α), peptide YY, immunoglobulin G, blood urea nitrogen, total protein, and albumin were analyzed. Results indicated that there were no interactions between CWG and Cu hydroxychloride for overall growth performance. Greater (P < 0.05) gain:feed was observed from day 29 to 40 and from day 41 to 44 for pigs fed diets with 50 g/kg CWG compared with pigs fed diets without supplemental fat. Average daily gain was greater (P < 0.05) from day 15 to 28 and also during exposure to heat stress, and fecal scores were reduced over the entire period (P < 0.05) for pigs fed diets with Cu hydroxychloride compared with pigs fed diets without Cu hydroxychloride. There was also an increase (P < 0.05) in concentration of peptide YY and a reduction (P < 0.05) in TNF-α concentration on day 14 for pigs fed Cu hydroxychloride diets compared with pigs fed diets without Cu hydroxychloride. This may be attributed to the effect of Cu in enhancing the expression of hypothalamic appetite regulators and its bacteriostatic property in reducing inflammation caused by pathogens. In conclusion, supplementation of Cu hydroxychloride to diets fed to weanling pigs without or with addition of CWG reduces diarrhea incidence and improves growth performance and some blood characteristics.

Effects of dietary taurine supplementation on growth performance, jejunal morphology, appetite-related hormones, and genes expression in broilers subjected to chronic heat stress

This study was aimed to elucidate effects of taurine supplementation on growth performance, jejunal histology, and appetite-related genes expressions of broilers under heat stress. A total of 144 broilers on 28 d were allocated to three groups with 6 cages each group, 8 broilers per cage. The experiment period is from 28 to 42 d of age. In normal control (NC) group, chickens were held at 22°C ambient temperature (thermoneutral) and fed a basal diet. In the heat stress (HS) group, chickens were raised to constant HS at 32°C and received a basal diet. In the HS+ taurine group, chickens were fed a basal diet with 5g/kg taurine supplementation. The results showed that HS group had lower average daily feed intake, average daily gain, higher feed/gain ratio compared with the NC group (P < 0.05), while taurine addition did not ameliorate the lowered growth performance. Cloacal temperatures and respiration rates in the HS and heat taurine group were higher (P < 0.05) than in the NC group. Heat stress treatment elevated (P < 0.05) the concentrations of ghrelin and cholecystokinin (CCK) in serum and intestine, together with peptide YY and somatostatin (SS) in the intestine after 7 or 14 d of heat exposure. In addition, HS damaged the jejunal morphology by shortening villus height and deepening crypt depth (P < 0.05), upregulated (P < 0.05) the mRNA expression of taste receptor type 1 member 1 (T1R1), taste receptor type 1 member 3 (T1R3), CCK and ghrelin in the intestine. Taurine supplementation significantly mitigated the impairment of jejunal morphology, decreased the concentrations of serum ghrelin, increased the concentrations of somatostatin and peptide YY in the duodenum, elevated the mRNA expression levels of CCK in the jejunum compared with the HS group. In conclusion, taurine exerted no positive effects on the growth performance, while mitigated the impairment of jejunal morphology, increased some anorexic hormones secretion and mRNA expression of appetite-related genes in the intestine of broilers subjected to HS.

True Interindividual Variability Exists in Postprandial Appetite Responses in Healthy Men But Is Not Moderated by the FTO Genotype

ABSTRACTBackgroundAfter meal ingestion, a series of coordinated hormone responses occur concomitantly with changes in perceived appetite. It is not known whether interindividual variability in appetite exists in response to a meal.ObjectivesThe aim of this study was to 1) assess the reproducibility of appetite responses to a meal; 2) quantify individual differences in responses; and 3) explore any moderating influence of the fat mass and obesity associated (FTO) gene.MethodsUsing a replicated crossover design, 18 healthy men (mean ± SD age: 28.5 ± 9.8 y; BMI: 27.0 ± 5.0 kg/m2) recruited according to FTO genotype (9 AA, 9 TT) completed 2 identical control and 2 identical standardized meal conditions (5025 kJ) in randomized sequences. Perceived appetite and plasma acylated ghrelin, total peptide YY (PYY), insulin, and glucose concentrations were measured before and after interventions as primary outcomes. Interindividual differences were explored using Pearson's product-moment correlations between the first and second replicates of the control-adjusted meal response. Within-participant covariate-adjusted linear mixed models were used to quantify participant-by-condition and genotype-by-condition interactions.ResultsThe meal suppressed acylated ghrelin and appetite perceptions [standardized effect size (ES): 0.18–4.26] and elevated total PYY, insulin, and glucose (ES: 1.96–21.60). For all variables, SD of change scores was greater in the meal than in the control conditions. Moderate-to-large positive correlations were observed between the 2 replicates of control-adjusted meal responses for all variables (r = 0.44–0.86, P ≤ 0.070). Participant-by-condition interactions were present for all variables (P ≤ 0.056). FTO genotype-by-condition interactions were nonsignificant (P ≥ 0.19) and treatment effect differences between genotype groups were small (ES ≤ 0.27) for all appetite parameters.ConclusionsReproducibility of postprandial appetite responses is generally good. True interindividual variability is present beyond any random within-subject variation in healthy men but we detected no moderation by the FTO genotype. These findings highlight the importance of exploring individual differences in appetite for the prevention and treatment of obesity. This trial was registered at clinicaltrials.gov as NCT03771690.

Pectin reduces environmental pollutant-induced obesity in mice through regulating gut microbiota: A case study of p,p′-DDE

BackgroundThe prevalence of obesity has raised global concerns. Environmental pollutants are one of the main causes of obesity. Many studies have demonstrated that dietary fiber could reduce obesity induced by high-fat diets, but whether environmental pollutant-induced obesity can be reversed is still unknown. ObjectivesThis study aimed to investigate the effects of pectin on obesity induced by a typical environmental pollutant p,p'-dichlorodiphenyldichloroethylene (p,p′-DDE) and explore the underlying mechanism by which pectin reversed p,p′-DDE-induced obesity. Methodsp,p′-DDE was used to induce obesity in C57BL/6J mice and pectin was supplied during and after cessation of p,p'-DDE exposure. Body and fat weight gain, plasma lipid profile and insulin resistance of mice were assessed. Gut microbiota composition and the levels of short-chain fatty acids (SCFAs) as well as the receptor proteins and hormones in the SCFAs-related signaling pathway were analyzed. Moreover, p,p′-DDE levels in various tissues of mice were detected. ResultsPectin supplementation reversed body and fat weight gain, dyslipidemia, hyperglycemia and insulin resistance in p,p′-DDE-exposed mice. Furthermore, pectin apparently altered the p,p′-DDE-induced microbial composition and then promoted the levels of SCFAs in colonic feces as well as the expression of G-protein coupled receptors and the concentration of hormone peptide YY (PYY) and glucagon like peptide-1 (GLP-1). Pectin treatment also significantly reduced p,p′-DDE accumulation in mice tissues during p,p′-DDE exposure but did not change p,p′-DDE metabolism after termination of p,p′-DDE exposure. ConclusionsPectin had a good effect on reducing p,p′-DDE-induced obesity through regulating gut microbiota and provided a potential strategy for the treatment of environmental pollutant-caused health problems.

1974-P: Identification of a Dual-Action Small Molecule with Potent Antidiabetic Activity

Type 2 diabetes (T2D) is a result of insulin resistance and pancreatic β-cell dysfunction. Therefore, identifying agents that simultaneously reverse these two defects could be a novel strategy leading to more effective prevention and treatment of T2D. Recently, we generated a small molecule elenolic acid moiety (EA). Here, we report that oral administration of EA normalized glycemia, glucose tolerance, insulin sensitivity, and hepatic glucose production in high-fat diet (HFD)-induced obese mice. These metabolic and antihyperglycemic effects of EA treatment were associated with increased circulating GLP-1 and peptide YY concentrations, but reduced blood insulin, leptin, and lipid levels. In addition, EA slowed gastric emptying and reduced food intake, body weight, and fat mass in HFD-fed obese mice. In vitro, EA directly induces glucagon-like peptide-1 (GLP-1) release from intestinal L-cells via a Gαq/phospholipase C-mediated mechanism. It also suppresses glucose production from HepG2 cells and stimulates glucose uptake in primary human skeletal muscle cells. These data suggest that EA may be a novel agent for developing drug to treat T2D. Disclosure Y. Wang: None. J. Luo: None. H.A. Alkhalidy: None. B. Xu: None. D. Liu: None. Funding National Institutes of Health (1R01AT007077, 1R01AT007566)

Fluid Restriction Decreases Solid Food Consumption Post-Exercise.

Dehydration in rodents induces anorexia. In humans however, the role of dehydration in energy intake is controversial. This study investigated the effect of extreme fluid restriction on acute energy intake during and after exercise-induced dehydration. Eight physically active participants performed two exercise sessions to induce dehydration. After the exercise, the men were allowed to either rehydrate for 2 h or were maintained in a hypohydrated state, in a randomized manner. After 2 h, they were given cereal bars ad libitum for 1 h. Blood and saliva samples of the participants were collected before the exercise session, after the exercise session, after rehydration, and after the meal. Post-exercise energy intake differed between hypohydrated (1430 ± 210 kcal) and rehydrated (2190 ± 780 kcal) trials (p = 0.01). For the concentrations of ghrelin and leptin, there were no significant effects of time (p = 0.94, p = 0.21), between trials (p = 0.09, p = 0.99), or due to a trial–time interaction (p = 0.64, p = 0.68), respectively. The concentrations of peptide YY (PYY) were not different between trials (p = 0.94) but there was a significant effect of time (p = 0.0001) and a trial–time interaction (p = 0.01), with higher levels in the rehydration trial after eating in response to a higher energy intake. For saliva production, there was a significant effect of time (p = 0.02) and a trial–time interaction (p = 0.04), but no between-trial effect (p = 0.08). In conclusion, extreme fluid restriction decreased acute food intake after exercise, which may be explained by a lower flow of saliva.

Physiological Predictors of Weight Regain at 1-Year Follow-Up in Weight-Reduced Adults with Obesity.

ObjectiveThis study aimed to assess whether changes in resting metabolic rate (RMR), exercise‐induced energy expenditure (EIEE), and appetite following weight loss (WL) are associated with weight regain at 1 year.MethodsThirty‐six adults with obesity underwent 8 weeks of a very‐low‐energy diet, followed by 4 weeks of refeeding and a 1‐year maintenance program. RMR, EIEE, appetite ratings, and active ghrelin, peptide YY, glucagon‐like peptide‐1, cholecystokinin, and insulin concentrations were measured at baseline, week 13, and 1 year.ResultsA 17% WL (−20 ± 5 kg [mean ± SD]; range: −11.7 to −32.2 kg; P < 0.001) was achieved at week 13. After 1 year, weight regain was 2.5 ± 9.0 kg (not significant), ranging from −18.2 to 22.5 kg. Both fat mass and fat‐free mass were reduced at week 13 (−17.9 ± 4.8 and −2.9 ± 2.7 kg, respectively; P < 0.001), while only loss of fat mass was sustained at 1 year. WL was associated with reduced RMR, EIEE, and fasting/postprandial insulin (all P < 0.001), as well as increased fasting hunger (P < 0.01) and fasting/postprandial active ghrelin (P < 0.001). There were no significant correlations between changes in RMR, EIEE, or appetite with WL and weight regain at 1 year.ConclusionsNo clear evidence emerged that changes in RMR, EIEE, or appetite following WL can predict weight regain at 1 year, but larger studies are needed to confirm these results.