Hunger Responses Research Articles

Genetic associations with consumption of palatable foods in the absence of hunger in response to food cues in children.

The objective of this study is to evaluate obesity-related genetic factors in relation to excess consumption and assess if food cues modify associations. Children (9-12 years) completed a randomized crossover experiment. During two visits, children ate a preload and then snacks ad libitum while watching television, embedded with food or non-food advertisements to assess eating in the absence of hunger (EAH). Primary exposures were obesity-associated genotypes, FTO rs9939609 and MC4R rs571312, and a paediatric-specific polygenic risk score (PRS). Outcomes included consumption of all snacks (total EAH) and gummy candy only (gummy candy EAH). Linear mixed-effects models tested whether genetic exposures related to EAH outcomes. We tested for effect modification by food cues using multiplicative interaction terms. Among 177 children, each FTO risk allele was associated with a 30% increase in gummy candy EAH (p = 0.025) in adjusted models. Food cue exposure exacerbated associations between the FTO variant with gummy candy EAH (p = 0.046). No statistically significant associations were found between MC4R and EAH. The results suggest children with the FTO rs9939609 risk allele may be predisposed to excess consumption of candy and that this association may be exacerbated by food cues.

GLYCATION-LOWERING COMBO EXTENDS LIFESPAN, IMPROVES INSULIN, REDUCES CALORIC INTAKE

Abstract Non-enzymatic reactions in glycolysis lead to the accumulation of methylglyoxal (MGO), a reactive precursor to advanced glycation end-products (AGEs), which has been suggested to drive obesity- and aging-associated pathologies. We observe that a combination of nicotinamide, lipoic acid, thiamine, pyridoxamine and piperine, which were selected to lower glycation (Gly-Low), reduce toxic glycolytic byproducts, MGO and MGO-derived AGE, MG-H1. Administration of Gly-Low reduced food consumption and body weight, improving insulin sensitivity and survival in both leptin receptor deficient (Lepr db) and wildtype C57 control mouse models. Unlike calorie restriction, Gly-Low inhibited ghrelin-mediated hunger responses and upregulated Tor pathway signaling in the hypothalamus. Gly-Low also extended lifespan when administered as a late life intervention, suggesting its potential benefits in ameliorating age-associated decline by inducing voluntary calorie restriction and reducing glycation.

Impact of a Web-Based Nutrition Intervention on Eating Behaviors and Body Size Preoccupations among Adolescents.

We aimed to evaluate the impact of a web-based school nutrition intervention on eating behavior traits, body weight concern, body size perception and body size dissatisfaction in adolescents. Ten classes of secondary students in Canada (13.6 ± 0.8 years) were randomized into an intervention (n = 162 students) or control group (n = 75 students). Adolescents in the intervention, conducted between 2011 and 2013, participated in an online nutrition challenge to increase their consumption of vegetables, fruits and dairy products using a web-based platform over six weeks. Measurements were taken at baseline (PRE) and post-intervention (POST). No significant negative changes were observed between the intervention and control groups for eating behavior traits, body weight concern, body size perception and dissatisfaction. However, results suggest a trend for a positive effect of the intervention on susceptibility to hunger in boys (group × time interaction, p = 0.10). Specifically, boys experienced a reduction in their susceptibility to hunger in response to the intervention (PRE: 6.1 ± 3.8, POST: 4.8 ± 3.7, p = 0.009). An intervention aimed at improving the eating habits of adolescents did not negatively influence body size preoccupations. In response to the intervention, boys tended to show a lower susceptibility to hunger, which might help them to prevent overeating and adopt healthy eating habits.

Does flaxseed and chia use affect postprandial glucose, insulin and subjective saturation response in healthy individuals?

Background/Aim: In recent years, there has been an increase in the prevalence of obesity and its complications, along with a growing awareness of healthy nutrition. As a result, consumers are seeking to incorporate more functional foods into their diets. Chia and flax seeds have gained popularity due to their soluble fiber and antioxidant capacity. This study aims to compare the effects of consuming cakes made with the addition of chia and flax seeds on blood glucose and insulin levels, as well as evaluate their impact on post-consumption satiety response in individuals. Methods: This randomized, double-blind, self-controlled experimental study involved 12 volunteers (19–64 years old) who were free from acute or chronic diseases. The participants had a body mass index (BMI) value between 18.5 and 24.9 kg/m2 and a Beck Depression Inventory score of 8 or below. The study investigated the effects of standard and test cakes containing 50 g of digestible carbohydrates, including chia-added cake, flaxseed-added cake, and chia+flaxseed-added cake. Postprandial blood sugar, insulin, and subjective satiety responses were assessed. A standard nutrition program (diet: 60% carbohydrates, 20% protein, 30% fat) was implemented at least one week before the study, and participants were asked to maintain 24-h food consumption records the day before the test days. Throughout the study period, individuals were instructed to avoid caffeine, medication, nutritional supplements, and heavy physical activity. Cake consumption sessions were conducted at the research center, with participants visiting four times in total, with at least 1-week intervals. Fasting for 10–12 h prior to each visit, saturation responses were measured using a visual analog scale at 0, 15, 30, 60, 90, 120, and 180 min. Blood samples were also collected to assess blood glucose and insulin levels. Results: The study revealed that cakes containing chia and flaxseeds, compared to the standard cake, as well as flaxseed-added cake compared to chia-added cake, resulted in higher plasma glucose under-curve values and saturation responses and lower hunger responses (P=0.038, P=0.016, P=0.004, respectively). Conclusion: The findings indicate that both chia and flax seeds impact glycemic control and the sensation of satiety, with flaxseed exhibiting greater effectiveness than chia.

1536-P: Effects of Sucralose vs. Sucrose on Hypothalamic Blood Flow, Glucose Signaling, and Appetite

Sucralose is a non-nutritive sweetener (NNS) commonly consumed to provide sweet taste without calories. Yet, some studies suggest NNS stimulate appetite, potentially by altering post-ingestive metabolic signals that communicate with the hypothalamus to reduce hunger. We tested the hypothesis that sucralose vs sucrose would elicit different metabolic, hypothalamic blood flow (BF) and appetite responses, and that post-ingestive increases in metabolic signals would be associated with reductions in hypothalamic BF and hunger. In a randomized cross-over trial, hypothalamic BF (measured by perfusion MRI), appetite ratings, and glucose/hormone responses were obtained before, 15 and 30 min after ingestion of drinks containing sucrose (75g) or sucralose (sweetness matched). Paired t-tests were used to compare sucralose vs sucrose on metabolic responses, hypothalamic BF, and appetite. Linear regression was used to examine associations between peripheral glucose, insulin, GLP-1 and hypothalamic BF and hunger. 76 adults (43F; 23.3±3.9 yrs; BMI 27.2±5) completed the study. Subjects reported increased hunger at 15 (p<.04) and 30min (p<.003) after sucralose vs sucrose. Peripheral glucose, insulin, and GLP-1 were lower after sucralose vs sucrose (all p<.0001). Glycemic response (whole hypothalamus (β=-.002, p=.05), medial subfield (β=−.005, p<.006)), but not insulin or GLP-1, was associated with the hypothalamic response to sucrose at 30 min, controlling for age, sex, BMI. These associations were not observed after sucralose (β=.008 p=.2). The medial hypothalamic response predicted hunger response after both drinks (β=1.79, p<.02). Sucralose vs sucrose elicited disparate metabolic, hypothalamic, and hunger responses. Sucrose-induced increases in glycemia were associated with reductions in medial hypothalamic BF, which was linked to reduced hunger. Compared to sucrose, post-ingestive signaling responses were altered after sucralose, which may affect appetite. Disclosure S.P.Chakravartti: None. K.A.Page: None. S.Kullmann: None. R.Veit: None. A.G.Yunker: None. B.C.Angelo: None. K.Jann: None. S.H.Luo: None. A.Xiang: None. J.R.Monterosso: None. Funding National Institute of Diabetes and Digestive and Kidney Diseases (R01DK102794)

Timing of daily calorie loading affects appetite and hunger responses without changes in energy metabolism in healthy subjects with obesity

SummaryMorning loaded calorie intake in humans has been advocated as a dietary strategy to improve weight loss. This is also supported by animal studies suggesting time of eating can prevent weight gain. However, the underlying mechanisms through which timing of eating could promote weight loss in humans are unclear. In a randomized crossover trial (NCT03305237), 30 subjects with obesity/overweight underwent two 4-week calorie-restricted but isoenergetic weight loss diets, with morning loaded or evening loaded calories (45%:35%:20% versus 20%:35%:45% calories at breakfast, lunch, and dinner, respectively). We demonstrate no differences in total daily energy expenditure or resting metabolic rate related to the timing of calorie distribution, and no difference in weight loss. Participants consuming the morning loaded diet reported significantly lower hunger. Thus, morning loaded intake (big breakfast) may assist with compliance to weight loss regime through a greater suppression of appetite.

Intermittent fasting two days versus one day per week, matched for total energy intake and expenditure, increases weight loss in overweight/obese men and women

BackgroundIntermittent fasting (IF), consisting of either a one-day (IF1) or two consecutive days (IF2) per week, is commonly used for optimal body weight loss. Our laboratory has previously shown an IF1 diet combined with 6d/week of protein pacing (P; 4–5 meals/day evenly spaced, ~ 30% protein/day) significantly enhances weight loss, body composition, and cardiometabolic health in obese men and women. Whether an IF1-P or IF2-P, matched for weekly energy intake (EI) and expenditure (EE), is superior for weight loss, body composition, and cardiometabolic health is unknown.MethodsThis randomized control study directly compared an IF1-P (n = 10) versus an IF2-P (n = 10) diet on weight loss and body composition, cardiovascular (blood pressure and lipids), hormone, and hunger responses in 20 overweight men and women during a 4-week weight loss period. Participants received weekly dietary counseling and monitoring of compliance from a registered dietitian. All outcome variables were assessed pre (week 0) and post (week 5).ResultsBoth groups significantly reduced body weight, waist circumference, percent body fat, fat mass, hunger, blood pressure, lipids, glucose, and increased percent fat-free mass (p < 0.05). However, IF2-P resulted in significantly greater reductions in body weight (-29%) and waist circumference (-38%) compared to IF1-P (p < 0.05), and showed a strong tendency for greater reductions in fat mass, glucose, and hunger levels (p < 0.10) despite similar weekly total EI (IF1-P, 9058 ± 692 vs. IF2-P, 8389 ± 438 kcals/week; p = 0.90), EE (~ 300 kcals/day; p = 0.79), and hormone responses (p > 0.10).ConclusionsThese findings support short-term IF1-P and IF2-P to optimize weight loss and improve body composition, cardiometabolic health, and hunger management, with IF2-P providing enhanced benefits in overweight women and men.Trial registrationThis trial was registered March 03, 2020 at www.clinicaltrials.gov as NCT04327141.

The Relationship of Hedonic Hunger With Depression and Physical Activity in Students of Faculty of Health Sciences

The study was conducted to examine the hedonic hunger, physical activity, and depression status of healthy university students and to reveal the relationship between these parameters. A total of 174 healthy university students were included in the study. Hedonic hunger responses were similar at different physical activity levels. When the relationship between individuals' hedonic hunger responses and intensity of depression was examined, it was found that there was a weak positive correlation between them. Hedonic hunger can have negative effects on university students' depression status. Taking precautions to improve nutrition and physical activity in university students can be effective in preventing this problem.

Of Mice and Men: Impacts of Calorie Restriction on Metabolomics of the Cerebellum.

The main purpose of research in mice is to explore metabolic changes in animal models and then predict or propose potential translational benefits in humans. Although some researchers in the brain research field have mentioned that the mouse experiments results still lack the complex neuroanatomy of humans, caution is required to interpret the findings. In mice, we observed in article seventeenth of the series of the effects of graded levels of calorie restriction, metabolomic changes in the cerebellum indicated activation of hypothalamocerebellar connections driven by hunger responses. Therefore, the purpose of the current perspective is to set this latest paper into a wider context of the physiological, behavioral, and molecular changes seen in these mice and to compare and contrast them with previous human studies.

Influence of glycaemic index on subjective appetite responses in healthy adults

The glycaemic index (GI) of carbohydrate foods is a useful tool for predicting postprandial glucose and insulin responses(1). Results from human studies suggest an inverse relationship between GI of ingested food and postprandial appetite responses(2). However, evidence on the effects of GI on subjective and objective satiety responses is inconclusive(3). Therefore, the aim of this study was to assess the impact of GI on postprandial appetite response in humans. We conducted a randomised controlled crossover trial on 13 adults presenting with normoglycaemia, normal BMI and mean age of 28.7 ± 6.6 years. Participants were randomly allocated to consume a high GI meal (HGI) consisting of mashed potatoes, and low GI (LGI) meal of canned whole chickpeas, each providing 50 g total available carbohydrates, after an overnight fast. Postprandial subjective satiety and appetite responses were captured using visual analogue scale (VAS) in 3 domains: hunger, fullness, and prospective food intake. Plasma ghrelin values were also measured by immunoassay (intra-assay variations < 15%), in venous blood samples collected over 3 hours following breakfast intake. Postprandial total area under the curves (AUCs) were calculated by the trapezoidal method, and data were analysed using t-test with statistical significance set at p < 0.05. Data are presented as mean ± SD. There were great variations observed in individual responses after intake of both interventions in all outcomes illustrated above. Postprandial hunger responses were significantly lower after ingestion of LGI meal (91.2 ± 37.1 mm × h) in comparison to HGI meal (113.5 ± 26 mm × h) (p = 0.035); and postprandial fullness responses were significantly higher as demonstrated by AUC values over the 3 hour period following breakfast intake (107.3 ± 37.1 mm × h) and (80.2 ± 24.7 mm × h) (p = 0.012) respectively. However, there was no significant difference in prospective food intake following different GI meals (104.6 ± 41.9 mm × h) and (126.2 ± 26.3 mm × h), respectively. In addition, there were no differences observed in postprandial ghrelin response (p > 0.05). The results suggest that a low meal GI positively affects postprandial satiety response. However, the impact on appetite hormone ghrelin is unclear possibly due to high individual variances in hormonal responses.

Emotional traumatic experiences significantly contribute to identify a maltreated ecophenotype sub-group in eating disorders: Experimental evidence.

Eating disorders (EDs) are associated with a high prevalence of childhood maltreatment (CM). We aimed to experimentally assess if people with EDs and history of CM show altered biological, emotional and behavioural responses to the Trier Social Stress Test (TSST). According to Childhood Trauma Questionnaire cut-off scores, 29 participants (14 with anorexia nervosa [AN] and 15 with bulimia nervosa [BN]) were classified as maltreated (Mal) ED participants while 19 participants (11 with AN and eight with BN) without CM were identified as no maltreated (noMal) ED participants. Cortisol, anxiety and hunger responses to TSST and post-stress body dissatisfaction were measured. Mal ED people showed heightened emotional reactivity, lower levels of hunger and more severe post-stress body dissatisfaction in comparison with noMal ones. Higher cortisol production was observed in people with AN, regardless of CM history, and in those with BN and emotional CM. Emotional trauma was the main CM type contributing to the experimental differences observed in Mal ED people. This is the first study providing experimental and multi-level support to the maltreated ecophenoptype hypothesis in people with EDs. These findings may promote new insights into the biological bases of EDs and provide novel therapeutic implications.

The Effects of Graded Levels of Calorie Restriction: XVI. Metabolomic Changes in the Cerebellum Indicate Activation of Hypothalamocerebellar Connections Driven by Hunger Responses.

Calorie restriction (CR) remains the most robust intervention to extend life span and improve healthspan. Though the cerebellum is more commonly associated with motor control, it has strong links with the hypothalamus and is thought to be associated with nutritional regulation and adiposity. Using a global mass spectrometry-based metabolomics approach, we identified 756 metabolites that were significantly differentially expressed in the cerebellar region of the brain of C57BL/6J mice, fed graded levels of CR (10, 20, 30, and 40 CR) compared to mice fed ad libitum for 12 hours a day. Pathway enrichment indicated changes in the pathways of adenosine and guanine (which are precursors of DNA production), aromatic amino acids (tyrosine, phenylalanine, and tryptophan) and the sulfur-containing amino acid methionine. We also saw increases in the tricarboxylic acid cycle (TCA) cycle, electron donor, and dopamine and histamine pathways. In particular, changes in l-histidine and homocarnosine correlated positively with the level of CR and food anticipatory activity and negatively with insulin and body temperature. Several metabolic and pathway changes acted against changes seen in age-associated neurodegenerative disorders, including increases in the TCA cycle and reduced l-proline. Carnitine metabolites contributed to discrimination between CR groups, which corroborates previous work in the liver and plasma. These results indicate the conservation of certain aspects of metabolism across tissues with CR. Moreover, this is the first study to indicate CR alters the cerebellar metabolome, and does so in a graded fashion, after only a short period of restriction.

Does protein supplementation impact appetite and energy intake in older adults? A systematic review

AbstractProtein supplementation represents an attractive strategy to prevent skeletal muscle mass loss and function with aging. However, it could be counterproductive in older adults, due to adverse effects on appetite and energy intake (EI). Understanding the effects of protein supplementation on appetite and energy intake is therefore key when investigating the potential efficacy for use in improving health outcomes. This systematic review aimed to assess the literature investigating the effects of protein supplementation on energy intake, and/or appetite in healthy older adults.PubMed and The Cochrane Library, as well as MEDLINE, CINAHL, EBSCO, and Web of Science databases were searched up to 21 March 2019 for published studies and theses. The review was limited to randomized controlled trials and longitudinal studies in healthy adults over 60 years of age that reported effects of protein supplementation compared to control or pre-intervention on appetite and/or energy intake. The review was conducted according to PRISMA guidelines.Out of 5,429 articles screened, 90 full-texts were reviewed and twenty-six studies (11 acute, 15 longitudinal) included. Studies involved a total of 1439 participants (502 male, 881 females). Of the acute studies, 3 reported conditions in which appetite was suppressed, 5 studies reported no effect and one study reported a condition in which appetite ratings increased following a protein load versus control. Three studies reported conditions in which ad libitum test meal EI was suppressed following protein preload and 7 reported no difference. When examining total EI (accounting for protein supplement and test meal), 2 studies reported no difference and 8 reported conditions where total EI was increased with protein supplement compared to control. Longitudinal studies ranged from 2–26 weeks duration. Two studies reported effects on appetite, one showing hunger to be suppressed on higher (1.0g/kg/d) compared to lower protein diet, and another showing hunger in response to whey consumption increased, but fullness also increased.14 studies reported effects on EI, most commonly assessed by food diary, and all showed no effect of increased protein intake compared to control on daily EI.The systematic review indicates that while appetite may be suppressed under some conditions, the current literature supports protein supplementation in older adults, as it either has a positive effect or no effect on total EI in both short and longer-term studies. Therefore, protein supplementation may represent an effective solution to address protein deficiencies in older adults without compromising daily EI.

Genetic Variation and Mood Response to Exercise in the TIGER Study (OR08-08-19)

ObjectivesOur primary objective is to determine how mood response to exercise is influenced by genetic variation, controlling for exercise quantity and quality. MethodsThe Training Interventions and Genetics of Exercise Response (TIGER) Study is a prospective cohort study, in which sedentary subjects (18–35y, <30 min/wk for 30d prior to enrollment) participated in a 15-week program, exercising within a prescribed (65–85% maximum heart rate reserve) target heart rate zone for 3 d/wk. Before and after each exercise session, a subset of subjects (n = 247) completed a 10 cm visual analog scale (VAS: 0–100) for four mood states: fatigue, tension, depression, and hunger. Multiple linear regression was performed to examine the association between variation in DRD2, BDNF, and FTO genes and change in mood state following exercise, controlling for gender, exercise duration, and intensity. ResultsExercise was associated on average with reduced feelings of fatigue (−3.18 ± 16.37), tension (−3.85 ± 12.97), and depression (−5.12 ± 8.20), and increased feelings of hunger (6.06 ± 10.54). Carriers of the major allele (A) in rs1362570 for the FTO gene experienced greater reductions in tension following exercise (AA or AG: −5.19 ± 1.08 vs GG: −1.16 ± 1.24, P < 0.02, respectively). Homozygotes for the major allele (A) in rs1799978 for the DRD2 gene displayed reduced feelings of tension in response to exercise, while those with one or more minor alleles reported increased tension (AA: −4.69 ± 0.89 vs AG or GG: + 2.25 ± 2.16, P < 0.005). Homozygotes for the major alleles in rs151948, rs1362570, and rs1799978 (for BDNF, FTO, & DRD2 genes, respectively) served as strong predictors for changes in feelings of tension following exercise, controlling for gender and exercise parameters (P < 0.001). Subjects with one or more minor alleles (A) in rs1800498 for DRD2 gene displayed greater increases in hunger in response to exercise (AA or AG: 7.17 ± 0.85 vs GG: 3.96 ± 1.09, P < 0.03). ConclusionsSpecific gene polymorphisms, exercise intensity, duration, and gender may influence, in part, the variable mood response to exercise. Funding SourcesFunding for this research was provided by the National Institute of Diabetes and Digestive and Kidney Diseases of the National Institutes of Health Grant.

Glycaemic and insulinaemic impact of oats soaked overnight in milk vs. cream of rice with and without sugar, nuts, and seeds: a randomized, controlled trial

Background/ObjectivesSoaking oats overnight in milk renders them ready to eat the next morning, however, it is unknown whether oats prepared this way will retain its relatively low glycaemic and insulinaemic impact. Therefore, we compared the glycaemic, insulinaemic and subjective hunger responses elicited by oats soaked overnight in 110 g skim-milk (ONO) vs. cooked cream of rice cereal (CR), both with and without inclusions.Subjects/MethodsThe project was performed at two research centers (Toronto, Winnipeg) as two separate studies each using a randomized, cross-over design with similar methods. The glycaemic and insulinaemic responses of overnight-fasted participants without diabetes (males:females: Toronto, 24:16; Winnipeg, 20:20) were measured for 3 h after consuming CR and ONO fed alone (Toronto) or with added sugar, nuts, and seeds (CRsns and ONOsns) (Winnipeg). Participants rated subjective hunger using visual analog scales. Data were analyzed by paired t-test. The primary endpoint was 0–2 h incremental area under the curve (iAUC) for glucose.ResultsMean glucose iAUC was 33% less, after ONO than CR (mean difference was 39 (51–27) mmol × min/l, p < 0.0001) and 24% less, after ONOsns than CRsns (mean difference was 43 (65–21) mmol × min/l, p = 0.0003). Serum-insulin iAUC was 33% less, after ONO than CR (mean difference 57 (81–40) pmol × hl, p < 0.0001) and 32% less, after ONOsns than CRsns (966 (1360–572) pmol × h/l, p < 0.0001). In both Toronto and Winnipeg, subjective hunger ratings were similar across the two treatments.ConclusionsOats prepared by soaking overnight in skimmed milk without and with inclusions retain their relatively low glycaemic and insulinaemic impact.

Hunger and Satiety Signaling: Modeling Two Hypothalamomedullary Pathways for Energy Homeostasis.

The recent discovery of the medullary circuit driving "hunger responses" - reduced thermogenesis and promoted feeding - has greatly expanded our knowledge on the central neural networks for energy homeostasis. However, how hypothalamic hunger and satiety signals generated under fasted and fed conditions, respectively, control the medullary autonomic and somatic motor mechanisms remains unknown. Here, in reviewing this field, we propose two hypothalamomedullary neural pathways for hunger and satiety signaling. To trigger hunger signaling, neuropeptide Y activates a group of neurons in the paraventricular hypothalamic nucleus (PVH), which then stimulate an excitatory pathway to the medullary circuit to drive the hunger responses. In contrast, melanocortin-mediated satiety signaling activates a distinct group of PVH neurons, which then stimulate a putatively inhibitory pathway to the medullary circuit to counteract the hunger signaling. The medullary circuit likely contains inhibitory and excitatory premotor neurons whose alternate phasic activation generates the coordinated masticatory motor rhythms to promote feeding.

Medullary reticular GABAergic neurons that mediate hunger responses induced by hypothalamic neuropeptide Y

Hunger stimulates release of neuropeptide Y (NPY) in the paraventricular hypothalamus (PVH) from nerves derived from the arcuate nucleus. The NPY action in the PVH reduces energy expenditure through inhibition of brown adipose tissue (BAT) thermogenesis and stimulates food intake—hunger responses to survive starvation. However, the central circuit mechanism by which the NPY‐mediated hunger signaling from the hypothalamus coordinates the autonomic and somatic motor systems to reduce energy expenditure and to drive the consummatory responses is unknown. In this study, using rats and mice, we found that hypothalamic action of NPY activates GABAegic neurons in the intermediate and parvicellular reticular nuclei (IRt/PCRt) of the medulla oblongata that project to the rostral medullary raphe, which contains sympathetic premotor neurons controlling BAT thermogenesis. Selective stimulation of GABAergic neurons in the IRt/PCRt with a chemogenetic technique inhibited cooling‐induced BAT thermogenesis. Inactivation of IRt/PCRt neurons eliminated the inhibitory effect of NPY action in the PVH on cooling‐induced BAT thermogenesis. Intriguingly, the GABAergic IRt/PCRt neurons innervating the BAT sympathetic premotor region also innervated the masticatory motor region, and stimulation of the IRt/PCRt elicited mastication and increased feeding as well as inhibition of BAT thermogenesis. These results demonstrate a hunger response central circuit in which NPY‐triggered signaling from the hypothalamus activates GABAergic IRt/PCRt neurons, which then inhibit the thermogenic sympathetic premotor drive to BAT to reduce energy expenditure and stimulate a masticatory motor drive for feeding.Support or Funding InformationGrants‐in‐Aid for Scientific Research from MEXT, Japan (16H05128, 15H05932 &amp; 15K21744 to KN, 26290002 &amp; 15H01415 to YY, 26860159 to YN); NIH grant (R01NS40987 to SFM); Takeda Science Foundation (KN &amp; YY); Uehara Memorial Foundation (KN).

Medullary Reticular Neurons Mediate Neuropeptide Y-Induced Metabolic Inhibition and Mastication

Hypothalamic neuropeptide Y (NPY) elicits hunger responses to increase the chances of surviving starvation: an inhibition of metabolism and an increase in feeding. Here we elucidate a key central circuit mechanism through which hypothalamic NPY signals drive these hunger responses. GABAergic neurons in the intermediate and parvicellular reticular nuclei (IRt/PCRt) of the medulla oblongata, which are activated by NPY-triggered neural signaling from the hypothalamus, potentially through the nucleus tractus solitarius, mediate the NPY-induced inhibition of metabolic thermogenesis in brown adipose tissue (BAT) via their innervation of BAT sympathetic premotor neurons. Intriguingly, the GABAergic IRt/PCRt neurons innervating the BAT sympathetic premotor region also innervate the masticatory motor region, and stimulation of the IRt/PCRt elicits mastication and increases feeding as well as inhibits BAT thermogenesis. These results indicate that GABAergic IRt/PCRt neurons mediate hypothalamus-derived hunger signaling by coordinating both autonomic and feeding motor systems to reduce energy expenditure and to promote feeding.

What a difference a day makes: differences in initial abstinence response during a smoking cessation attempt.

To (1) identify distinct classes of smokers based on quit day withdrawal symptoms and (2) explore the relations between withdrawal classes and demographics, tobacco dependence, treatment and smoking outcomes. Secondary data analysis of participants (n=1504) in a randomized double-blind placebo-controlled multi-site smoking cessation trial who provided ecological momentary assessments of withdrawal symptoms on their quit day. Participants received smoking cessation counseling and were randomized to receive placebo or one of five active pharmacotherapies. Research offices in Madison and Milwaukee, Wisconsin, USA. Adult smokers (n=1236; 58% female, 86% white), recruited from the community via advertisements, who abstained on their quit day. Demographics and tobacco dependence were assessed at baseline and participants carried palmtop computers to record withdrawal symptoms (craving, negative affect, difficulty concentrating, hunger and anhedonia) on their quit day. Point-prevalence abstinence and latency to relapse were assessed at 8 weeks and 6 months post-quit. Latent class analysis identified four withdrawal classes [Akaike information criterion (AIC)=70.09]: Moderate withdrawal (64% of sample), high craving-anhedonia (8% of sample), affective withdrawal (13% of sample) and hunger (15% of sample). The high craving-anhedonia class reported significantly higher dependence (P<0.01), were less likely to have received combination nicotine replacement, reported lower week 8 abstinence rates and relapsed sooner than those in the moderate withdrawal class (P<0.05). The affective withdrawal class reported higher levels of baseline negative affect and life-time psychopathology (P<0.05) and relapsed more quickly than the moderate withdrawal class (P<0.01). While the majority of smokers report typical levels of withdrawal symptoms on their quit day, more than one-third report extreme craving or extreme negative affective or extreme hunger responses to initial abstinence. These distinct quit-day withdrawal symptom patterns are related to baseline characteristics, treatment and cessation success.

Mindfulness and eating behavior in adolescent girls at risk for type 2 diabetes

The purpose of this investigation was to examine the relationship of dispositional mindfulness to binge eating and associated eating attitudes and behaviors among adolescent girls at risk for type 2 diabetes (T2D). Participants were 114 overweight or obese adolescents enrolled in a study of girls with a family history of T2D and mild depressive symptoms. Adolescent self-reports of mindfulness, eating in the absence of hunger, and depressive symptoms were collected. An interview was administered to determine presence of binge eating episodes and a behavioral task was used to assess the reinforcing value of food relative to other nonsnack food rewards. Body composition was assessed using dual-energy X-ray absorptiometry. In analyses accounting for race, percent body fat, lean mass, height, age, and depressive symptoms, dispositional mindfulness was associated with a lower odds of binge eating (p = .002). Controlling for the same potential confounds, mindfulness was also inversely associated with eating concern, eating in the absence of hunger in response to fatigue/boredom, and higher food reinforcement relative to physical activity (all p < .05). In girls with a family history of T2D, independent of body composition and depressive symptoms, intraindividual differences in mindfulness are related to binge eating and associated attitudes and behaviors that may confer risk for obesity and metabolic problems. Further research is needed to determine the extent to which mindfulness plays a role in the etiology and/or maintenance of disinhibited eating in adolescents at risk for T2D.