Evidence for a compulsive-like behavior in rats exposed to alternate access to highly preferred palatable food.

Converging evidence suggests that recurrent excessive calorie restriction causes binge eating by promoting behavioral disinhibition and overeating. This interpretation suggests that cognitive adaptations may surpass physiological regulations of metabolic needs after recurrent cycles of dieting and binging. Intermittent access to palatable food has long been studied in rats, but the consequences of such diet cycling procedures on the cognitive control of food seeking remain unclear. Female Wistar rats were divided in two groups matched for food intake and body weight. One group received standard chow pellets 7 days/week, whereas the second group was given chow pellets for 5 days and palatable food for 2 days over seven consecutive weeks. Rats were also trained for operant conditioning. Intermittent access to palatable food elicited binging behavior and reduced intake of normal food. Rats with intermittent access to palatable food failed to exhibit anxiety-like behaviors in the elevated plus maze, but displayed reduced locomotor activity in the open field and developed a blunted corticosterone response following an acute stress across the diet procedure. Trained under a progressive ratio schedule, both groups exhibited the same motivation for sweetened food pellets. However, in contrast to controls, rats with a history of dieting and binging exhibited a persistent compulsive-like behavior when access to preferred pellets was paired with mild electrical foot shock punishments. These results highlight the intricate development of anxiety-like disorders and cognitive deficits leading to a loss of control over preferred food intake after repetitive cycles of intermittent access to palatable food.

Optogenetic Interrogation of Dopaminergic Modulation of the Multiple Phases of Reward-Seeking Behavior.

Phasic activation of dopaminergic neurons is associated with reward-predicting cues and supports learning during behavioral adaptation. While noncontingent activation of dopaminergic neurons in the ventral tegmental are (VTA) is sufficient for passive behavioral conditioning, it remains unknown whether the phasic dopaminergic signal is truly reinforcing. In this study, we first targeted the expression of channelrhodopsin-2 to dopaminergic neurons of the VTA and optimized optogenetically evoked dopamine transients. Second, we showed that phasic activation of dopaminergic neurons in freely moving mice causally enhances positive reinforcing actions in a food-seeking operant task. Interestingly, such effect was not found in the absence of food reward. We further found that phasic activation of dopaminergic neurons is sufficient to reactivate previously extinguished food-seeking behavior in the absence of external cues. This was also confirmed using a single-session reversal paradigm. Collectively, these data suggest that activation of dopaminergic neurons facilitates the development of positive reinforcement during reward-seeking and behavioral flexibility.

Addiction and arousal: the hypocretin connection

The hypocretins, also known as orexins, are two neuropeptides now commonly described as critical components to maintain and regulate the stability of arousal. Several lines of evidence have raised the hypothesis that hypocretin-producing neurons are part of the circuitries that mediate the hypothalamic response to acute stress. Intracerebral administration of hypocretin leads to a dose-related reinstatement of drug and food seeking behaviors. Furthermore, stress-induced reinstatement can be blocked with hypocretin receptor 1 antagonism. These results, together with recent data showing that hypocretin is critically involved in cocaine sensitization through the recruitment of NMDA receptors in the ventral tegmental area, strongly suggest that activation of hypocretin neurons play a critical role in the development of the addiction process. The activity of hypocretin neurons may affect addictive behavior by contributing to brain sensitization or by modulating the brain reward system. Hypocretinergic cells, in coordination with brain stress systems may lead to a vulnerable state that facilitates the resumption of drug seeking behavior. Hence, the hypocretinergic system is a new drug target that may be used to prevent relapse of drug seeking

Long-Lasting Metabolic Imbalance Related to Obesity Alters Olfactory Tissue Homeostasis and Impairs Olfactory-Driven Behaviors.

Obesity is associated with chronic food intake disorders and binge eating. Food intake relies on the interaction between homeostatic regulation and hedonic signals among which, olfaction is a major sensory determinant. However, its potential modulation at the peripheral level by a chronic energy imbalance associated to obese status remains a matter of debate. We further investigated the olfactory function in a rodent model relevant to the situation encountered in obese humans, where genetic susceptibility is juxtaposed on chronic eating disorders. Using several olfactory-driven tests, we compared the behaviors of obesity-prone Sprague-Dawley rats (OP) fed with a high-fat/high-sugar diet with those of obese-resistant ones fed with normal chow. In OP rats, we reported 1) decreased odor threshold, but 2) poor olfactory performances, associated with learning/memory deficits, 3) decreased influence of fasting, and 4) impaired insulin control on food seeking behavior. Associated with these behavioral modifications, we found a modulation of metabolism-related factors implicated in 1) electrical olfactory signal regulation (insulin receptor), 2) cellular dynamics (glucorticoids receptors, pro- and antiapoptotic factors), and 3) homeostasis of the olfactory mucosa and bulb (monocarboxylate and glucose transporters). Such impairments might participate to the perturbed daily food intake pattern that we observed in obese animals.

An assessment of obesity and hyperphagia in individuals with Smith-Magenis syndrome

Smith-Magenis syndrome (SMS;OMIM# 182290) is a multiple congenital anomalies and mental retardation syndrome caused by a 3.7- Mb deletion on chromosome 17p11.2 or a mutation in the RAI1 gene. Although the majority of the SMS phenotype has been well described, limited studies are available describing growth patterns in SMS. There is some evidence that individuals with SMS develop obesity. Thus, this study aims to characterize the growth and potential influence of hyperphagia in a cohort of individuals with SMS. A retrospective chart review was conducted of 78 individuals with SMS through Baylor College of Medicine (BCM) at Texas Children¡¯s Hospital (TCH.) All documented height and weight measurements were abstracted and Z-scores (SD units) for height-for-age, length-for-age and BMI-for-age were calculated. Mail-out questionnaires were provided to the corresponding parents of the cohort to assess for the presence of hyperphagia through a validated hyperphagia questionnaire (HQ). Analysis of this data demonstrates that by the age ¡Ý 20 years males with SMS have mean BMI¡¯s in the 85th-90th percentile corresponding to an overweight BMI, and females with SMS had mean BMI¡¯s in the 95th -97th percentile corresponding to an obese BMI. Parents indicated that hyperphagia is present in individuals with SMS as 76% of parent¡¯s report having to lock food away from their child. Females¡¯ age ¡Ý 20 years of age had the highest mean behavior, drive and severity scores as well as the highest BMI. Thus, this study concludes that it appears overweight and obesity, as well as hyperphagia, are present in this cohort of SMS individuals. The results of this study will hopefully enable parents and caregivers of children with SMS to take preventative measures in order to control food related behaviors present in their children as well as to prevent overweight and obesity and the associated negative health consequences.

Activité physique et récompense : impact de la leptine et de la signalisation STAT3 dans les neurones dopaminergiques

La course d’endurance active le système de récompense (SR) et est reliée aux comportements de recherche alimentaire. L’influence de la leptine sur l’activité physique (AP) volontaire est bien documentée d’un point de vue physiologique, mais très peu en termes d’impact hédonique. La leptine inhibe l’effet récompensant lié à la consommation de nourriture et joue un rôle semblable pour d’autres types de stimuli. La leptine s’arrime à la forme longue du récepteur à la leptine (Leprb) situé sur les neurones à dopamine (DA) et GABA de l’aire tegmentale ventrale (ATV) dans le mésencéphale. Signal transducer and Activator of Transcription 3 (STAT3) est un facteur de transcription important de la cascade de signalisation de la leptine. La phosphorylation de STAT3 n’est détectée que dans une parcelle des neurones DA positifs pour le Leprb, conférant aux neurones DA STAT3-spécifiques des caractéristiques uniques. Nous avons généré un modèle murin invalidé pour STAT3 sélectivement dans les neurones DA (STAT3DAT-KO). La première expérience consistait à évaluer les paramètres métaboliques de base de notre modèle en utilisant les chambres métaboliques Comprehensive Lab Animal Monitoring System (CLAMS), incluant l’activité ambulatoire, le ratio d’échanges respiratoires (RER) et la production de chaleur. Les STAT3DAT-KO sont hyperactives, démontré par une activité locomotrice augmentée, mais aucune variation entre les deux groupes n’est observée pour le RER et la production de chaleur, en plus d’un gain de poids identique. Une stratégie de récupération ciblant la réinsertion de STAT3 dans les neurones DA du système mésolimbique normalise l’AP anciennement plus élevée des STAT3DAT-KO à celle des contrôles, suivant l’accès libre à une roue d’exercice (RE) pour une durée de 4 semaines, suivant l’accès libre à une roue d’exercice (RE) pour une durée de 4 semaines. L’injection d’un psychostimulant (agoniste du récepteur DA de type 1 (D1R), le Chloro-APB-Hydrobromide (SKF 82958)) reflète une fonction dopaminergique réduite chez les STAT3DAT-KO. Un test de recherche compulsive de nourriture révèle une suppression de la prise alimentaire chez les deux groupes expérimentaux. Nous démontrons pour la première fois que la motivation alliée à la course d’endurance, indépendamment de la régulation de la prise alimentaire par la leptine, est dépendant d’une signalisation leptine-STAT3 amoindrie dans les neurones DA du système mésolimbique, révélant STAT3 comme élément clé dans la régulation du tonus dopaminergique et des propriétés récompensantes de l’AP.

Activité physique et récompense : impact de la leptine et de la signalisation STAT3 dans les neurones dopaminergiques

La course d’endurance active le système de récompense (SR) et est reliée aux comportements de recherche alimentaire. L’influence de la leptine sur l’activité physique (AP) volontaire est bien documentée d’un point de vue physiologique, mais très peu en termes d’impact hédonique. La leptine inhibe l’effet récompensant lié à la consommation de nourriture et joue un rôle semblable pour d’autres types de stimuli. La leptine s’arrime à la forme longue du récepteur à la leptine (Leprb) situé sur les neurones à dopamine (DA) et GABA de l’aire tegmentale ventrale (ATV) dans le mésencéphale. Signal transducer and Activator of Transcription 3 (STAT3) est un facteur de transcription important de la cascade de signalisation de la leptine. La phosphorylation de STAT3 n’est détectée que dans une parcelle des neurones DA positifs pour le Leprb, conférant aux neurones DA STAT3-spécifiques des caractéristiques uniques. Nous avons généré un modèle murin invalidé pour STAT3 sélectivement dans les neurones DA (STAT3DAT-KO). La première expérience consistait à évaluer les paramètres métaboliques de base de notre modèle en utilisant les chambres métaboliques Comprehensive Lab Animal Monitoring System (CLAMS), incluant l’activité ambulatoire, le ratio d’échanges respiratoires (RER) et la production de chaleur. Les STAT3DAT-KO sont hyperactives, démontré par une activité locomotrice augmentée, mais aucune variation entre les deux groupes n’est observée pour le RER et la production de chaleur, en plus d’un gain de poids identique. Une stratégie de récupération ciblant la réinsertion de STAT3 dans les neurones DA du système mésolimbique normalise l’AP anciennement plus élevée des STAT3DAT-KO à celle des contrôles, suivant l’accès libre à une roue d’exercice (RE) pour une durée de 4 semaines, suivant l’accès libre à une roue d’exercice (RE) pour une durée de 4 semaines. L’injection d’un psychostimulant (agoniste du récepteur DA de type 1 (D1R), le Chloro-APB-Hydrobromide (SKF 82958)) reflète une fonction dopaminergique réduite chez les STAT3DAT-KO. Un test de recherche compulsive de nourriture révèle une suppression de la prise alimentaire chez les deux groupes expérimentaux. Nous démontrons pour la première fois que la motivation alliée à la course d’endurance, indépendamment de la régulation de la prise alimentaire par la leptine, est dépendant d’une signalisation leptine-STAT3 amoindrie dans les neurones DA du système mésolimbique, révélant STAT3 comme élément clé dans la régulation du tonus dopaminergique et des propriétés récompensantes de l’AP.

Chemical characterization of leaves of organically grown carrot Dacus carota L.) in various stages of development for use as food

In Brazil, street markets and vegetable distributors discard vegetable leaves and stems, including those of carrot (Dacus carota L.). Seeking to reduce the waste of vegetable parts, this study characterized chemically the leaves of organically grown carrot in three stages of development to determine the best time for their removal and consumption as food. The leaves were dehydrated in an oven at 70 °C for 43 hours and analyzed for chemical composition, antioxidant activity, chlorophyll content, fatty acid composition, and also calcium (Ca), sodium (Na), potassium (K), magnesium (Mg), manganese (Mn), iron (Fe), zinc (Zn), and copper (Cu) contents. The analyses indicated 100 days of development as the ideal stage for the removal and consumption of carrot leaves with good antioxidant activity requiring only 63.78 ± 0.5 mg.L-1 methanol leaf extract to inhibit 50% of the concentration of the free radical DPPH (2,2-diphenyl-1picrilidrazil), and total protein and alpha-linolenic acid (18:3 n-3/LNA) contents of 18.23% ± 2.8 and 876.55 ± 20.62 mg.100 g-1 of dry matter, respectively.

Food crop diversification as a risk mitigating strategy during conflict : evidence from Cote d'Ivoire

This study examines the significance of food crop diversification as a household risk mitigating strategy to achieve "self-sufficiency" to ensure food security during the civil conflict in Cote d’Ivoire. The main motivation for seeking self-sufficiency stems from the fact that during the period of heightened tension due to conflict, the north–south divide set by the UN peacekeeping line disrupted the agricultural supply chain from the food surplus zone, Savane in the north. While we theoretically predict a positive effect on crop diversification because of interrupted food supply chain, we also consider a negative effect due to the covariate shocks. We find robust and statistically significant empirical outcomes supporting such claims. The baseline outcomes withstand a series of robustness checks. The net effect of conflict on crop diversification is positive but not statistically significant. In addition, we find that increasing vulnerability to poverty and food insecurity during conflict seems to be the underlying factors that motivate farm households to adopt such coping strategies.

Quality of life, stress and mental health in parents of children with parentally diagnosed food allergy compared to medically diagnosed and healthy controls

Background. Food allergy is related to poorer quality of life (QoL) and mental health of caregivers. Many parents diagnose food allergy in their child without seeking medical care and there is limited research on this group. This study investigated parental QoL and mental health in parents of children with parent-diagnosed food allergy (PA), medically diagnosed food allergy (MA), and a control group with no allergy (NA). Methods. One hundred and fifty parents from a general population completed validated measures of QoL, anxiety, depression, and stress. Results. Parents of children with food allergy (PA or MA) reported higher stress, anxiety, and depression than the control group (all ). Parents of children with MA reported poorer food allergy related QoL compared to parents of children with PA (); parents of children with PA reported poorer general QoL compared to parents of children with MA (). Conclusion. Parents of children with food allergy have significantly poorer mental health compared to healthy controls, irrespective of whether food allergy is medically diagnosed or not. It is important to encourage parents to have their child medically tested for food allergy and to recognise and refer for psychological support where needed.

The transition movement and food sovereignty: from local resilience to global engagement in food system transformation

The emergence of grassroots social movements variously preoccupied with a range of external threats, such as diminishing supplies of fossil energy or climate change, has led to increased interest in the production of local food. Drawing upon the notion of cognitive praxis, this article utilises transition as a trajectory guided by an overarching cosmology that brings together a broad social movement seeking a more resilient future. This ‘grand narrative’ is reinforced by ‘transition movement intellectuals’ who serve to shape an agenda of local preparedness in the face of uncertainty, rather than structural analysis of the global system. In this context, growing and producing food offers important multi-functional synergies by reconnecting people to place and its ecological endowments and serves to provide a vital element in civic mobilisation. Yet, local food could also become a means to build international solidarity in defence of food sovereignty and establish a global coalition opposed to the corporate agri-food agenda of biotechnologies, land grabbing and nutritional impoverishment.

Point-and-shoot: rapid quantitative detection methods for on-site food fraud analysis – moving out of the laboratory and into the food supply chain

Major food adulteration and contamination events occur with alarming regularity and are known to be episodic, with the question being not if but when another large-scale food safety/integrity incident will occur. Indeed, the challenges of maintaining food security are now internationally recognised. The ever increasing scale and complexity of food supply networks can lead to them becoming significantly more vulnerable to fraud and contamination, and potentially dysfunctional. This can make the task of deciding which analytical methods are more suitable to collect and analyse (bio)chemical data within complex food supply chains, at targeted points of vulnerability, that much more challenging. It is evident that those working within and associated with the food industry are seeking rapid, user-friendly methods to detect food fraud and contamination, and rapid/high-throughput screening methods for the analysis of food in general. In addition to being robust and reproducible, these methods should be portable and ideally handheld and/or remote sensor devices, that can be taken to or be positioned on/at-line at points of vulnerability along complex food supply networks and require a minimum amount of background training to acquire information rich data rapidly (ergo point-and-shoot). Here we briefly discuss a range of spectrometry and spectroscopy based approaches, many of which are commercially available, as well as other methods currently under development. We discuss a future perspective of how this range of detection methods in the growing sensor portfolio, along with developments in computational and information sciences such as predictive computing and the Internet of Things, will together form systems- and technology-based approaches that significantly reduce the areas of vulnerability to food crime within food supply chains. As food fraud is a problem of systems and therefore requires systems level solutions and thinking.

[food Insecurity In Brazilian Families With Children Under Five Years Of Age].

This article analyzes food insecurity and hunger in Brazilian families with children under five years of age. This was a nationally representative cross-sectional study using data from the National Demographic and Health Survey on Women and Children (PNDS-2006), in which the outcome variable was moderate to severe food insecurity, measured by the Brazilian Food Insecurity Scale (EBIA). Prevalence estimates and prevalence ratios were generated with 95% confidence intervals. The results showed a high prevalence of moderate to severe food insecurity, concentrated in the North and Northeast regions (30.7%), in economic classes D and E (34%), and in beneficiaries of conditional cash transfer programs (36.5%). Multivariate analysis showed that the socioeconomic relative risks (beneficiaries of conditional cash transfers), regional relative risks (North and Northeast regions), and economic relative risks (classes D and E) were 1.8, 2.0 and 2.4, respectively. Aggregation of the three risks showed 48% of families with moderate to severe food insecurity, meaning that adults and children were going hungry during the three months preceding the survey.

Evaluation Of The Location Of Capsules Swallowed With Food During The Pharyngeal Phase Triggering In Asymptomatic Adults.

To assess the location of hard gelatin capsules in the pharyngeal phase triggering among asymptomatic adults. The location of the bolus during the pharyngeal phase triggering provides information about the sensorimotor model of the beginning of deglutition onset. To evaluate the location of hard gelatin capsules in the pharyngeal phase triggering among asymptomatic adults. A videofluoroscopy swallowing study was carried out in 60 subjects (14 male and 46 female participants) aged between 27 and 55 years, who were evaluated with hard gelatin capsules #00 and #3 containing barium sulfate, swallowed with liquid food and pudding, in free volume. The first laryngeal elevation movement was the criterion to locate the pharyngeal phase triggering. Statistical analysis was based on the McNemar test. Capsule #3 presented higher percentage of location in the tongue dorsum compared to capsule #00, and capsule #00 presented higher percentage of location in the tongue base and vallecula compared to capsule #3. There was a difference between different capsules swallowed with liquid (p=0.016) and pudding (p=0.037). The capsule size influenced the location of the pharyngeal phase triggering. Smaller capsules started pharyngeal phase in the most anterior region (tongue dorsum) compared to larger capsules.

Mechanisms Of Insulin Resistance In The Amygdala: Influences On Food Intake.

Obesity is increasing worldwide and is triggered, at least in part, by enhanced caloric intake. Food intake is regulated by a complex mechanism involving the hypothalamus and hindbrain circuitries. However, evidences have showing that reward systems are also important in regulating feeding behavior. In this context, amygdala is considered a key extra-hypothalamic area regulating feeding behavior in human beings and rodents. This review focuses on the regulation of food intake by amygdala and the mechanisms of insulin resistance in this brain area. Similar to the hypothalamus the anorexigenic effect of insulin is mediated via PI3K (phosphoinositide 3-kinase)/Akt (protein kinase B) pathway in the amygdala. Insulin decreases NPY (neuropeptide Y) and increases oxytocin mRNA levels in the amygdala. High fat diet and saturated fatty acids induce inflammation, ER (endoplasmic reticulum) stress and the activation of serine kinases such as PKCθ (protein kinase C theta), JNK (c-Jun N-terminal kinase) and IKKβ (inhibitor of nuclear factor kappa-B kinase beta) in the amygdala, which have an important role in insulin resistance in this brain region. Overexpressed PKCθ in the CeA (central nucleus of amygdala) of rats increases weight gain, food intake, insulin resistance and hepatic triglycerides content. The inhibition of ER stress ameliorates insulin action/signaling, increases oxytocin and decreases NPY gene expression in the amygdala of high fat feeding rodents. Those data suggest that PKCθ and ER stress are main mechanisms of insulin resistance in the amygdala of obese rats and play an important role regulating feeding behavior.