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2.
Artigo em Inglês | MEDLINE | ID: mdl-31614418

RESUMO

Reports surrounding the role of resistant starch (RS) on postprandial lipemia in humans are scarce. The aim of the present study is to examine the effects of resistant starch on the postprandial lipemic response, subjective measures of appetite, and energy intake in overweight and obese subjects. In a randomized, single-blind, crossover study, 14 overweight/obese participants ate a high-fat breakfast (679 kcal, 58% from fat) and a supplement with native banana starch (NBS), high-amylose maize starch (HMS), or digestible maize starch (DMS) on three separate occasions. All supplements provided were matched by the available carbohydrate content, and the RS quantity in NBS and HMS supplements was identical. Appetite was estimated using visual analogue scale (VAS) and an ad libitum test meal. Postprandial glycemia, triglycerides, cholesterol, high-density lipoprotein (HDL) cholesterol, and insulin excursions did not differ between treatments. Subjective appetite measures of satiety were significantly increased after HMS; however, no effects on energy intake were observed during the ad libitum test meal. These findings suggest that a single acute dose of RS cannot be expected to improve postprandial lipemia in subjects with overweight or obesity on a high-fat meal. However, the potential benefits of long-term supplementation should not be ruled out based on these results.


Assuntos
Apetite/fisiologia , Ingestão de Alimentos/fisiologia , Hiperlipidemias/fisiopatologia , Obesidade/fisiopatologia , Saciação/fisiologia , Amido/administração & dosagem , Amido/metabolismo , Adulto , Estudos Cross-Over , Feminino , Humanos , Masculino , México , Período Pós-Prandial , Método Simples-Cego , Adulto Jovem
3.
Obes Facts ; 12(5): 529-542, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31494654

RESUMO

OBJECTIVE: Current evidence suggests that obesity is associated with alteration of sweet taste perception. The purpose of this study was to determine if nonsurgical cognitive behavioral therapy (CBT)-based weight loss can cause a change in sweet taste perception. METHODS: This case-control study consisted of 51 women aged 21-64 years. Twenty-seven with obesity or overweight were assigned to an obesity (OB) group (BMI: 29.8 ± 0.5 kg/m2) and 24 to a normal control (NC) group (BMI: 20.9 ± 0.3 kg/m2). The OB group underwent a 30-week weight loss intervention using CBT-based group therapy. The results of measurement of detection threshold, suprathreshold perceived intensity, preference, and palatability, elements of sweet taste perception, were compared before and after the intervention. Psychological variables and appetite-related hormonal levels were measured. RESULTS: Twenty-three patients and 22 controls completed the study. The OB group showed a 14.6% weight loss after the intervention. At baseline, the OB group preferred significantly higher sucrose concentrations than did the NC group; however, this difference was no longer significant after intervention. In the OB group, persistent pleasure and reduced desire for other taste, measured by repeated exposure to sweetness, normalized after weight loss to levels comparable to those seen in the NC group. No significant difference in discriminative perception of the threshold concentration or the suprathreshold sensory value was found between the two groups before or after intervention. A significant correlation was found between the basal preferred sucrose concentration and the serum leptin level of the OB group after adjusting for confounding factors, such as BMI, depressive symptom score, and trait-anxiety scores. CONCLUSIONS: Weight loss induced by CBT-based nonsurgical intervention resulted in the normalization of the sucrose preference and palatability of women with obesity. Leptin activity may be associated with the altered sweet taste preference of people with obesity.


Assuntos
Terapia Cognitivo-Comportamental , Preferências Alimentares/psicologia , Obesidade/terapia , Percepção Gustatória/fisiologia , Paladar , Perda de Peso/fisiologia , Adulto , Apetite/fisiologia , Estudos de Casos e Controles , Terapia Cognitivo-Comportamental/métodos , Fissura/fisiologia , Açúcares da Dieta/administração & dosagem , Feminino , Preferências Alimentares/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/fisiopatologia , Obesidade/psicologia , Sobrepeso/fisiopatologia , Sobrepeso/psicologia , Sobrepeso/terapia , Prazer/fisiologia , Adulto Jovem
4.
Nat Commun ; 10(1): 3097, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31308381

RESUMO

Dopaminergic neurons in the brain of the Drosophila larva play a key role in mediating reward information to the mushroom bodies during appetitive olfactory learning and memory. Using optogenetic activation of Kenyon cells we provide evidence that recurrent signaling exists between Kenyon cells and dopaminergic neurons of the primary protocerebral anterior (pPAM) cluster. Optogenetic activation of Kenyon cells paired with odor stimulation is sufficient to induce appetitive memory. Simultaneous impairment of the dopaminergic pPAM neurons abolishes appetitive memory expression. Thus, we argue that dopaminergic pPAM neurons mediate reward information to the Kenyon cells, and in turn receive feedback from Kenyon cells. We further show that this feedback signaling is dependent on short neuropeptide F, but not on acetylcholine known to be important for odor-shock memories in adult flies. Our data suggest that recurrent signaling routes within the larval mushroom body circuitry may represent a mechanism subserving memory stabilization.


Assuntos
Encéfalo/fisiologia , Neurônios Dopaminérgicos/fisiologia , Drosophila melanogaster/fisiologia , Memória/fisiologia , Corpos Pedunculados/fisiologia , Recompensa , Acetilcolina/metabolismo , Animais , Apetite/fisiologia , Encéfalo/citologia , Condicionamento Clássico , Retroalimentação Fisiológica , Larva , Modelos Psicológicos , Corpos Pedunculados/citologia , Vias Neurais/fisiologia , Neuropeptídeos/metabolismo , Odorantes , Percepção Olfatória/fisiologia , Optogenética
5.
Elife ; 82019 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-31205005

RESUMO

Taste circuits are genetically determined to elicit an innate appetitive or aversive response, ensuring that animals consume nutritious foods and avoid the ingestion of toxins. We have examined the response of Drosophila melanogaster to acetic acid, a tastant that can be a metabolic resource but can also be toxic to the fly. Our data reveal that flies accommodate these conflicting attributes of acetic acid by virtue of a hunger-dependent switch in their behavioral response to this stimulus. Fed flies show taste aversion to acetic acid, whereas starved flies show a robust appetitive response. These opposing responses are mediated by two different classes of taste neurons, the sugar- and bitter-sensing neurons. Hunger shifts the behavioral response from aversion to attraction by enhancing the appetitive sugar pathway as well as suppressing the aversive bitter pathway. Thus a single tastant can drive opposing behaviors by activating distinct taste pathways modulated by internal state.


Assuntos
Ácido Acético/farmacologia , Drosophila melanogaster/efeitos dos fármacos , Comportamento Alimentar/efeitos dos fármacos , Células Receptoras Sensoriais/efeitos dos fármacos , Paladar/efeitos dos fármacos , Animais , Apetite/efeitos dos fármacos , Apetite/fisiologia , Drosophila melanogaster/fisiologia , Comportamento Alimentar/fisiologia , Fome/fisiologia , Vias Neurais/efeitos dos fármacos , Vias Neurais/fisiologia , Células Receptoras Sensoriais/fisiologia , Paladar/fisiologia
6.
Transl Psychiatry ; 9(1): 148, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31113931

RESUMO

Learning accounts of addiction and obesity emphasize the persistent power of Pavlovian reward cues to trigger craving and increase relapse risk. While extinction can reduce conditioned responding, Pavlovian relapse phenomena-the return of conditioned responding following successful extinction-challenge the long-term success of extinction-based treatments. Translational laboratory models of Pavlovian relapse could therefore represent a valuable tool to investigate the mechanisms mediating relapse, although so far human research has mostly focused on return of fear phenomena. To this end we developed an appetitive conditioning paradigm with liquid food rewards in combination with a 3-day design to investigate the return of appetitive Pavlovian responses and the involved neural structures in healthy subjects. Pavlovian conditioning (day 1) was assessed in 62 participants, and a subsample (n = 33) further completed extinction (day 2) and a reinstatement test (day 3). Conditioned responding was assessed on explicit (pleasantness ratings) and implicit measures (reaction time, skin conductance, heart rate, startle response) and reinstatement effects were further evaluated using fMRI. We observed a return of conditioned responding during the reinstatement test, evident by enhanced skin conductance responses, accompanied by enhanced BOLD responses in the amygdala. On an individual level, psychophysiological reinstatement intensity was significantly anticorrelated with ventromedial prefrontal cortex (vmPFC) activation, and marginally anticorrelated with enhanced amygdala-vmPFC connectivity during late reinstatement. Our results extend evidence from return of fear phenomena to the appetitive domain, and highlight the role of the vmPFC and its functional connection with the amygdala in regulating appetitive Pavlovian relapse.


Assuntos
Tonsila do Cerebelo/fisiologia , Apetite/fisiologia , Mapeamento Encefálico , Condicionamento Clássico/fisiologia , Córtex Pré-Frontal/fisiologia , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Feminino , Sucos de Frutas e Vegetais , Resposta Galvânica da Pele/fisiologia , Humanos , Imagem por Ressonância Magnética , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Desempenho Psicomotor/fisiologia , Reflexo de Sobressalto/fisiologia , Adulto Jovem
7.
Eur J Pharmacol ; 854: 119-127, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-30986399

RESUMO

Carvacrol, a monoterpene phenol present in the essential oil of oregano, possesses several biological properties, such as antioxidant, anti-inflammatory, anxiolytic, anticonvulsive and antinociceptive. In vitro studies have shown that carvacrol inhibits serotonin, noradrenaline and dopamine transporters and the enzymes monoamine oxidase-A and B. Different brain functions are controlled by monoamines, including cardiovascular control, thirst and sodium appetite. In the present study we investigated the effects of intracerebroventricular (i.c.v.) injection of carvacrol on sodium appetite, and the participation of brain serotonergic and noradrenergic pathways on carvacrol effects. Neuronal activation in homeostasis-related brain areas induced by i.c.v. injection of carvacrol was also evaluated. Carvacrol dose-dependently inhibited hypertonic saline intake (1.5%) in sodium-depleted rats, and this antinatriorexigenic effect was reduced by brain serotonergic depletion and by alpha-adrenergic blockade. Furthermore, i.c.v. injections of carvacrol significantly increased the neuronal activation in brain areas involved in the control of salt appetite, such as MnPO, OVLT, PVN, SON, CeA and MeA. Taken together, our data show that carvacrol presents antinatriorexigenic activity through serotonin and noradrenaline pathways within brain circuits involved in the modulation of the body fluid homeostasis.


Assuntos
Apetite/efeitos dos fármacos , Norepinefrina/metabolismo , Serotonina/metabolismo , Cloreto de Sódio/farmacologia , Animais , Apetite/fisiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Locomoção/efeitos dos fármacos , Masculino , Neurônios/citologia , Neurônios/efeitos dos fármacos , Prosencéfalo/citologia , Prosencéfalo/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-fos/genética , Ratos , Ratos Wistar
8.
Neurosci Lett ; 703: 184-190, 2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-30928477

RESUMO

This study analyzed the effects of LHb lesions on appetitive extinction and alcohol consumption. Eighteen male Wistar rats received neurochemical lesions of the LHb (quinolinic acid) and 12 received a vehicle infusion (PBS). In a runway instrumental task, rats received acquisition (12 pellets/trial, 6 trials/session, 10 sessions) and extinction training (5 sessions). In a consummatory task, rats had daily access to 32% sucrose (5 min, 10 sessions) followed by access to water (5 sessions). Then, animals received 2 h preference tests with escalating alcohol concentrations (2%-24%), followed by two 24 h preference tests with 24% alcohol. Relative to Shams, LHb lesions delayed extinction, as indicated by lower response latencies (instrumental task) and higher fluid consumption (consummatory task). LHb lesions did not affect alcohol consumption regardless of alcohol concentration or test duration. The LHb modulates appetitive extinction and needs to be considered as part of the brain circuit underlying reward loss.


Assuntos
Consumo de Bebidas Alcoólicas/psicologia , Apetite/fisiologia , Comportamento Apetitivo , Habenula/fisiologia , Consumo de Bebidas Alcoólicas/fisiopatologia , Animais , Extinção Psicológica , Masculino , Ratos Wistar
9.
J Affect Disord ; 250: 249-259, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30870775

RESUMO

BACKGROUND: Major depressive disorder (MDD) is a complex and heterogeneous disorder in which clinical symptoms can widely differ among patients. Neurovegetative symptoms, i.e. decreased or increased appetite, changes in body weight and sleep disturbances, described as 'melancholic' or 'atypical' features of a depressive episode, are the most variable symptoms among patients with MDD. We hypothesized biomarkers differences underlying this neurovegetative variability in major depression. METHODS: We systematically reviewed, according to the PRISMA guidelines, the role of specific metabolic, hormonal and inflammatory biomarkers in drug-free MDD patients, that could have neurobiological effects on appetite, weight regulation and circadian rhythms, influencing eating behaviour and sleep patterns. All studies regarding the co-occurrence of disturbed sleep and appetite were examined. RESULTS: Besides the well-known leptin and ghrelin, other biomarkers such as BDNF, VEGF, NPY, orexin, and the recent discovered nesfatin-1 seem to be involved in neurovegetative changes in depressive disorders playing a role in the regulation of affective states, stress reactions and sleep patterns. Interestingly, based on the existing evidence, ghrelin, orexin and nesfatin-1 could be linked both to sleep and appetite regulation in depressed patients. LIMITATIONS: Heterogeneous studies with low sample size. CONCLUSIONS: Despite the wide heterogeneity of results, studies on biomarkers of appetite and sleep in MDD are an interesting field of research to explain the neurobiological substrates of depressive symptoms that deserve further investigation.


Assuntos
Apetite/fisiologia , Biomarcadores/metabolismo , Transtorno Depressivo Maior/fisiopatologia , Metabolismo Energético/fisiologia , Hormônios/fisiologia , Mediadores da Inflamação/fisiologia , Sono/fisiologia , Transtorno Depressivo Maior/psicologia , Humanos
10.
Nutrients ; 11(3)2019 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-30909563

RESUMO

We aimed to investigate the effects of a wide range of daily physical activity (PA) levels on energy balance (EB), energy intake (EI), and appetite. Nine young men completed three different PA levels in a metabolic chamber in a random order: (1) no exercise (Low-PA); (2) 25 min walking seven times (Mid-PA); and (3) 25 min running seven times (High-PA) within a 24 h period. Interval exercise (25 min exercise and 35 min rest) was performed three times in the morning and four times in the afternoon. The exercise intensities were 21.6% and 53.7% V ˙ O2 peak for the Mid-PA and High-PA days, respectively. Participants were served three standardized meals and a buffet for dinner. The 24 h EB was calculated as 24 h energy expenditure (EE) minus 24 h EI. The 24 h EEs for the Low-PA, Mid-PA, and High-PA days were 1907 ± 200, 2232 ± 240, and 3224 ± 426 kcal, respectively, with significant differences observed among the three conditions (p < 0.01 for Low-PA vs. Mid-PA, Low-PA vs. High-PA, and Mid-PA vs. High-PA, respectively). The 24 h EIs for the Low-PA, Mid-PA, and High-PA days were 3232 ± 528, 2991 ± 617, and 3337 ± 684 kcal, and were unaffected by PA levels (p = 0.115). The 24 h EBs were 1324 ± 441 kcal (Low-PA), 759 ± 543 kcal (Mid-PA), and 113 ± 430 kcal (High-PA), with significant differences observed between Low-PA vs. Mid-PA (p = 0.0496), Low-PA vs. High-PA (p ≤ 0.01), and Mid-PA vs. High-PA (p = 0.017) conditions. The EB in the Low-PA group was the highest of the three conditions. Appetite perception did not differ among the study days, however there was an interaction trend (p = 0.078, time × condition). Thus, significantly different daily PA did not affect 24 h EI, however markedly affected 24 h EB, implying that EB is not automatically matched during a single day.


Assuntos
Apetite/fisiologia , Ingestão de Energia/fisiologia , Metabolismo Energético/fisiologia , Exercício/fisiologia , Refeições , Voluntários Saudáveis , Humanos , Masculino , Fatores de Tempo , Adulto Jovem
11.
Obesity (Silver Spring) ; 27(4): 629-635, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30900406

RESUMO

OBJECTIVE: Potential mechanisms of abnormal food intake, such as dysregulation of meal-related appetite hormones, including acyl ghrelin (AG) and des-acyl ghrelin (DAG), were investigated among men and women with obesity, with and without binge eating (BE). METHODS: Participants (n = 42: 19 female, 23 male) were assigned to a liquid meal and water condition in counterbalanced order, and blood samples for measuring hormones were obtained before and after these conditions. RESULTS: Participants with BE had significantly lower fasting and postingestive AG concentrations than participants without BE in both conditions. During the meal condition, postprandial decreases in AG concentrations were significantly smaller for the BE group than for the non-BE group. There were no significant differences in DAG by BE group. Leptin increased significantly less after meals for those with BE compared with those without BE. There were no differences in other hormones by BE group. Fasting and postmeal hunger ratings were significantly higher for those with BE than for those without BE. CONCLUSIONS: In individuals with BE, lower fasting AG may be due to downregulation by habitual overeating, and a smaller postmeal decline in AG may contribute to overeating. Lower postmeal leptin concentrations may also contribute to overeating.


Assuntos
Apetite/fisiologia , Bulimia/sangue , Ingestão de Alimentos/fisiologia , Grelina/sangue , Obesidade/sangue , Adulto , Transtorno da Compulsão Alimentar/sangue , Transtorno da Compulsão Alimentar/complicações , Bulimia/complicações , Colecistocinina/sangue , Feminino , Peptídeo 1 Semelhante ao Glucagon/sangue , Humanos , Hiperfagia/sangue , Hiperfagia/complicações , Insulina/sangue , Leptina/sangue , Masculino , Refeições , Pessoa de Meia-Idade , Obesidade/complicações , Peptídeo YY/sangue , Período Pós-Prandial/fisiologia , Adulto Jovem
12.
Ther Apher Dial ; 23(5): 437-443, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30701674

RESUMO

Loss of appetite affects one-third of patients with CKD and is the leading cause of malnutrition in this population. Orexigenic Agouti-related peptide (AgRP) with neuropeptide-Y (NPY) and anorexigenic melanocyte-stimulating hormone-α (MSH-α) with cocaine- and amphetamine-regulated transcript (CART) are known to regulate appetite. In this study, we aimed to evaluate the levels of these peptides in CKD patients compared to healthy subjects and demonstrate the effects of dialysis treatment and erythropoiesis-stimulating agent (ESA) therapy. The cross-sectional study is composed of consecutive inclusion of 20 healthy individuals, 20 predialysis CKD patients, 20 HD, and 20 peritoneal dialysis (PD) patients. Exclusion criteria were an active infection, history of malignancy, hypo- or hyperthyroidism, and diabetes. Patients on dialysis had targeted Kt/Vs. Demographic features and BMIs of the four groups were similar. Levels of AgRP, NPY, AMSH, and CART were significantly different between groups. Nondialysis CKD patients had significantly lower hypothalamic hormones compared to healthy individuals, HD and PD patients (P = 0.02, P = 0.03, and P = 0.07 for AgRP; P = 0.02, P = 0.01, and P = 0.09 for NPY; P = 0.02, P = 0.02, and P = 0.03 for AMSH; P = 0.02, P = 0.005, and P = 0.030 for CART). Dialysis patients with or without ESA treatment had similar hormone levels (P = 0.13 for AgRP; P = 0.11 for NPY; P = 0.23 for AMSH, and P = 019 for CART). Predialysis CKD patients have lower orexigenic and presumably indirectly lower anorexigenic peptides compared to healthy subjects and dialysis patients. ESA treatment does not affect these hypothalamic peptides in dialysis patients.


Assuntos
Apetite/fisiologia , Hipotálamo/metabolismo , Diálise Peritoneal/métodos , Insuficiência Renal Crônica/terapia , Adulto , Proteína Relacionada com Agouti/metabolismo , Estudos de Casos e Controles , Estudos Transversais , Feminino , Hematínicos/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/metabolismo , Neuropeptídeo Y/metabolismo , alfa-MSH/metabolismo
13.
Int Heart J ; 60(2): 384-391, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30799377

RESUMO

The physiological control of appetite regulation involves circulating hormones with orexigenic (ghrelin) and anorexigenic (cholecystokinin) properties that induce alterations in energy intake via perceptions of hunger and satiety. We sought to investigate the relationship between appetite-regulating hormones and the cachexia associated with chronic heart failure.We randomized male Sprague-Dawley rats into myocardial infarction (MI) or sham operation (SO) groups. The levels of brain natriuretic peptide (BNP), cholecystokinin (CCK) and ghrelin in the plasma of all rats were detected by enzyme-linked immunosorbent assay (ELISA); the expression of BNP, CCK, and ghrelin in the myocardial tissue of all rats were detected by western blotting, immunohistochemistry, real-time polymerase chain reaction (PCR); myocardial morphology was assessed by microscopy.Plasma BNP and CCK levels in the cardiac cachexia (CC) groups and the heart failure non-cachexia (HF-nc) groups were significantly higher than those in the control groups (P < 0.01), and the expression of BNP and CCK in the myocardial tissue of rats: in CC groups and HF-nc groups were increased compared with the corresponding control groups (P < 0.01). In contrast, Plasma and cardiac expression of ghrelin decreased compared with the sham group (P < 0.01). Furthermore, plasma CCK levels were positively correlated with BNP concentrations (P < 0.001) and significantly negatively correlated with the ejection fraction (P < 0.001) in model animals; plasma ghrelin levels were negatively associated with BNP levels (P = 0.0023) and positively associated with ejection fraction (P = 0.0042).The appetite-regulating hormones (ghrelin and CCK) may present as a potential significant biomarker for cachexia associated with chronic heart failure.


Assuntos
Apetite/fisiologia , Caquexia , Colecistocinina , Grelina , Insuficiência Cardíaca , Peptídeo Natriurético Encefálico , Animais , Biomarcadores/sangue , Biomarcadores/metabolismo , Caquexia/metabolismo , Caquexia/patologia , Caquexia/fisiopatologia , Colecistocinina/sangue , Colecistocinina/metabolismo , Correlação de Dados , Grelina/sangue , Grelina/metabolismo , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/fisiopatologia , Masculino , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Peptídeo Natriurético Encefálico/sangue , Peptídeo Natriurético Encefálico/metabolismo , Ratos , Ratos Sprague-Dawley , Volume Sistólico
14.
J Endocrinol ; 241(1): R1-R33, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30812013

RESUMO

The initial discovery that ob/ob mice become obese because of a recessive mutation of the leptin gene has been crucial to discover the melanocortin pathway to control appetite. In the melanocortin pathway, the fed state is signaled by abundance of circulating hormones such as leptin and insulin, which bind to receptors expressed at the surface of pro-opiomelanocortin (POMC) neurons to promote processing of POMC to the mature hormone α-melanocyte-stimulating hormone (α-MSH). The α-MSH released by POMC neurons then signals to decrease energy intake by binding to melanocortin-4 receptor (MC4R) expressed by MC4R neurons to the paraventricular nucleus (PVN). Conversely, in the 'starved state' activity of agouti-related neuropeptide (AgRP) and of neuropeptide Y (NPY)-expressing neurons is increased by decreased levels of circulating leptin and insulin and by the orexigenic hormone ghrelin to promote food intake. This initial understanding of the melanocortin pathway has recently been implemented by the description of the complex neuronal circuit that controls the activity of POMC, AgRP/NPY and MC4R neurons and downstream signaling by these neurons. This review summarizes the progress done on the melanocortin pathway and describes how obesity alters this pathway to disrupt energy homeostasis. We also describe progress on how leptin and insulin receptors signal in POMC neurons, how MC4R signals and how altered expression and traffic of MC4R change the acute signaling and desensitization properties of the receptor. We also describe how the discovery of the melanocortin pathway has led to the use of melanocortin agonists to treat obesity derived from genetic disorders.


Assuntos
Apetite/fisiologia , Melanocortinas/metabolismo , Neurônios/metabolismo , Pró-Opiomelanocortina/metabolismo , Transdução de Sinais/fisiologia , Animais , Fármacos Antiobesidade/farmacologia , Humanos , Camundongos , Obesidade/metabolismo , Obesidade/fisiopatologia , Obesidade/prevenção & controle , Núcleo Hipotalâmico Paraventricular/metabolismo , Peptídeos/farmacologia , Receptor Tipo 4 de Melanocortina/agonistas , Receptor Tipo 4 de Melanocortina/metabolismo , Transdução de Sinais/efeitos dos fármacos , alfa-MSH/metabolismo
15.
J Pediatr Endocrinol Metab ; 32(3): 275-280, 2019 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-30796846

RESUMO

Background It is known that iron deficiency anemia effects appetite and growth negatively. The aim of this study was to investigate the effect of iron therapy on appetite, growth and plasma ghrelin and leptin levels in children aged between 12 and 24 months with isolated nutritional iron deficiency anemia. Methods Iron deficiency anemia was diagnosed by clinic and laboratory findings. All 19 cases were given 5 mg/kg/day iron therapy for 3 months. Results The mean plasma ghrelin level was 936.7±428.8 pg/mL before therapy and it increased to 1284.7±533.3 pg/mL (p<0.001) while the mean plasma leptin level decreased from 3.4±1.6 ng/mL to 1.9±1.0 ng/mL (p<0.01) after therapy. The amount of daily caloric intake, carbohydrate and protein intake were significantly increased after therapy (p<0.001). Δ body weight was correlated with plasma ghrelin levels before and after therapy significantly. Conclusions In conclusion, the findings of this study indicate that plasma ghrelin level increases and leptin level decreases and growth accelerates because of an increase in appetite and daily calories, carbohydrate and protein amount in children with nutritional iron deficiency anemia after iron therapy. The increase in appetite and acceleration on growth in iron deficiency anemia might result from decreased leptin and increased plasma ghrelin levels. The most important finding of this study is significantly increased plasma ghrelin levels after iron therapy, and this finding might be related to both the improved appetite and catch-up growth.


Assuntos
Anemia Ferropriva/sangue , Anemia Ferropriva/tratamento farmacológico , Apetite/fisiologia , Grelina/sangue , Ferro/uso terapêutico , Leptina/sangue , Peso Corporal/efeitos dos fármacos , Feminino , Humanos , Lactente , Ferro/farmacologia , Masculino , Resultado do Tratamento
16.
Pediatr Obes ; 14(5): e12496, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30702799

RESUMO

BACKGROUND: Many genetic polymorphisms identified by genome-wide association studies for adult body mass index (BMI) have been suggested to regulate food intake. OBJECTIVE: The objective was to study the associations between a genetic obesity risk score, appetitive traits, and growth of children up to age 5 years, with a longitudinal design. METHODS: In 1142 children from the Etude des Déterminants pre et post natals de la santé de l'ENfant (EDEN) birth cohort, a combined obesity risk-allele score (BMI genetic risk score [GRS]) was related to appetitive traits (energy intake up to 12 mo, a single item on appetite from 4 mo to 3 y, a validated appetite score at 5 y) using Poisson regressions with robust standard errors. The potential mediation of appetitive traits on the association between BMI-GRS and growth was assessed by the Sobel test. RESULTS: Children with a high BMI-GRS were more likely to have high energy intake at 1 year and high appetite at 2 and 5 years. High energy intake in infancy and high appetite from 1 year were related to higher subsequent BMI. High 2-year appetite seemed to partially mediate the associations between BMI-GRS and BMI from 2 to 5 years (all P ≤ 0.05). CONCLUSIONS: Genetic susceptibility to childhood obesity seems to be partially explained by appetitive traits in infancy, followed by an early childhood rise in BMI.


Assuntos
Apetite/genética , Desenvolvimento Infantil/fisiologia , Comportamento Alimentar/fisiologia , Obesidade Pediátrica/genética , Adulto , Alelos , Apetite/fisiologia , Índice de Massa Corporal , Pré-Escolar , Estudos de Coortes , Ingestão de Alimentos , Ingestão de Energia , Feminino , França , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Técnicas de Genotipagem , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Mães , Gravidez , Estudos Prospectivos , Fatores de Risco
17.
Nutrients ; 11(2)2019 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-30764560

RESUMO

Gut appetite hormone responses may be influenced by meal macronutrients and obesity. The primary aim of this study was to examine in adolescents with obesity and of healthy weight the effect of a high-protein and a high-carbohydrate meal on postprandial gut appetite hormones. A postprandial cross-over study with adolescents 11⁻19 years old was undertaken. Participants consumed, in random order, a high 79% carbohydrate (HCHO) and a high 55% protein (HP) meal. Ghrelin, glucagon-like peptide 1 (GLP-1), peptide YY (PYY), and self-reported appetite were assessed for four hours postprandial. Total energy intake from an ad libitum lunch and remaining 24 h was assessed. Eight adolescents with obesity (OB) and 12 with healthy weight (HW) participated. Compared with HW, OB adolescents displayed a smaller ghrelin iAUC (-25,896.5 ± 7943 pg/mL/4 h vs. -60,863.5 ± 13104 pg/mL/4 h) (p = 0.008) with no effect of meal (p > 0.05). The suppression of ghrelin relative to baseline was similar between OB and HW. Ghrelin suppression was greater following the HP vs. HCHO meal (effect of meal, p = 0.018). Glucose and insulin response were greater following HCHO vs. HP, with responses more marked in OB (time × weight × meal interaction, p = 0.003 and p = 0.018, respectively). There were no effects of weight or macronutrient on GLP-1 or PYY, appetite or subsequent energy intake. The present study demonstrates that dietary protein can modulate postprandial ghrelin responses; however, this did not translate to subsequent changes in subjective appetite or energy intake.


Assuntos
Apetite/efeitos dos fármacos , Carboidratos da Dieta/farmacologia , Proteínas na Dieta/farmacologia , Nutrientes/farmacologia , Obesidade Pediátrica/metabolismo , Adolescente , Apetite/fisiologia , Criança , Estudos Cross-Over , Método Duplo-Cego , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Grelina/genética , Grelina/metabolismo , Peptídeo 1 Semelhante ao Glucagon/genética , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Humanos , Masculino , Peptídeo YY/genética , Peptídeo YY/metabolismo , Adulto Jovem
18.
Nutrients ; 11(2)2019 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-30691085

RESUMO

It is unclear whether sugar sweetened beverages bypass regulatory controls of food intake (FI) in boys. The objective of the present study was to determine the effects of isovolumetric preloads (350 mL) of a fruit-flavoured drink (154 kcal), cola (158 kcal), 1% M.F. chocolate milk (224 kcal), and water (0 kcal) on subjective appetite and FI in boys aged 9⁻14 years. On four separate mornings, boys consumed one of the preloads in a random order; subjective appetite was measured at 15 min intervals, and FI was measured via an ad libitum pizza lunch at 60 min post-beverage consumption. In the 32 boys (age: 11.8 ± 0.3 years), FI was reduced (p < 0.001) after cola (940 ± 46 kcal) and chocolate milk (878 ± 41 kcal) compared with the water control (1048 ± 35 kcal) and after chocolate milk compared to the fruit drink (1005 ± 44 kcal). Cumulative FI after the fruit drink was greater than the water control (1159 ± 44 vs. 1048 ± 35 kcal; p = 0.03). Average appetite was not affected by the treatment, but the cola treatment resulted in greater fullness (p = 0.04) and lower prospective food consumption (p = 0.004) compared with the fruit drink. In conclusion, chocolate milk and cola suppressed next-meal FI at 60 min, while fruit drink increased cumulative FI (beverage + next meal) over 60 min in boys. Results from this study suggest that beverage composition is an important determinant of FI suppression in boys.


Assuntos
Apetite/fisiologia , Bebidas , Dieta/estatística & dados numéricos , Ingestão de Alimentos/fisiologia , Adolescente , Criança , Açúcares da Dieta , Humanos , Masculino , Edulcorantes
19.
Domest Anim Endocrinol ; 67: 11-20, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30660023

RESUMO

Oxytocin (OT) is a well-characterized neurotransmitter that participates in a wide range of physiological processes including the inhibition of food intake. The avian ortholog, mesotocin (MT), differs from OT by a single amino acid. Little is known regarding the function of OT in regulating energy balance in birds; thus, this study was designed to determine the effects of central OT injection on food intake and adipose tissue physiology in chicks. At 4-d post-hatch, broiler chicks were fasted for 3 h and injected intracerebroventricularly with 0 (vehicle), 0.63, 2.5, 5.0, or 10 nmol OT. Oxytocin decreased food and water intake during the entire 180-min observation period. The reduction in water intake was likely not prandial because chicks that were food restricted after OT injection also drank less. There was increased c-Fos immunoreactivity in several appetite-associated hypothalamic nuclei in OT-injected chicks at 1 h, including the arcuate (ARC), dorsomedial nucleus (DMN), lateral hypothalamus (LH), paraventricular nucleus (PVN), and ventromedial hypothalamus (VMH). OT treatment was associated with reduced hypothalamic corticotropin-releasing factor (CRF) mRNA and increased cloacal temperature at 1 h post-injection. We then investigated appetite- and adipose tissue-associated effects of OT in chicks from lines that have undergone long-term selection for either low (LWS) or high (HWS) juvenile body weight. Central injection of OT decreased food intake in both lines with the magnitude of response greater in the HWS than LWS chicks. Adipose tissue abundance of fatty acid-binding protein 4, monoglyceride lipase (MGLL), MT, and perilipin-1 mRNA was greater in LWS than HWS chicks. Lipoprotein lipase, MGLL, and MT mRNAs increased in response to OT injection in LWS but not HWS chicks. In conclusion, central injection of OT induced anorexia, reduced water intake, increased body temperature, and was associated with activation of the ARC, DMN, LH, PVN, and VMH in the hypothalamus. The effects on appetite and body temperature may involve CRF signaling in the hypothalamus and lipolysis in the adipose tissue, respectively. There were differences in the appetite, and adipose tissue response to OT in body weight-selected lines of chicks supports that MT plays a role in energy balance regulation in chickens.


Assuntos
Tecido Adiposo/metabolismo , Galinhas/fisiologia , Ingestão de Alimentos/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Hipotálamo/metabolismo , Ocitocina/administração & dosagem , Tecido Adiposo/efeitos dos fármacos , Animais , Apetite/efeitos dos fármacos , Apetite/fisiologia , Temperatura Corporal/efeitos dos fármacos , Peso Corporal , Hormônio Liberador da Corticotropina/genética , Ingestão de Líquidos/efeitos dos fármacos , Ingestão de Alimentos/fisiologia , Metabolismo Energético/fisiologia , Jejum , Hipotálamo/química , Hipotálamo/efeitos dos fármacos , Injeções Intraventriculares/veterinária , Ocitocina/análogos & derivados , Ocitocina/fisiologia , Proteínas Proto-Oncogênicas c-fos/análise , RNA Mensageiro/análise
20.
Artigo em Inglês | MEDLINE | ID: mdl-30669302

RESUMO

High-temperature weather appears in high frequency, big strength, and long duration in the summer. It is therefore important to study the effects of high-temperature weather on sleep quality and appetite. Ten healthy college students were selected as subjects. The experiment conditions were divided by the daily maximum temperature into 28 °C, 32 °C, 36 °C, and 38 °C. The objective sleep quality was measured by an intelligent sleep monitoring belt, and the subjective sleep quality was measured by a questionnaire survey. The subjective appetites were assessed by a visual analog scale (VAS), and the objective appetites were assessed by the meal weight and the meal time. For sleep quality, the objective results indicated that the sleep quality at 32 °C was the best, followed by 28 °C, while the sleep quality at 36 °C and 38 °C was the worst. Significant effects were mainly reflected in sleep duration and shallow sleep. The subjective results showed that temperature had significant effects on sleep calmness, difficulty in falling asleep, sleep satisfaction, and sleep adequateness. For appetite, the VAS results indicated that high temperatures mainly led to a reduction of appetite at lunch time. The meal weights of lunch were larger than those of supper except for 28 °C, and the meal time of lunch and supper was longer than that of breakfast. The meal time of lunch was longer than that of supper except for 36 °C. This paper can provide a study method and reference data for the sleep quality and appetite of human in high-temperature weather.


Assuntos
Apetite/fisiologia , Temperatura Alta , Higiene do Sono/fisiologia , Adulto , Feminino , Humanos , Masculino , Refeições , Polissonografia , Inquéritos e Questionários
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