Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020175 (hunger)
 5,670 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The hypothesis that prandial increases in circulating pancreatic glucagon initiates an important peripheral satiety signal is reviewed. Glucagon administration at the beginning of meals reduces the size of test meals in animals and humans and reduces the size of spontaneous meals in rats. Exogenous glucagon may also interact synergistically with cholecystokinin to inhibit feeding. These appear to be satiety effects because they are behaviorally specific in rats and subjectively specific in humans. Glucagon's pharmacological satiety effect is complemented by compelling evidence for a necessary contribution of endogenous glucagon to the control of meal size: administration of glucagon antibodies increases both test and spontaneous meal size in rats. Under many, but not all, conditions exogenous glucagon's satiety effect appears to originate in the liver and to be relayed to the brain via hepatic vagal afferents. Analysis of the central processing of this signal, however, has barely begun. How glucagon changes are transduced into neural afferent signals also remains an open question. The only hypothesis that has been extensively tested is that stimulation of hepatic glucose production initiates the satiety signal, but this is neither convincingly supported nor clearly rejected by currently available data. It is also not yet clear whether glucagon contributes to some forms of obesity or has potential use as a therapeutic tool in the control of eating disorders. Of the several proposed controls of hunger and satiety, glucagon appears to be one of the most likely to be physiologically relevant. This encourages further analysis of its behavioral characteristics, its neural mechanisms, and its clinical potential.
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PMID:Pancreatic glucagon signals postprandial satiety. 223 10

Glucagon-like peptide-1-(7-36) amide (GLP-1) is an incretin hormone of the enteroinsular axis. Recent experimental evidence in animals and healthy subjects suggests that GLP-1 has a role in controlling appetite and energy intake in humans. We have therefore examined in a double-blind, placebo-controlled, crossover study in 12 patients with diabetes type 2 the effect of intravenously infused GLP-1 on appetite sensations and energy intake. On 2 days, either saline or GLP-1 (1.5 pmol. kg-1. min-1) was given throughout the experiment. Visual analog scales were used to assess appetite sensations; furthermore, food and fluid intake of a test meal were recorded, and blood was sampled for analysis of plasma glucose and hormone levels. GLP-1 infusion enhanced satiety and fullness compared with placebo (P = 0.028 for fullness and P = 0.026 for hunger feelings). Energy intake was reduced by 27% by GLP-1 (P = 0.034) compared with saline. The results demonstrate a marked effect of GLP-1 on appetite by showing enhanced satiety and reduced energy intake in patients with diabetes type 2.
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PMID:Glucagon-like peptide-1 promotes satiety and reduces food intake in patients with diabetes mellitus type 2. 1023 49

Seven studies have now been published pertaining to the acute effect of iv administration of glucagon-like peptide-1 (7-36) amide on ad libitum energy intake. In four of these studies energy intake was significantly reduced following the glucagon-like peptide-1 infusion compared with saline. In the remaining studies, no significant effect of glucagon-like peptide-1 could be shown. Lack of statistical power or low glucagon-like peptide-1 infusion rate may explain these conflicting results. Our aim was to examine the effect of glucagon-like peptide-1 on subsequent energy intake using a data set composed of subject data from previous studies and from two as yet unpublished studies. Secondly, we investigated whether the effect on energy intake is dose dependent and differs between lean and overweight subjects. Raw subject data on body mass index and ad libitum energy intake were collected into a common data set (n = 115), together with study characteristics such as infusion rate, duration of infusion, etc. From four studies with comparable protocol the following subject data were included if available: plasma concentrations of glucagon-like peptide-1, subjective appetite measures, well-being, and gastric emptying rate of a meal served at the start of the glucagon-like peptide-1 infusion. Energy intake was reduced by 727 kJ (95% confidence interval, 548-908 kJ) or 11.7% during glucagon-like peptide-1 infusion. Although the absolute reduction in energy intake was higher in lean (863 kJ) (634-1091 kJ) compared with overweight subjects (487 kJ) (209-764 kJ) (P = 0.05), the relative reduction did not differ between the two groups (13.2% and 9.3%, respectively). Stepwise regression analysis showed that the glucagon-like peptide-1 infusion rate was the only independent predictor of the reduction in energy intake during glucagon-like peptide-1 (7-36) amide infusion (r = 0.4, P < 0.001). Differences in mean plasma glucagon-like peptide-1 concentration on the glucagon-like peptide-1 and placebo day (n = 43) were related to differences in feelings of prospective consumption (r = 0.40, P < 0.01), fullness (r = 0.38, P < 0.05), and hunger (r = 0.26, P = 0.09), but not to differences in ad libitum energy intake. Gastric emptying rate was significantly lower during glucagon-like peptide-1 infusion compared with saline. Finally, well-being was not influenced by the glucagon-like peptide-1 infusion. Glucagon-like peptide-1 infusion reduces energy intake dose dependently in both lean and overweight subjects. A reduced gastric emptying rate may contribute to the increased satiety induced by glucagon-like peptide-1.
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PMID:A meta-analysis of the effect of glucagon-like peptide-1 (7-36) amide on ad libitum energy intake in humans. 1154 80

Glucagon-like peptide-1 (GLP-1) relaxes the stomach during fasting but decreases hunger and food consumption and retards gastric emptying. The interrelationships between volume, emptying, and postprandial symptoms in response to GLP-1 are unclear. We performed, in healthy human volunteers, a placebo-controlled study of the effects of intravenous GLP-1 on gastric volume using (99m)Tc-single photon emission computed tomography imaging, gastric emptying of a nutrient liquid meal (Ensure) using scintigraphy, maximum tolerated volume (MTV) of Ensure, and postprandial symptoms 30 min after MTV. The role of vagal cholinergic function in the effects of GLP-1 was assessed by human pancreatic polypeptide (HPP) response to the Ensure meal. GLP-1 increased fasting and postprandial gastric volumes and retarded gastric emptying; MTV and postprandial symptoms were not different compared with controls. Effects on postprandial gastric function were associated with reduced postprandial HPP levels. GLP-1 does not induce postprandial symptoms despite significant inhibition of gastric emptying and vagal function; this may be partly explained by the increase in postprandial gastric volume.
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PMID:Effect of GLP-1 on gastric volume, emptying, maximum volume ingested, and postprandial symptoms in humans. 1184 92

Ghrelin is a novel enteric hormone that stimulates growth hormone (GH), ACTH, and epinephrine; augments plasma glucose; and increases food intake by inducing the feeling of hunger. These characteristics make ghrelin a potential counterregulatory hormone. At present, it is not known whether ghrelin increases in response to insulin-induced hypoglycemia. To answer this question, we compared plasma ghrelin concentrations after a short-term insulin infusion that was allowed or not (euglycemic clamp) to cause hypoglycemia (2.7 +/- 0.2 mmol/l at 30 min) in five healthy volunteers. In both studies, plasma ghrelin concentrations decreased (P < 0.01) after insulin infusion (hypoglycemia by 14%, euglycemia by 22%), reached a nadir at 30 min, and returned to baseline at 60 min, without differences between the hypoglycemia and the euglycemia studies. Glucagon, cortisol, and GH increased in response to hypoglycemia despite the decreased ghrelin. There was a strong correlation (R(2) = 0.91, P < 0.002) between the insulin sensitivity of the subjects and the percentage suppression of ghrelin from baseline. These data demonstrate that ghrelin is not required for the hormonal defenses against insulin-induced hypoglycemia and that insulin can suppress ghrelin levels in healthy humans. These results raise the possibility that postprandial hyperinsulinemia is responsible for the reduction of plasma ghrelin that occurs during meal intake.
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PMID:Ghrelin is not necessary for adequate hormonal counterregulation of insulin-induced hypoglycemia. 1235 26

Glucagon-like peptide-1 (GLP-1) and glucagon-like peptide-2 (GLP-2) are secreted in parallel to the circulation after a meal. Intravenous (IV) GLP-1 has an inhibitory effect on gastric emptying, hunger and food intake in man. In rodents, central administration of GLP-2 increases satiety similar to GLP-1. The aim of the present study was to assess the effect of IV administered GLP-2 on gastric emptying and feelings of hunger in human volunteers. In eight (five men) healthy subjects (age 31.1+/-2.9 years and BMI 24.1+/-1.0 kg m(-2)), scintigraphic solid gastric emptying, hunger ratings (VAS) and plasma concentrations of GLP-2 were studied during infusion of saline or GLP-2 (0.75 and 2.25 pmol kg(-1) min(-1)) for a total of 180 min. Concentrations of GLP-2 were elevated to a maximum of 50 and 110 pmol l(-1) for 0.75 and 2.25 pmol kg(-1) min(-1) infusion of GLP-2, respectively. There was no effect of GLP-2 on either the lag phase (29.5+/-4.4, 26.0+/-5.2 and 21.2+/-3.6 min for saline, GLP-2 0.75 or 2.25 pmol kg(-1) min(-1), respectively) or the half emptying time (84.5+/-6.1, 89.5+/-17.8 and 85.0+/-7.0 min for saline, GLP-2 0.75 or 2.25 pmol kg(-1) min(-1), respectively). The change in hunger rating after the meal to 180 min was also unaffected by infusion of GLP-2. GLP-2 does not seem to mediate the ileal brake mechanism.
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PMID:Peripheral administration of GLP-2 to humans has no effect on gastric emptying or satiety. 1459 11

The discovery of the adiposity signal leptin a decade ago revolutionised our understanding of the hypothalamic mechanisms underpinning the central control of ingestive behaviour. Subsequently, the structure and function of various hypothalamic peptide systems (Neuropeptide Y (NPY), Orexins, Melanocortins, Cocaine and Amphetamine Regulating Transcript (CART), Galanin/Galanin Like Peptides (GALP) and endocannabinoids) have been characterised in detail in rodent models. The therapeutic benefit of targeting these systems remains to be discovered. More is becoming known about the pharmacological potential of peripheral, meal-induced, episodic endogenous peptides. Hormones such as Cholecystokinin (CCK), Gastrin Releasing Peptides (GRP), Glucagon-Like Peptide I (GLP-1) Enterostatin, Amylin, Peptide YY (PYY) and Ghrelin are released prior to, during and/or after a meal, controlling intake and subjective feelings of appetite (hunger and satiety). In addition, there is an expanding body of literature detailing the effects of a wide variety of drugs on human appetite and food intake. Some of these drugs act upon CNS monoamine systems such as Serotonin (5-HT). Dopamine (DA) and Noradrenaline (NA), have long been implicated in appetite regulation. Detailed examination of both the effect of agonising endogenous gut peptide systems and the effect of various monoaminergic drugs on the expression of human appetite can provide a greater understanding of mechanisms underpinning normal appetite regulation. However, such an understanding must be based on knowledge of the effect of the treatment on meal size, eating rate, meal pattern, food choice and the subjective experience of appetite flux (hunger and satiety), and notjust food intake.
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PMID:The pharmacology of human appetite expression. 1505 9

Glucagon-like peptide-1 (GLP-1) and CCK-33 were intravenously infused alone or in combination into normal weight men for 60 min before they were served a lunch of ham sandwiches, chocolate mousse, and orange juice. Infusion of GLP-1 (dose: 0.9 pmol x kg(-1) x min(-1)) or CCK-33 (dose: 0.2 pmol x kg(-1) x min(-1)) each reduced calorie intake of the test meal. However, simultaneous infusion of these peptide doses reduced calorie intake less than the sum of the peptides' individual effects. Infusions of the same doses of GLP-1 plus CCK-33 had neither individual nor interactive effects on meal size or calorie consumption. The combination of GLP-1 plus CCK-33 induced, however, a significant reduction in hunger feelings in the premeal period (P = 0.036 vs. all other treatments). In summary, intravenous infusion of near physiological doses of CCK-33 and GLP-1 produced specific inhibitions of hunger feeling in men; the simultaneous infusion resulted in an infra-additive reduction in calorie consumption, rejecting thereby the hypothesis that the two peptides exert a positive synergistic effect on food intake compared with the effects observed with infusion of individual peptides. In conclusion, CCK and GLP-1 are meal-related satiety signals that are released from the gastrointestinal tract during food intake.
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PMID:Interaction between GLP-1 and CCK-33 in inhibiting food intake and appetite in men. 1510 67

In normal individuals hypoglycemic counterregulation is a multifactorial, redundant process that involves reduction of insulin secretion, increasing glucagon secretion, adrenergic activation, and increased growth hormone and cortisol secretion. Metabolically, these lead to increased glucose production, initially through glycogenolysis and later through gluconeogenesis, decreased muscle glucose oxidation and storage and increased release and use of alternative fuels, primarily free fatty acids. They also lead to hypoglycemic symptoms and hunger which increase food intake. These systems are designed to provide as much glucose as possible for brain glucose use. In patients with type 1 diabetes there are multiple impairments of these responses. Insulin does not decrease. Glucagon secretion is decreased or absent. Recovery from hypoglycemia is therefore dependent on the adrenergic response. Hypoglycemia increases plasma levels of both epinephrine and norepinephrine. These catechols are released primarily from the adrenal medulla. However, it is well documented that hypoglycemic increases muscle sympathetic nerve activity, and that both alpha and beta adrenergic activity increase. Increased beta-activity increases free fatty acid release which increase glucose production and decrease glucose utilization. The increased alpha-adrenergic activity's primary role is to counteract beta-adrenergic vasodilation. It may also reduce neurogenic and neuroglycopenic symptoms. Lastly, there is evidence that both cardiac and adrenergic sensitivity are altered in type 1 diabetes. It is hoped that this information can be used in the future to help develop ways to protect patients with type 1 diabetes from hypoglycemia and its adverse effects.
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PMID:Sympathetic mechanisms of hypoglycemic counterregulation. 1822 Jun 70

Dietary protein plays a role in body weight regulation, partly because of its effects on appetite. The objective was to compare the effects of high or normal casein-, soy-, or whey-protein breakfasts on appetite, specific hormones, amino acid responses and subsequent energy intake. Twenty-five healthy subjects (mean+/-SEMBMI:23.9+/-0.3 kg/m2; age:22+/-1 years) received standardized breakfasts: custards with either casein-, soy, or whey-protein with either 10/55/35 (normal) or 25/55/20 (high)En% protein/carbohydrate/fat in a randomized, single-blind design. Appetite profile (Visual Analogue Scales) and amino acid concentrations were determined for 4 h whereas plasma glucose, insulin, active Glucagon-like Peptide 1 (GLP-1), and active ghrelin concentrations were determined for 3 h; the sensitive moment for lunch was determined. Subjects returned for a second set of experiments and received the same breakfasts, ad lib lunch was offered 180 min later; energy intake (EI) was assessed. At 10En%, whey decreased hunger more than casein or soy (p <0.05), coinciding with higher leucine, lysine, tryptophan, isoleucine, and threonine responses (p<0.05). At 25En% there were no differences in appetite ratings. Whey triggered the strongest responses in concentrations of active GLP-1 (p<0.05) and insulin (p<0.05) compared with casein and/or soy. There were no differences in EI. In conclusion, differences in appetite ratings between different proteins appeared at a normal concentration; at 10En% whey-protein decreased hunger more than casein- or soy-protein. At 25En% whey-protein triggered stronger responses in hormone concentrations than casein- or soy-protein. The results suggest that a difference in appetite ratings between types of protein appears when certain amino acids are above and below particular threshold values.
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PMID:Dose-dependent satiating effect of whey relative to casein or soy. 1938 22


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