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Valerie B Duffy - One of the best experts on this subject based on the ideXlab platform.
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Revisiting sugar-fat mixtures: Sweetness and creaminess vary with phenotypic markers of oral sensation
2015Co-Authors: John E Hayes, Valerie B DuffyAbstract:Genetic variation in oral sensation presumably influences Ingestive Behaviors through sensations arising from foods and bev-erages. Here, we investigated the influence of taste phenotype [6-n-propylthiouracil (PROP) bitterness, fungiform papillae (FP) density] on sweet and creamy sensations from sugar/fat mixtures. Seventy-nine subjects (43 males) reported the sweetness and creaminess of water or milk (skim, whole, heavy cream) varying in sucrose (0–20%w/v) on the general LabeledMagnitude Scale. Sweetness grew with sucrose concentration and when shifting from water to milk mixtures—the growth was greatest for those tasting PROP as most bitter. At higher sucrose levels, increasing fat blunted the PROP–sweet relationship, whereas at lower levels, the relationship was effectively eliminated. Perceived sweetness of the mixture exceeded that predicted from the sum of com-ponents at low sucrose concentrations (especially for those tasting PROP most bitter) but fell below predicted at high concen-trations, irrespective of fat level. Creaminess increased greatly with fat level and somewhat with sucrose. Those tasting PROP most bitter perceived greater creaminess in the heavy cream across all sucrose levels. Perceived creaminess was somewhat lower than predicted, irrespective of PROP bitterness. The FP density generally showed similar effects as PROP on sweetness and cream-iness, (but to a lesser degree) and revealed potential taste–somatosensory interactions in weakly sweet stimuli. These data sup-port that taste phenotype affects the nature of enhancement or suppression of sweetness and creaminess in liquid fat/sugar mixtures. Taste phenotype effects on sweetness and creaminess likely involve differential taste, retronasal olfactory, and somato
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allelic variation in tas2r bitter receptor genes associates with variation in sensations from and Ingestive Behaviors toward common bitter beverages in adults
Chemical Senses, 2011Co-Authors: John E Hayes, Margaret R Wallace, Valerie S Knopik, Deborah M Herbstman, Linda M Bartoshuk, Valerie B DuffyAbstract:The 25 human bitter receptors and their respective genes (TAS2Rs) contain unusually high levels of allelic variation, which may influence response to bitter compounds in the food supply. Phenotypes based on the perceived bitterness of single bitter compounds were first linked to food preference over 50 years ago. The most studied phenotype is propylthiouracil bitterness, which is mediated primarily by the TAS2R38 gene and possibly others. In a laboratory-based study, we tested for associations between TAS2R variants and sensations, liking, or intake of bitter beverages among healthy adults who were primarily of European ancestry. A haploblock across TAS2R3, TAS2R4, and TAS2R5 explained some variability in the bitterness of espresso coffee. For grapefruit juice, variation at a TAS2R19 single nucleotide polymorphism (SNP) was associated with increased bitterness and decreased liking. An association between a TAS2R16 SNP and alcohol intake was identified, and the putative TAS2R38–alcohol relationship was confirmed, although these polymorphisms did not explain sensory or hedonic responses to sampled scotch whisky. In summary, TAS2R polymorphisms appear to influence the sensations, liking, or intake of common and nutritionally significant beverages. Studying perceptual and behavioral differences in vivo using real foods and beverages may potentially identify polymorphisms related to dietary behavior even in the absence of known ligands.
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revisiting sugar fat mixtures sweetness and creaminess vary with phenotypic markers of oral sensation
Chemical Senses, 2007Co-Authors: John E Hayes, Valerie B DuffyAbstract:Genetic variation in oral sensation presumably influences Ingestive Behaviors through sensations arising from foods and beverages. Here, we investigated the influence of taste phenotype [6-n-propylthiouracil (PROP) bitterness, fungiform papillae (FP) density] on sweet and creamy sensations from sugar/fat mixtures. Seventy-nine subjects (43 males) reported the sweetness and creaminess of water or milk (skim, whole, heavy cream) varying in sucrose (0–20% w/v) on the general Labeled Magnitude Scale. Sweetness grew with sucrose concentration and when shifting from water to milk mixtures—the growth was greatest for those tasting PROP as most bitter. At higher sucrose levels, increasing fat blunted the PROP–sweet relationship, whereas at lower levels, the relationship was effectively eliminated. Perceived sweetness of the mixture exceeded that predicted from the sum of components at low sucrose concentrations (especially for those tasting PROP most bitter) but fell below predicted at high concentrations, irrespective of fat level. Creaminess increased greatly with fat level and somewhat with sucrose. Those tasting PROP most bitter perceived greater creaminess in the heavy cream across all sucrose levels. Perceived creaminess was somewhat lower than predicted, irrespective of PROP bitterness. The FP density generally showed similar effects as PROP on sweetness and creaminess, (but to a lesser degree) and revealed potential taste–somatosensory interactions in weakly sweet stimuli. These data support that taste phenotype affects the nature of enhancement or suppression of sweetness and creaminess in liquid fat/sugar mixtures. Taste phenotype effects on sweetness and creaminess likely involve differential taste, retronasal olfactory, and somatosensory contributions to these perceptual experiences.
John E Hayes - One of the best experts on this subject based on the ideXlab platform.
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Revisiting sugar-fat mixtures: Sweetness and creaminess vary with phenotypic markers of oral sensation
2015Co-Authors: John E Hayes, Valerie B DuffyAbstract:Genetic variation in oral sensation presumably influences Ingestive Behaviors through sensations arising from foods and bev-erages. Here, we investigated the influence of taste phenotype [6-n-propylthiouracil (PROP) bitterness, fungiform papillae (FP) density] on sweet and creamy sensations from sugar/fat mixtures. Seventy-nine subjects (43 males) reported the sweetness and creaminess of water or milk (skim, whole, heavy cream) varying in sucrose (0–20%w/v) on the general LabeledMagnitude Scale. Sweetness grew with sucrose concentration and when shifting from water to milk mixtures—the growth was greatest for those tasting PROP as most bitter. At higher sucrose levels, increasing fat blunted the PROP–sweet relationship, whereas at lower levels, the relationship was effectively eliminated. Perceived sweetness of the mixture exceeded that predicted from the sum of com-ponents at low sucrose concentrations (especially for those tasting PROP most bitter) but fell below predicted at high concen-trations, irrespective of fat level. Creaminess increased greatly with fat level and somewhat with sucrose. Those tasting PROP most bitter perceived greater creaminess in the heavy cream across all sucrose levels. Perceived creaminess was somewhat lower than predicted, irrespective of PROP bitterness. The FP density generally showed similar effects as PROP on sweetness and cream-iness, (but to a lesser degree) and revealed potential taste–somatosensory interactions in weakly sweet stimuli. These data sup-port that taste phenotype affects the nature of enhancement or suppression of sweetness and creaminess in liquid fat/sugar mixtures. Taste phenotype effects on sweetness and creaminess likely involve differential taste, retronasal olfactory, and somato
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allelic variation in tas2r bitter receptor genes associates with variation in sensations from and Ingestive Behaviors toward common bitter beverages in adults
Chemical Senses, 2011Co-Authors: John E Hayes, Margaret R Wallace, Valerie S Knopik, Deborah M Herbstman, Linda M Bartoshuk, Valerie B DuffyAbstract:The 25 human bitter receptors and their respective genes (TAS2Rs) contain unusually high levels of allelic variation, which may influence response to bitter compounds in the food supply. Phenotypes based on the perceived bitterness of single bitter compounds were first linked to food preference over 50 years ago. The most studied phenotype is propylthiouracil bitterness, which is mediated primarily by the TAS2R38 gene and possibly others. In a laboratory-based study, we tested for associations between TAS2R variants and sensations, liking, or intake of bitter beverages among healthy adults who were primarily of European ancestry. A haploblock across TAS2R3, TAS2R4, and TAS2R5 explained some variability in the bitterness of espresso coffee. For grapefruit juice, variation at a TAS2R19 single nucleotide polymorphism (SNP) was associated with increased bitterness and decreased liking. An association between a TAS2R16 SNP and alcohol intake was identified, and the putative TAS2R38–alcohol relationship was confirmed, although these polymorphisms did not explain sensory or hedonic responses to sampled scotch whisky. In summary, TAS2R polymorphisms appear to influence the sensations, liking, or intake of common and nutritionally significant beverages. Studying perceptual and behavioral differences in vivo using real foods and beverages may potentially identify polymorphisms related to dietary behavior even in the absence of known ligands.
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revisiting sugar fat mixtures sweetness and creaminess vary with phenotypic markers of oral sensation
Chemical Senses, 2007Co-Authors: John E Hayes, Valerie B DuffyAbstract:Genetic variation in oral sensation presumably influences Ingestive Behaviors through sensations arising from foods and beverages. Here, we investigated the influence of taste phenotype [6-n-propylthiouracil (PROP) bitterness, fungiform papillae (FP) density] on sweet and creamy sensations from sugar/fat mixtures. Seventy-nine subjects (43 males) reported the sweetness and creaminess of water or milk (skim, whole, heavy cream) varying in sucrose (0–20% w/v) on the general Labeled Magnitude Scale. Sweetness grew with sucrose concentration and when shifting from water to milk mixtures—the growth was greatest for those tasting PROP as most bitter. At higher sucrose levels, increasing fat blunted the PROP–sweet relationship, whereas at lower levels, the relationship was effectively eliminated. Perceived sweetness of the mixture exceeded that predicted from the sum of components at low sucrose concentrations (especially for those tasting PROP most bitter) but fell below predicted at high concentrations, irrespective of fat level. Creaminess increased greatly with fat level and somewhat with sucrose. Those tasting PROP most bitter perceived greater creaminess in the heavy cream across all sucrose levels. Perceived creaminess was somewhat lower than predicted, irrespective of PROP bitterness. The FP density generally showed similar effects as PROP on sweetness and creaminess, (but to a lesser degree) and revealed potential taste–somatosensory interactions in weakly sweet stimuli. These data support that taste phenotype affects the nature of enhancement or suppression of sweetness and creaminess in liquid fat/sugar mixtures. Taste phenotype effects on sweetness and creaminess likely involve differential taste, retronasal olfactory, and somatosensory contributions to these perceptual experiences.
Timothy J Bartness - One of the best experts on this subject based on the ideXlab platform.
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Ingestive Behaviors IN SIBERIAN HAMSTERS (PHODOPUS SUNGORUS) by
2014Co-Authors: Hamsters Sungorus, Megan J Dailey, Under Direction, Timothy J BartnessAbstract:During the past few decades, obesity has risen significantly in the United States with recent estimates showing that 65 % of Americans are overweight and 30 % are obese. This increase is a major cause for concern because obesity is linked to many secondary health consequences that include type II diabetes, heart disease, and cancer. Current approaches to the obesity problem primarily have focused on controls of food intake and have been largely unsuccessful. Food, however, almost always has to be acquired (foraging) and frequently is stored for later consumption (hoarding). Therefore, a more comprehensive approach that includes studying the underlying mechanisms in human foraging and food hoarding Behaviors could provide an additional target for pharmaceutical or behavioral manipulations in the treatment and possibly prevention of obesity. Neuropeptide Y (NPY) is a particular peptide that provides a potent orexigenic drive to alter foraging, food hoarding (appetitive Ingestive Behaviors) and food intake (consummatoryIngestive Behaviors) in variety of species. NPY is predominantly produced in the arcuate nucleus of the hypothalamus (ARC) and has extensive efferent projections throughout the brain. Two target nuclei of ARC-NPY, the paraventricular nucleus of the hypothalamus (PVH) an
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Inhibition of ghrelin O-acyltransferase attenuates food deprivation-induced increases in Ingestive behavior.
Hormones and behavior, 2013Co-Authors: Brett J. W. Teubner, John T. Garretson, Yousang Hwang, Philip A. Cole, Timothy J BartnessAbstract:Ghrelin is an orexigenic hormone produced by the stomach in direct proportion to the time since the last meal and has therefore been called a 'hunger signal'. The octanoylation of ghrelin is critical for its orexigenic functions and is dependent upon ghrelin O-acyltransferase (GOAT) catalyzation. The GOAT inhibitor, GO-CoA-Tat, decreases the circulating concentrations of octanoylated ghrelin and attenuates weight gain on a high fat diet in mice. Unlike rats and mice, Siberian hamsters and humans do not increase food intake after food deprivation, but increase food hoarding after food deprivation. In Siberian hamsters, exogenous ghrelin increases Ingestive Behaviors similarly to 48-56 h food deprivation. Therefore, we tested the necessity of increased ghrelin in food-deprived Siberian hamsters to stimulate Ingestive Behaviors. To do so we used our simulated natural housing system that allows hamsters to forage for and hoard food. Animals were given an injection of GO-CoA-Tat (i.p., 11 μmol/kg) every 6h because that is the duration of its effective inhibition of octanoylated ghrelin concentrations during a 48 h food deprivation. We found that GO-CoA-Tat attenuated food foraging (0-1h), food intake (0-1 and 2-4h), and food hoarding (0-1h and 2 and 3 days) post-refeeding compared with saline treated animals. This suggests that increased octanoylated ghrelin concentrations play a role in the food deprivation-induced increases in Ingestive behavior. Therefore, ghrelin is a critical aspect of the multi-faceted mechanisms that stimulate Ingestive Behaviors, and might be a critical point for a successful clinical intervention scheme in humans.
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appetitive and consummatory Ingestive Behaviors stimulated by pvh and perifornical area npy injections
American Journal of Physiology-regulatory Integrative and Comparative Physiology, 2009Co-Authors: Megan J Dailey, Timothy J BartnessAbstract:Food is acquired (obtained by foraging) and frequently stored (hoarded) across animal taxa, including humans, but the physiological mechanisms underlying these Behaviors are virtually unknown. We found that peptides that stimulate food intake in rats stimulate food foraging and/or hoarding more than intake in Siberian hamsters. Neuropeptide Y (NPY) is a potent orexigenic peptide that increases food foraging and hoarding (appetitive behavior) and food intake (consummatory behavior). Given that NPY injections into the hypothalamic paraventricular nucleus (PVH) or perifornical area (PFA) increase food intake by rats, it is possible that these injections may stimulate food foraging or hoarding by Siberian hamsters. We also tested whether antagonism of the NPY Y1 receptor (Y1-R), the agonism of which stimulates hoarding, would inhibit post-food-deprivation increases in foraging and hoarding. We injected one of three doses of NPY or vehicle into the PVH or PFA of animals housed in a simulated foraging-hoarding housing system and measured these Behaviors at 1, 2, 4, and 24 h. A subset of animals was subsequently food deprived and then given PVH or PFA Y1-R antagonist microinjections before they were refed. NPY PVH microinjections decreased foraging but increased hoarding and food intake, whereas NPY PFA microinjections increased all three Behaviors, but the greatest increase was in hoarding. Y1-R antagonist inhibited post-food-deprivation increases in hoarding when injected into the PVH and PFA and inhibited foraging when injected into the PFA. These results support the view that NPY is involved in appetitive and consummatory Ingestive Behaviors, but each may be controlled by different brain areas and/or NPY receptor subtypes.
Megan J Dailey - One of the best experts on this subject based on the ideXlab platform.
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Ingestive Behaviors IN SIBERIAN HAMSTERS (PHODOPUS SUNGORUS) by
2014Co-Authors: Hamsters Sungorus, Megan J Dailey, Under Direction, Timothy J BartnessAbstract:During the past few decades, obesity has risen significantly in the United States with recent estimates showing that 65 % of Americans are overweight and 30 % are obese. This increase is a major cause for concern because obesity is linked to many secondary health consequences that include type II diabetes, heart disease, and cancer. Current approaches to the obesity problem primarily have focused on controls of food intake and have been largely unsuccessful. Food, however, almost always has to be acquired (foraging) and frequently is stored for later consumption (hoarding). Therefore, a more comprehensive approach that includes studying the underlying mechanisms in human foraging and food hoarding Behaviors could provide an additional target for pharmaceutical or behavioral manipulations in the treatment and possibly prevention of obesity. Neuropeptide Y (NPY) is a particular peptide that provides a potent orexigenic drive to alter foraging, food hoarding (appetitive Ingestive Behaviors) and food intake (consummatoryIngestive Behaviors) in variety of species. NPY is predominantly produced in the arcuate nucleus of the hypothalamus (ARC) and has extensive efferent projections throughout the brain. Two target nuclei of ARC-NPY, the paraventricular nucleus of the hypothalamus (PVH) an
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appetitive and consummatory Ingestive Behaviors stimulated by pvh and perifornical area npy injections
American Journal of Physiology-regulatory Integrative and Comparative Physiology, 2009Co-Authors: Megan J Dailey, Timothy J BartnessAbstract:Food is acquired (obtained by foraging) and frequently stored (hoarded) across animal taxa, including humans, but the physiological mechanisms underlying these Behaviors are virtually unknown. We found that peptides that stimulate food intake in rats stimulate food foraging and/or hoarding more than intake in Siberian hamsters. Neuropeptide Y (NPY) is a potent orexigenic peptide that increases food foraging and hoarding (appetitive behavior) and food intake (consummatory behavior). Given that NPY injections into the hypothalamic paraventricular nucleus (PVH) or perifornical area (PFA) increase food intake by rats, it is possible that these injections may stimulate food foraging or hoarding by Siberian hamsters. We also tested whether antagonism of the NPY Y1 receptor (Y1-R), the agonism of which stimulates hoarding, would inhibit post-food-deprivation increases in foraging and hoarding. We injected one of three doses of NPY or vehicle into the PVH or PFA of animals housed in a simulated foraging-hoarding housing system and measured these Behaviors at 1, 2, 4, and 24 h. A subset of animals was subsequently food deprived and then given PVH or PFA Y1-R antagonist microinjections before they were refed. NPY PVH microinjections decreased foraging but increased hoarding and food intake, whereas NPY PFA microinjections increased all three Behaviors, but the greatest increase was in hoarding. Y1-R antagonist inhibited post-food-deprivation increases in hoarding when injected into the PVH and PFA and inhibited foraging when injected into the PFA. These results support the view that NPY is involved in appetitive and consummatory Ingestive Behaviors, but each may be controlled by different brain areas and/or NPY receptor subtypes.
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Neuropeptide Y-Mediated Control of Appetitive and Consummatory Ingestive Behaviors in Siberian Hamsters (Phodopus sungorus)
2007Co-Authors: Megan J DaileyAbstract:During the past few decades, obesity has risen significantly in the United States with recent estimates showing that 65% of Americans are overweight and 30% are obese. This increase is a major cause for concern because obesity is linked to many secondary health consequences that include type II diabetes, heart disease, and cancer. Current approaches to the obesity problem primarily have focused on controls of food intake and have been largely unsuccessful. Food, however, almost always has to be acquired (foraging) and frequently is stored for later consumption (hoarding). Therefore, a more comprehensive approach that includes studying the underlying mechanisms in human foraging and food hoarding Behaviors could provide an additional target for pharmaceutical or behavioral manipulations in the treatment and possibly prevention of obesity. Neuropeptide Y (NPY) is a particular peptide that provides a potent orexigenic drive to alter foraging, food hoarding (appetitive Ingestive Behaviors) and food intake (consummatory Ingestive Behaviors) in variety of species. NPY is predominantly produced in the arcuate nucleus of the hypothalamus (ARC) and has extensive efferent projections throughout the brain. Two target nuclei of ARC-NPY, the paraventricular nucleus of the hypothalamus (PVH) and perifornical area (PFA), have been shown to mediate the effect of NPY on food intake in laboratory rats and mice, but nothing is known about the effect of ARC-NPY on foraging and food hoarding. In addition, the action of specific NPY receptor subtypes within these two nuclei for these Behaviors is unknown. Even though ARC-NPY is one of the main sources of input into the PVH and PFA, it is not known if this NPY fiber projection mediates alterations in appetitive and consummatory Ingestive Behaviors. Therefore, the purpose of this dissertation is to test 1) if NPY within the PVH or PFA controls appetitive, as well as, consummatory Ingestive Behaviors, 2) if NPY Y1 receptors within the PVH or PFA differentially control appetitive or consummatory Ingestive Behaviors, and 3) if NPY from the ARC is necessary for the control of appetitive and consummatory Ingestive Behaviors. INDEX WORDS: Obesity, Appetitive, Consummatory, Ingestive Behaviors, Food Hoarding, Neuropeptide Y (NPY) NEUROPEPTIDE Y-MEDIATED CONTROL OF APPETITIVE AND CONSUMMATORY Ingestive Behaviors IN SIBERIAN HAMSTERS (PHODOPUS SUNGORUS)
Francis W. Flynn - One of the best experts on this subject based on the ideXlab platform.
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Applications of taste reactivity to the study of the neural-hormonal controls of Ingestive behavior
Neuroscience and biobehavioral reviews, 1995Co-Authors: Francis W. FlynnAbstract:Taste plays a central role in guiding Ingestive behavior and the encoding of taste is affected by manipulations that influence Ingestive behavior. In this article, the use of the taste reactivity test to provide a behavioral assessment of how changes in the oral reinforcing properties of a taste may initiate or sustain Ingestive Behaviors in several contexts are discussed. The affects of the animal's sex, sodium deficiency, exogenous bombesin administration, and the role of central gustatory lesions in mediating taste reactivity responses are discussed. Findings indicate that an enhancement of Ingestive taste reactivity responses correlate with an increased preference and intake of taste stimuli for some, but not all situations. Such situations include the bombesin-like peptides that reduce sucrose and sodium chloride intake without influencing taste reactivity responses. Conversely, female rats, compared to males, show an elevated intake and preference for a range of NaCl concentrations and a greater number of Ingestive taste reactivity responses to some, but not all of the preferred concentrations. Such mismatches of taste reactivity and intake measures shift attention to the contribution of nongustatory factors (trigeminal, visceral) in the control of intake.
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Central gustatory lesions: II. Effects on sodium appetite, taste aversion learning, and feeding Behaviors.
Behavioral Neuroscience, 1991Co-Authors: Francis W. Flynn, Harvey J. Grill, Jay Schulkin, Ralph NorgrenAbstract:Intake and taste reactivity tests were used to determine the effects of bilateral lesions of the gustatory portions of the nucleus of the solitary tract (NST), the parabrachial nucleus (PBN), and the ventral posteromedial nucleus of the thalamus (VPMpc) on several complex Ingestive Behaviors. In the 1st experiment, lesions of the PBN and the NST blocked, and VPMpc lesions impaired, the behavioral expression of salt appetite. In the 2nd experiment, alanine was paired with injections of LiCl. Control rats as well as rats with NST and VPMpc lesions acquired the taste aversion, but rats with PBN lesions did not. In the 3rd experiment, all animals increased their food intake after injections of 2 U/kg insulin and 250 mg/kg 2-deoxy-D-glucose, and their food intake was suppressed after nutritive stomach loads.