Abstracts - Association for Chemoreception Sciences

#9 INDUSTRY SYMPOSIUM:
TASTE AND SMELL IN TRANSLATION:
APPLICATIONS FROM BASIC RESEARCH
Insights from olfactory receptor screening
Joel Mainland
Monell Chemical Senses Center, Philadelphia PA 19104 USA
A major advances in the taste field in recent decades was the
identification of receptors that mediate taste. Expression of these
receptors in heterologous cell-based assays has allowed scientists
in both academia and industry to screen for novel taste agonists,
antagonists, and modifiers. Similar studies in olfactory receptors
have lagged behind the taste field due to the size of the receptor
family as well as difficulties in expressing the receptors in
heterologous cells. In this talk we will explore the current state of
the science in olfactory receptor screening, relationships between
odorant structure and odor quality, and the identification of
agonists, antagonists and modifiers for olfactory receptors.
#10 INDUSTRY SYMPOSIUM:
TASTE AND SMELL IN TRANSLATION:
APPLICATIONS FROM BASIC RESEARCH
Mechanisms of olfactory adaptation
Haiqing Zhao
Johns Hopkins University, Baltimore MD 21218 USA
Olfactory receptor cells exhibit reduced sensitivity upon
prolonged or repeated odor exposure––a phenomenon known as
adaptation. Adaptation at the cellular level is thought to underlie,
at least in part, the perceptual desensitization of an odor
over time. In vertebrates, several calcium-dependent feedback
mechanisms have been proposed to account for adaption of
olfactory receptor cells. Recent studies using molecular genetic
approaches that allow selective disruption of these calciumdependent
mechanisms have provide new insight into how
olfactory adaptation may occur.
#12 PRESIDENTIAL SYMPOSIUM:
GUT PEPTIDE INTERACTIONS BETWEEN
TASTE, FEEDING, AND REWARD
Bariatric surgery and appetite
Carel Le Roux
Experimental Pathology, UCD Conway Institute, School of Medicine
and Medical Science, University College Dublin, Ireland
A good model to investigate appetite reduction in humans and
rodents with associated major weight loss is bariatric surgery.
Gastric bypass, but not gastric banding caused increased
postprandial PYY and GLP-1 favouring enhanced satiety.
An early and exaggerated insulin response mediates improved
glycaemic control. The rodent model of bypass showed elevated
PYY, GLP-1 and gut hypertrophy compared with sham-operated
rats. Moreover, exogenous PYY reduced food intake while
blockade of endogenous PYY increased food intake.
A prospective follow-up human study of gastric bypass showed
progressively increasing PYY, enteroglucagon, and GLP-1
responses associated with enhanced satiety. Blocking these
responses in animal and human models leads to increased food
intake. Thus, following gastric bypass, a pleiotrophic endocrine
response may contribute to improved glycaemic control,
appetite reduction, and long-term lowering of body weight.
We have shown that changes occur in the sensory, reward
and physiological domains of taste that may mechanistically
contribute to the alterations in food preferences after gastric
bypass. The sustained nature of weight loss, reduced appetite
and shifts in food preferences may be explained by gut adaptation
and chronic hormone elevation.
#13 PRESIDENTIAL SYMPOSIUM:
GUT PEPTIDE INTERACTIONS BETWEEN
TASTE, FEEDING, AND REWARD
Common Mechanisms of Alimentary Chemosensation:
Implications for Taste, Ingestion and Glucose Homeostasis
Steven D. Munger 1,2
1
University of Maryland School of Medicine, Department of Anatomy
and Neurobiology Baltimore, MD, USA, 2 University of Maryland
School of Medicine, Department of Medicine Baltimore, MD, USA
The last two decades has seen a growing recognition that a
common molecular toolkit is employed along the length of the
alimentary canal to detect and respond to nutrients. For example,
many of the same proteins that are critical for recognizing sweet,
bitter and umami taste stimuli in the mouth, including T1R and
T2R taste receptors and the transduction proteins a-gustducin
and TRPM5, are found throughout the gastrointestinal (GI) tract
and associated organs. Similarly, taste buds express a number of
neuropeptides that are perhaps best understood in other systems
as endocrine factors that impact nutrient metabolism and/or
ingestive behaviors. A better understanding of the molecular
mechanisms that couple nutrient detection to peptide secretion in
gustatory and GI tissues could lead to the identification of new
pharmacological targets for impacting ingestion, satiety, nutrient
assimilation or glycemic control. I will discuss our recent studies
in rodents, including animals deficient in specific taste receptor
subunits or receiving Roux-en-Y gastric bypass, that provide
new insights into the mechanisms of nutrient response in the
mouth and gut and the role of these mechanisms in taste coding,
post-ingestive nutrient response, and the regulation of glucose
homeostasis. Acknowledgements: NIDCD (DC010110), Tate &
Lyle Americas, Ajinomoto Amino Acid Research Program
ORAL ABSTRACTS
Abstracts are printed as submitted by the author(s).
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