Gastric sensorimotor functions and hormone profile in normal weight, overweight, and obese people.
OBJECTIVE
Peptide YY (PYY) levels are reported to be decreased in obesity. The relation between gastric functions, satiation, and gut hormones in obesity is incompletely understood. The aim of this study was to compare gastric volumes, emptying, maximum tolerated volumes, postchallenge symptoms, and selected gut hormones in normal, overweight, or obese healthy volunteers.


METHODS
In 73 nonbulimic normal, overweight, or obese participants weighing less than 137 kg, we measured gastric emptying of solids and liquids by scintigraphy (gastric emptying half-time [GE t(1/2)]); gastric volumes by single-photon emission computed tomography; maximum tolerated volumes and symptoms by satiation test; and plasma leptin, ghrelin, insulin, glucagon-like peptide 1, and PYY levels. Groups were compared using 1-way analysis of covariance adjusted for sex. Univariate associations among measured responses were assessed using Spearman correlations. Multiple linear regression models, adjusting for weight and sex, assessed the independent ability of gastric functions and hormones to predict satiation volume.


RESULTS
Obese and overweight subjects had significantly lower postprandial gastric volumes, higher fasting and postprandial insulin and leptin levels, and lower fasting ghrelin and lower postprandial reduction in ghrelin levels. PYY levels were not different in obese or overweight subjects compared with controls. The GE t(1/2) was correlated inversely with postprandial PYY; increased body weight was associated with faster GE t(1/2) of solids (r(s) = 0.33, P = .005) and liquids (r(s) = 0.24, P = .04). Postprandial changes in gastric volume and PYY were independent predictors of satiation (both P = .01).


CONCLUSIONS
Overweight or obesity are associated with lower postprandial gastric volumes and normal PYY levels. Gastric emptying influences postprandial PYY levels. Postprandial PYY and gastric volume independently predict satiation volume in nonbulimic people across a wide body mass index range.
Vazquez Roque
Maria I
MI
Clinical Enteric Neuroscience Translational and Epidemiological Research Program, Mayo Clinic College of Medicine, Rochester, Minnesota 55905, USA.
Camilleri
Michael
M
Stephens
Debra A
DA
Jensen
Michael D
MD
Burton
Duane D
DD
Baxter
Kari L
KL
Zinsmeister
Alan R
AR
D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D005746:Gastric Emptying / Q000502:physiology*; D005768:Gastrointestinal Hormones / Q000097:blood*; D054439:Ghrelin; D052216:Glucagon-Like Peptide 1 / Q000097:blood; D006801:Humans; D007328:Insulin / Q000097:blood; D020738:Leptin / Q000097:blood; D008297:Male; D008875:Middle Aged; D009046:Motor Neurons / Q000502:physiology; D009475:Neurons, Afferent / Q000502:physiology; D009765:Obesity / Q000097:blood* / Q000473:pathology / Q000503:physiopathology*; D050177:Overweight / Q000502:physiology*; D036361:Peptide Hormones / Q000097:blood; D019894:Peptide YY / Q000097:blood*; D012044:Regression Analysis; D012527:Satiation / Q000502:physiology; D013270:Stomach / Q000294:innervation* / Q000473:pathology / Q000503:physiopathology
D005768:Gastrointestinal Hormones; D054439:Ghrelin; D007328:Insulin; D020738:Leptin; D036361:Peptide Hormones; D019894:Peptide YY; D052216:Glucagon-Like Peptide 1