OBJECTIVE: This study examined the effect of exenatide on brain activity measured by functional (f)MRI and on insulin secretion in lean and obese normal-glucose-tolerant individuals. RESEARCH DESIGN AND METHODS: The brain fMRI signal in response to high-calorie-content food pictures was measured with and without intravenous exenatide infusion in 10 lean and 10 obese healthy volunteers. Insulin secretion was measured with a two-step (+100 and +200 mg/dL) hyperglycemic clamp with exenatide and with saline infusion. RESULTS: The brain fMRI signal in response to food pictures in amygdala, insula, hippocampus, and frontal cortex was significantly greater in obese versus lean individuals. Intravenous exenatide significantly inhibited the fMRI signal in response to food pictures in obese individuals but did not affect the brain fMRI signal in lean subjects. Conversely, exenatide infusion caused an 18.5-fold increase in insulin secretion in lean individuals compared with an 8.8-fold increase in obese subjects. No significant correlation was observed between inhibition of the brain fMRI signal and increase in insulin secretion during exenatide infusion. CONCLUSIONS: Exenatide causes greater augmentation in insulin secretion in lean compared with obese individuals but inhibits the brain response to food pictures only in obese individuals.
OBJECTIVE: This study examined the effect of exenatide on brain activity measured by functional (f)MRI and on insulin secretion in lean and obese normal-glucose-tolerant individuals. RESEARCH DESIGN AND METHODS: The brain fMRI signal in response to high-calorie-content food pictures was measured with and without intravenous exenatide infusion in 10 lean and 10 obese healthy volunteers. Insulin secretion was measured with a two-step (+100 and +200 mg/dL) hyperglycemic clamp with exenatide and with saline infusion. RESULTS: The brain fMRI signal in response to food pictures in amygdala, insula, hippocampus, and frontal cortex was significantly greater in obese versus lean individuals. Intravenous exenatide significantly inhibited the fMRI signal in response to food pictures in obese individuals but did not affect the brain fMRI signal in lean subjects. Conversely, exenatide infusion caused an 18.5-fold increase in insulin secretion in lean individuals compared with an 8.8-fold increase in obese subjects. No significant correlation was observed between inhibition of the brain fMRI signal and increase in insulin secretion during exenatide infusion. CONCLUSIONS:Exenatide causes greater augmentation in insulin secretion in lean compared with obese individuals but inhibits the brain response to food pictures only in obese individuals.
Authors: J L Lancaster; L H Rainey; J L Summerlin; C S Freitas; P T Fox; A C Evans; A W Toga; J C Mazziotta Journal: Hum Brain Mapp Date: 1997 Impact factor: 5.038
Authors: Jack L Lancaster; Diana Tordesillas-Gutiérrez; Michael Martinez; Felipe Salinas; Alan Evans; Karl Zilles; John C Mazziotta; Peter T Fox Journal: Hum Brain Mapp Date: 2007-11 Impact factor: 5.038
Authors: L van Bloemendaal; D J Veltman; J S Ten Kulve; P F C Groot; H G Ruhé; F Barkhof; J H Sloan; M Diamant; R G Ijzerman Journal: Diabetes Obes Metab Date: 2015-07-22 Impact factor: 6.577
Authors: Ralph A DeFronzo; Ele Ferrannini; Leif Groop; Robert R Henry; William H Herman; Jens Juul Holst; Frank B Hu; C Ronald Kahn; Itamar Raz; Gerald I Shulman; Donald C Simonson; Marcia A Testa; Ram Weiss Journal: Nat Rev Dis Primers Date: 2015-07-23 Impact factor: 52.329
Authors: Luke E Stoeckel; Rosalyn E Weller; Edwin W Cook; Donald B Twieg; Robert C Knowlton; James E Cox Journal: Neuroimage Date: 2008-03-04 Impact factor: 6.556
Authors: P V Højberg; T Vilsbøll; R Rabøl; F K Knop; M Bache; T Krarup; J J Holst; S Madsbad Journal: Diabetologia Date: 2008-11-27 Impact factor: 10.122
Authors: Julio Rosenstock; Sylvia K Shenouda; Richard M Bergenstal; John B Buse; Leonard C Glass; Cory R Heilmann; Anita Y M Kwan; Leigh A MacConell; Byron James Hoogwerf Journal: Diabetes Care Date: 2012-03-19 Impact factor: 19.112
Authors: Paola Binda; Roy Eldor; Claudia Huerta; John Adams; John Lancaster; Peter Fox; Stefano Del Prato; Ralph DeFronzo; Muhammad Abdul-Ghani; Giuseppe Daniele Journal: Diabetes Metab Res Rev Date: 2019-05-06 Impact factor: 4.876
Authors: Jae Hyun Bae; Hyung Jin Choi; Kang Ik Kevin Cho; Lee Kyung Kim; Jun Soo Kwon; Young Min Cho Journal: Diabetes Metab J Date: 2019-11-04 Impact factor: 5.376