title: Neural responsivity to food cues in fasted and fed states pre and post gastric bypass surgery.
abstract: Reductions in mesolimbic responsivity have been noted following Roux-en-Y gastric bypass (RYGB; Ochner et al., 2011a). Given potential for postoperative increases in postprandial gut (satiety) peptides to affect mesolimbic neural responsivity, we hypothesized that: (1) post RYGB changes in mesolimbic responsivity would be greater in the fed relative to the fasted state and; (2) fasted vs. fed state differences in mesolimbic responsivity would be greater post-relative to pre-surgery. fMRI was used to asses neural responsivity to high- and low-calorie food cues in five women 1 mo pre- and 1 mo post-RYGB. Scans were repeated in fasted and fed states. Significant post RYGB decreases in the insula, ventromedial prefrontal cortex (vmPFC) and dorsolateral prefrontal cortex (dlPFC) responsivity were found in the fasted state. These changes were larger than neural changes in the fed state, which were non-significant. Preoperatively, fasted vs. fed differences in neural responsivity were greater in the precuneus, with large but nonsignificant clusters in the vmPFC and dlPFC. Postoperatively, however, no fasted vs. fed differences in neural responsivity were noted. Results were opposite to that predicted and appear inconsistent with the initial hypothesis that postoperative increases in postprandial gut peptides are the primary driver of postoperative changes in neural responsivity.
authors.affiliation: Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, USA; New York Obesity Nutrition Research Center, St. Luke's Roosevelt Hospital, NY 10025, USA. co2193@columbia.edu
authors.forename: Christopher N
authors.initials: CN
authors.lastname: Ochner
authors.forename: Blandine
authors.initials: B
authors.lastname: Laferrère
authors.forename: Ladan
authors.initials: L
authors.lastname: Afifi
authors.forename: Deniz
authors.initials: D
authors.lastname: Atalayer
authors.forename: Allan
authors.initials: A
authors.lastname: Geliebter
authors.forename: Julio
authors.initials: J
authors.lastname: Teixeira
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D001066:Appetite / Q000502:physiology; D002540:Cerebral Cortex / Q000503:physiopathology; D003342:Corpus Striatum / Q000503:physiopathology; D003463:Cues; D002149:Energy Intake; D005215:Fasting / Q000502:physiology* / Q000523:psychology; D005247:Feeding Behavior / Q000502:physiology* / Q000523:psychology; D005260:Female; D015390:Gastric Bypass / Q000523:psychology*; D052216:Glucagon-Like Peptide 1 / Q000378:metabolism; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D008959:Models, Neurological; D008960:Models, Psychological; D009767:Obesity, Morbid / Q000503:physiopathology* / Q000523:psychology / Q000601:surgery; D010446:Peptide Fragments; D019894:Peptide YY / Q000378:metabolism; D010775:Photic Stimulation; D011184:Postoperative Period; D019518:Postprandial Period / Q000502:physiology*; D017397:Prefrontal Cortex / Q000503:physiopathology*; D012201:Reward; D012528:Satiety Response / Q000502:physiology*; D055815:Young Adult
chemical_list: D010446:Peptide Fragments; D019894:Peptide YY; C061785:peptide YY (3-36); D052216:Glucagon-Like Peptide 1