BACKGROUND. A polymorphism in the fat mass and obesity-associated gene (FTO) is linked to enhanced neural sensitivity to food-cues and attenuated ghrelin suppression. Risk allele carriers regain more weight than non-carriers after bariatric surgery. It remains unclear how FTO variation affects brain function and ghrelin following surgery. METHODS. Resting-state functional magnetic resonance imaging (RS-fMRI) and cue-reactivity fMRI with high-/low-caloric food-cues were performed at pre-surgery and 1-, 6-, and 12-months post-surgery to examine brain function in 16 carriers with one copy of the rs9939609 A allele (AT) and 26 non-carriers (TT). Behavioral assessments up to five years post-surgery were also conducted. RESULTS. AT relative to TT group had smaller BMI-loss at 12 to 60 months post-surgery and lower resting-state activity in posterior cingulate cortex following LSG (group-by-time interaction effects). Meanwhile, AT relative to TT group showed greater food-cue responses in dorsolateral prefrontal cortex (DLPFC), dorsomedial prefrontal cortex (DMPFC) and insula (group effects). There were negative associations of weight-loss with ghrelin and greater activation in DLPFC, DMPFC and insula in AT but not TT group. CONCLUSION. These findings indicate that FTO variation is associated with the evolution of ghrelin signaling and brain function after bariatric surgery, which might hinder weight-loss.
Guanya Li, Yang Hu, Wenchao Zhang, Jia Wang, Lijuan Sun, Juan Yu, Peter Manza, Nora D. Volkow, Gang Ji, Gene-Jack Wang, Yi Zhang
This file is in Adobe Acrobat (PDF) format. If you have not installed and configured the Adobe Acrobat Reader on your system.
PDFs are designed to be printed out and read, but if you prefer to read them online, you may find it easier if you increase the view size to 125%.
Many versions of the free Acrobat Reader do not allow Save. You must instead save the PDF from the JCI Online page you downloaded it from. PC users: Right-click on the Download link and choose the option that says something like "Save Link As...". Mac users should hold the mouse button down on the link to get these same options.