Previous results have demonstrated that short-term dieting attenuates neuronal inhibitory control on appetite measured with blood-oxygen-level-dependent (BOLD) responses to a food cue task. Because recent studies have suggested that functional connectivity measured during the task is strongly predictive of disease states, we sought to investigate the effect of weight loss on brain functional connectivity during the picture viewing task. Sixteen healthy obese (10F/6M, age 44.4±8 years, BMI 32.7±2) and 9 type 2 diabetes (T2DM) obese subjects (5F/4M, age 48±9, BMI 33.9±2) underwent functional MRI (fMRI) before and after an 8-week low-calorie diet. Brain connectivity (BOLD) was recorded while subjects viewed preselected images (high-calorie food, low-calorie food, and non-food). Participants lost 2.9±2.8 kg (p<0.05) weight after the diet. Using intrinsic connectivity distribution (ICD) analysis, there was a significant diet effect (p< 0.01) in the inferior pons, hypothalamus, and inferior medial hippocampus across all subjects. Diet by group interaction in ICD (p <0.001) was observed in the inferior anterior amygdala, inferior medial hippocampus, and hypothalamus, brain regions involved in the modulation of emotion and glucose metabolism. These results highlight the adaptive nature of neuronal control on diet and provide novel evidence for a variable nature of inhibitory neuronal adaptions in metabolic diseases.
C. Watt: None. T.K. Stanley: None. C. Lacadie: None. K.W.Y. Lam: None. M. Savoye: None. R. Sinha: None. T. Constable: None. D. Seo: None. J.J. Hwang: Research Support; Self; General Electric. R. Belfort-DeAguiar: Research Support; Self; Silver Palate Kitches.
National Institute of Diabetes and Digestive and Kidney Diseases (P30DK045735, K23 DK098286-02, R01DK020495); National Institutes of Health (UL1TR001863)