In-Seon Lee1,2, Stephanie Kullmann3, Klaus Scheffler4,5, Hubert Preissl3,6, Paul Enck1. 1. Departments of Psychosomatic Medicine and Psychotherapy. 2. IMPRS for Cognitive and Systems Neuroscience, Tübingen, Germany. 3. Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, German Center for Diabetes Research (DZD), Department of Internal Medicine, Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry. 4. Biomedical Magnetic Resonance. 5. Department of High-Field Magnetic Resonance, Max Planck Institute for Biological Cybernetics, Tübingen, Germany. 6. Institute of Pharmaceutical Sciences, Interfaculty Centre for Pharmacogenomics and Pharma Research, Department of Pharmacy and Biochemistry, University of Tübingen, Tübingen, Germany.
Abstract
Background: High-fat meals are associated with dyspeptic symptoms in functional dyspepsia (FD) patients. It is still unclear how fat is processed, or how FD symptoms and neuronal activities are modulated by psychological factors. Objective: We investigated brain activity by functional magnetic resonance imaging (fMRI) after the ingestion of high- and low-fat foods with correct/incorrect fat information. Design: We compared 12 FD patients and 14 healthy controls (HCs). We recorded resting-state fMRI on four different days before and after ingestion of four yogurts (200 mL, 10% or 0.1% fat, "low fat" or "high fat" label). Results: FD patients showed more pronounced dyspeptic symptoms than did HCs, and symptoms were relieved less after consuming high fat-labeled yogurt than low fat-labeled yogurt, irrespective of the actual fat content. This is indicative of either a placebo effect of low-fat information or a nocebo effect of high-fat information on symptom expression. FD patients showed greater activity than did HCs in occipital areas before and after ingestion regardless of fat content and label, as well as greater activity in the middle frontal gyrus before ingestion. In addition, functional connectivity (FC) from the insula to the occipital cortex (I-O) increased after high fat ingestion and decreased after low fat ingestion in FD patients. FC from the insula to the precuneus (I-P) was higher in FD patients than in HCs after ingestion of low fat-labeled yogurt. In FD patients, I-O FC negatively correlated with nausea and I-P FC with FD symptom intensity, food craving, and depression. Conclusions: Our results endorse the importance of psychological perception of food on the incidence of dyspeptic symptoms and on the altered brain activities. These findings show the importance of cognitive components in perceptions of fat, food craving, depression, and brain functions in pathophysiologic mechanisms of FD. This trial was registered at clinicaltrials.gov as NCT02618070.
Background: High-fat meals are associated with dyspeptic symptoms in functional dyspepsia (FD) patients. It is still unclear how fat is processed, or how FD symptoms and neuronal activities are modulated by psychological factors. Objective: We investigated brain activity by functional magnetic resonance imaging (fMRI) after the ingestion of high- and low-fat foods with correct/incorrect fat information. Design: We compared 12 FDpatients and 14 healthy controls (HCs). We recorded resting-state fMRI on four different days before and after ingestion of four yogurts (200 mL, 10% or 0.1% fat, "low fat" or "high fat" label). Results:FDpatients showed more pronounced dyspeptic symptoms than did HCs, and symptoms were relieved less after consuming high fat-labeled yogurt than low fat-labeled yogurt, irrespective of the actual fat content. This is indicative of either a placebo effect of low-fat information or a nocebo effect of high-fat information on symptom expression. FDpatients showed greater activity than did HCs in occipital areas before and after ingestion regardless of fat content and label, as well as greater activity in the middle frontal gyrus before ingestion. In addition, functional connectivity (FC) from the insula to the occipital cortex (I-O) increased after high fat ingestion and decreased after low fat ingestion in FDpatients. FC from the insula to the precuneus (I-P) was higher in FDpatients than in HCs after ingestion of low fat-labeled yogurt. In FDpatients, I-O FC negatively correlated with nausea and I-P FC with FD symptom intensity, food craving, and depression. Conclusions: Our results endorse the importance of psychological perception of food on the incidence of dyspeptic symptoms and on the altered brain activities. These findings show the importance of cognitive components in perceptions of fat, food craving, depression, and brain functions in pathophysiologic mechanisms of FD. This trial was registered at clinicaltrials.gov as NCT02618070.