Experimental Surgery and Brain Imaging Applied to Nutrition Studies in Pig and Minipig Models

The pig model is increasingly used in biomedical research and notably for nutrition studies. In addition to have numerous similarities with the human, in terms of anatomy and physiology, the pig has a brain that is structurally and functionally very close to that of non-human primates. The pig model consequently represents a unique opportunity to explore the neurophysiological determinants of the eating behavior and related pathologies. The aim of this conference is to present some examples of research using pigs and minipigs as models to study obesity and eating disorders, and benefiting from modern surgical and imaging techniques. The PRISM AniScans imaging platform and the associated experimental facilities will be presented. First, a pig model for the study of food preferences and aversions will be introduced, combining experimental surgery to modulate post-ingestive signals, behavioral tests to investigate food preferences and motivation, as well as brain imaging to assess the brain responses further to olfactogustatory and/or visceral food stimulations. Potential applications in the field of human and animal nutrition and health will be presented. Second, diet-induced obesity will be described in adult minipigs from different breeds (Göttingen, Pitman-Moore, Yucatan), with an emphasis on the behavioral and brain alterations induced by deleterious diets and weight gain. Comparing the respective effects of diets differing on their lipids and/or carbohydrates sources will highlight the importance of nutrient quality on eating behavior and health. Bariatric surgery alternatives will then be presented, such as the chronic vagus nerve stimulation and the deep brain stimulation, two promising therapeutic approaches to fight against obesity. A focus will be done on the state-of-the-art approaches used to explore these solutions (e.g. keyhole surgery, implantable devices, neuronavigation-assisted brain surgery, etc.), and research perspectives will be presented.