The gastrointestinal tract and its nervous system have numerous functions related to the uptake of food and they also play an important role in the development of adiposity. The Institute of Nutritional Medicine at the University of Hohenheim, Germany carries out numerous projects aimed at investigating the relationships between food uptake, digestive and nervous systems, thus making the institute an excellent partner in the “Bioactive Plant Foods” network.
The Institute of Nutritional Medicine at the University of Hohenheim includes the disciplines of nutritional medicine, immunology and prevention and is mainly focused on research into adiposity and malnutrition, immunology and intestinal barrier, food incompatibilities and allergies, working on nutritional medicine topics of current scientific and commercial interest.One particular topic, the “intestinal barrier”, is mainly focused on the intestinal wall, a mucosal surface providing an interface between the external environment (intestines containing food and bacteria) and the human host. “The intestinal wall is a very complicated structure: on the one hand, it takes up food and on the other, it prevents bacteria from entering the human body,” explained Prof. Dr. Stephan C. Bischoff, director of the institute. The gastrointestinal tract is endowed with a local nervous system, which is referred to as the enteric nervous system, and this system autonomously regulates the activity of the digestive tract. Studies have shown that the enteric nervous system regulates the uptake of food by interacting with a broad range of intestinal cells. This is of particular interest in terms of adiposity.
The gastrointestinal tract is also the focus of projects dealing with adiposity. “Up until now, the brain and fat tissue have been the major areas dealt with by researchers investigating the uptake of food; however, it also plays an important role in the regulation of appetite,” explains Bischoff. Gastrointestinal hormones play an important role in the development of adiposity because they regulate an individual’s appetite. The gastrointestinal wall affects the function of the liver amongst other things, as bacteria cross the gut barrier and lead to inflammatory reactions. This condition, which is referred to non-alcoholic fatty liver disease (NAFLD), is related to the metabolic syndrome.In addition to the intestinal barrier, the intestinal flora also plays an important role in the development or prevention of diseases. Probiotic products are considered functional foods because they provide health benefits beyond the traditional nutrition function. They are also subject to investigation at the Institute of Nutritional Medicine. Some chronic gut diseases, for example Crohn’s disease, are associated with changes in the intestinal flora. The Hohenheim researchers are investigating these alterations with the aim of developing new therapeutic approaches.The researchers’ work is funded by the Adiposity competence network, which was established in 2009. The competence network consists of eight research consortia involving the University of Hohenheim, the University Hospitals of Tübingen, Heidelberg and Aachen as well as Stuttgart Hospital. The “Adiposity and Gastrointestinal Tract” research consortium is coordinated by the University of Hohenheim under Prof. Bischoff and was established on the initiative of the Centre for Nutritional Medicine.
The Institute of Nutritional Medicine is also a partner in the “Bioactive Plant Foods” network that focuses mainly on the topic of adiposity. According to Prof. Bischoff, the broader public and nutritional scientists have long lacked awareness of functional foods. However, studies have shown that bioactive plant products are functionally active and they have been shown to have a therapeutic and preventive potential. “Further studies would be required to assess the medical benefit of such substances,” said Bischoff. A major issue related to functional foods is that they have been shown to have an effect when found in their natural matrix, but not in their isolated form. Another problem is the lack of a uniform definition of functional foods. “For me, probiotic yoghurt is a functional food item as it contains probiotic bacteria, special kinds of bacteria that are believed to be beneficial to our overall health, as functional components,” said Bischoff. “It would also be possible to add secondary plant substances with healthpromoting properties to the yoghurt.” The Institute of Nutritional Medicine has not yet carried out studies on amaranth and quinoa, which are the major focus of the network. Although the selection of these two plants is, according to Professor Bischoff, a risky choice from a commercial perspective due to the lack of data, the Hohenheim researchers are nevertheless interested in scientifically investigating new innovative approaches involving the two species. In addition to carrying out basic research, the Institute of Nutritional Medicine also carries out clinical studies involving human patients. These studies are carried out by the institute’s Metabolic Unit. The studies can be part of academic research programmes and can also be carried out on behalf of industry. One example involves adipose adults and adolescents being examined in rooms that resemble clinical practices, and researchers focusing on diseases associated with adiposity.