A team led by Gilles Mithieux, Director of Inserm's Unit 855 "Nutrition and the Brain" in Lyon, has managed to explain the biological mechanisms behind these properties. The researchers describe in detail the chain reactions triggered by digesting proteins, sending a 'satiety' message to the brain long after a meal. Their results, published on 5 July in the Cell review, will make it possible envisage improved care for obese or overweight patients.
The team of researchers from Inserm, CNRS and the Universit¨¦ Clause Bernard Lyon 1 has managed to shed light on the sensation of fullness experienced several hours after a protein-rich meal. This sensation is explained by messages exchanged between the digestive system and the brain, initiated by the dietary proteins that are mainly found in meat, fish, eggs or even some cereal-based products.
In previous studies, researchers proved that consuming dietary proteins triggers glucose synthesis in the intestine, after periods of food assimilation (a function known as gluconeogenesis). The glucose that is released in the blood circulation (portal vein) is detected by the nervous system, which sends an "appetite-suppressing" signal to the brain. Best-known in the liver and kidneys from which it supplies other organs with sugar, gluconeogenesis in the intestine sends an "appetite-suppressing" message after meals, characteristic of the sensation of "fullness".
In this new study, the researchers managed to accurately describe how digesting proteins triggers a double-loop of chain reactions involving the ventral (via the vagus nerve) and dorsal (via the spinal cord) peripheral nervous systems.
The in-depth study of biological mechanisms identified the specific receptors (¦Ì-opioid receptors ) found in the portal vein nervous system, at the outlet of the intestine. These receptors are inhibited by oligo-peptides, produced during protein digestion.
In an initial phase, the oglio-peptides act upon the ¦Ì-opioid receptors, which send a message through the vagus nerve and the spinal chord to areas of the brain specially-designed to receive these messages.
During a second phase, the brain sends a return-message that triggers gluconeogenesis via the intestine. The intestine then sends the "appetite-suppressing" message to areas of the brain that control food intake, such as the hypothalamus1. Consumption of dietary proteins
Inserm Press Office | EurekAlert!
Fingerprint' technique spots frog populations at risk from pollution
27.03.2017 | Lancaster University
Parallel computation provides deeper insight into brain function
27.03.2017 | Okinawa Institute of Science and Technology (OIST) Graduate University
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
27.03.2017 | Earth Sciences
27.03.2017 | Life Sciences
27.03.2017 | Life Sciences