But now, research led by scientists at Beth Israel Deaconess Medical Center (BIDMC) and Oregon Health & Science University has identified a third abnormality that could play an important role in the development of obesity-induced Type 2 diabetes. Reported in the journal Nature, which appears in its Advance Online format today, the study describes a previously unrecognized role for glucose-sensing neurons in the onset of the disease – in other words, an important component of Type 2 diabetes may indeed be “in your head.”
“For many years we’ve known that subpopulations of neurons in the brain become ‘excited’ by glucose,” explains Bradford Lowell, MD, PhD, an investigator in the Division of Endocrinology, Diabetes and Metabolism at BIDMC and Professor of Medicine at Harvard Medical School (HMS). “But we haven’t understood exactly how or why this is significant. With this study, we show that these neurons sense increases in glucose and then initiate responses aimed at returning blood-glucose levels to normal. This is the first demonstration that glucose-sensing by neurons plays an important role in responding to rising blood glucose levels.” This finding, adds Lowell, who served as the study’s co-senior author together with Michael Cowley, PhD, of the Division of Neuroscience, Oregon Health & Science University, could potentially lead to novel treatments for Type 2 diabetes.
Knowing that the pro-opiomelanocortin (POMC) neurons regulate body weight in both mice and humans, co-lead authors Laura Parton, PhD, Chian Ping Ye, PhD, Roberto Coppari, PhD, and Pablo Enriori, PhD, decided to study the electrical properties of these cells in an animal model.
“New advances in genetic techniques have allowed us to express green fluorescent proteins [GFP] specifically in one cell type,” explains Parton, a member of the Lowell laboratory at BIDMC and Postdoctoral Research Fellow at HMS. “The advantage of expressing a fluorescent marker specifically in one type of neuron is the ability to identify and distinguish these cells from the many hundreds of other cell types that are present in the brain.”
As predicted, the electrophysiology experiments demonstrated that POMC neurons became electrically excited by a rise in glucose, similar to what would occur after eating a meal. The authors then went on to disrupt glucose-sensing abilities specifically in the POMC neurons – and confirmed that these neurons play a critically important role in regulating blood-glucose levels in mice. And, as is the case in pancreatic beta cells, the glucose-sensing ability of POMC neurons was shown to be defective in the mice with obesity-induced Type 2 diabetes.
“What is apparently happening,” says Parton, “is that an increase in the activity of the mitochondrial uncoupling protein 2 (UCP2), is behind the loss of glucose-sensing ability in the POMC neurons. Increased activity of UCP2 is known to cause loss of glucose-sensing and defective insulin secretion by pancreatic beta cells and this study now shows that a similar phenomenon also occurs in neurons.”
“These new findings add to our understanding of Type 2 diabetes at a critically important time,” adds Lowell. “The incidence of the disease has risen to epidemic proportions, and obesity is a big risk factor for the disease. The discovery that defects in glucose-sensing by the brain may also be contributing to Type 2 diabetes could help lead to new therapeutic strategies for this widespread problem.”
Toward a 'smart' patch that automatically delivers insulin when needed
18.01.2017 | American Chemical Society
127 at one blow...
18.01.2017 | Stiftung Zoologisches Forschungsmuseum Alexander Koenig, Leibniz-Institut für Biodiversität der Tiere
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).
Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...
10.01.2017 | Event News
09.01.2017 | Event News
05.01.2017 | Event News
18.01.2017 | Power and Electrical Engineering
18.01.2017 | Materials Sciences
18.01.2017 | Life Sciences