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.”
How the gut ‘talks’ to brown fat
Nanotubes built from protein crystals: Breakthrough in biomolecular engineering
15.11.2018 | Tokyo Institute of Technology
Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.
Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...
Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.
In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...
On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.
When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure
Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...
Physicists at ETH Zurich demonstrate how errors that occur during the manipulation of quantum system can be monitored and corrected on the fly
The field of quantum computation has seen tremendous progress in recent years. Bit by bit, quantum devices start to challenge conventional computers, at least...
09.11.2018 | Event News
06.11.2018 | Event News
23.10.2018 | Event News
15.11.2018 | Earth Sciences
15.11.2018 | Physics and Astronomy
15.11.2018 | Physics and Astronomy