Scientists at the Gladstone Institutes have discovered a key protein that regulates insulin resistance—the diminished ability of cells to respond to the action of insulin and which sets the stage for the development of the most common form of diabetes. This breakthrough points to a new way to potentially treat or forestall type 2 diabetes, a rapidly growing global health problem.
In a paper being published online this week in the Proceedings of the National Academy of Sciences, researchers in the laboratory of Gladstone Investigator Katerina Akassoglou, PhD, describe an unexpected role of the p75 neurotrophin receptor in controlling how the body processes sugar. Called p75NTR, this receptor protein is usually associated with functions in neurons.
"We identified that p75NTR is a unique player in glucose metabolism," said Dr. Akassoglou, who is also an associate professor of neurology at the University of California, San Francisco, with which Gladstone is affiliated. "Therapies targeted at p75NTR may represent a new therapeutic approach for diabetes."
The pancreas makes a hormone called insulin that processes glucose, moving it from the bloodstream into the body's cells where it is used for energy. Insulin resistance is a key feature of Type 2 diabetes, in which glucose builds up in the bloodstream and the body's cells are unable to function properly. According to the Centers for Disease Control and Prevention, more than 20 million Americans have type 2 diabetes.
"Type 2 diabetes has become a very serious health problem and it is increasing at an alarming rate," said Lennart Mucke, MD, who directs the institute in which the research was conducted. "These findings provide an important new avenue for developing better therapies to combat this deadly disease—the seventh leading cause of death in the United States."
Complex signaling interactions between several different types of tissue—including fat, liver, muscle and brain—regulate glucose metabolism. Because p75NTR is found in fat and muscle tissue and participates in many important functions in the cell, Gladstone scientists hypothesized that p75NTR might also help to regulate glucose metabolism.
To study this, the researchers used mice that lacked the genes for p75NTR. They compared these mice to normal mice and discovered that those lacking p75NTR were more responsive to insulin when fed a normal diet. Second, they used some molecular biology tricks to block the action of the p75NTR protein in fat cells. This also resulted in increased glucose absorption in response to insulin. In contrast, when they caused the fat cells to make more p75NTR, glucose absorption was reduced. Additionally, the researchers found that another important regulatory molecule, Rab5, played a key role in p75NTR's impact on metabolism.
"Importantly, regulation by p75NTR enhanced insulin's effectiveness in normal lean mice on a normal diet," said Bernat Baeza-Raja, PhD, postdoctoral fellow and lead author of the study. "Because these mice already process glucose efficiently, the actions of p75NTR on glucose transport indicate a direct role of this protein in the regulation of glucose metabolism."
"Our studies of p75NTR's unanticipated role in regulating glucose metabolism suggest a new target for drug therapies," said Dr. Akassoglou. "Future work is needed to test whether this finding may translate into a potential treatment."
This study was a collaborative work between scientists at Gladstone, the University of California, San Diego (UCSD), the University of Michigan and the University of Houston. Other scientists who participated in this research at Gladstone include Natacha Le Moan, PhD, Christian Schachtrup, PhD, Dimitrios Davalos, PhD, and Eirini Vagena. Jerrold Olefsky, PhD, and Pingping Li, PhD, at UCSD were co-senior and co-first authors, respectively. Funding was provided by a variety of sources, including the National Institutes of Health, the University of California San Francisco Liver Center and Diabetes and Endocrinology Center and the R. A. Welch Foundation.
About the Gladstone Institutes
Gladstone is an independent and nonprofit biomedical-research organization dedicated to accelerating the pace of scientific discovery and innovation to prevent, treat and cure cardiovascular, viral and neurological diseases. Gladstone is affiliated with the University of California, San Francisco.
Diane Schrick | EurekAlert!
Researchers develop eco-friendly, 4-in-1 catalyst
25.04.2017 | Brown University
Transfecting cells gently – the LZH presents a GNOME prototype at the Labvolution 2017
25.04.2017 | Laser Zentrum Hannover e.V.
More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.
Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...
Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.
"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
20.04.2017 | Event News
18.04.2017 | Event News
03.04.2017 | Event News
25.04.2017 | Physics and Astronomy
25.04.2017 | Materials Sciences
25.04.2017 | Life Sciences