In people with Type 2 diabetes, fat and muscle cells can’t absorb glucose from the blood as well as they usually can. This is called insulin resistance and can lead to high levels of glucose in the blood. A molecule called GLUT4 helps glucose to leave the blood and enter fat and muscle cells, but we don’t know exactly how it works. Understanding this could help to develop new drugs to prevent insulin resistance in people with or at risk of Type 2 diabetes.
Background to research
Following a meal, insulin is released into the bloodstream. This causes glucose to be taken into fat and muscle cells, lowering levels of glucose in the blood. This keeps blood glucose at a safe and constant level.
In people with Type 2 diabetes, this process doesn’t work properly. This is known as insulin resistance, but we don’t know what causes insulin resistance.
Scientists can look closely at how glucose in the blood is absorbed into fat and muscle. They know is happens via a molecule called a transporter, or GLUT4. A specific tag called a glycan is added to GLUT4. This glycan tag is needed to help GLUT4 to move from where it’s stored inside fat and muscle cells to their surface. GLUT4 needs to be at the cell surface before it can transport glucose inside.
Finding out what GLUT4’s glycan tag is made up of could tell us more about how glucose is absorbed from the blood, and why this might stop working in people with Type 2 diabetes.
Professor Bryant’s PhD student will study the structure of GLUT4’s glycan tag. This will provide crucial information on the size of the tag and what it’s made of.
Once they know this, they will try to manipulate the behaviour of the tag in cells grown in the lab. They hope to understand more about how the tag interacts with other molecules inside the cell. This way, they can build a picture of how GLUT4 moves from storage inside the cell to the surface.
Potential benefit to people with diabetes
Understanding the biology behind insulin resistance will help us understand why Type 2 diabetes develops. In the future, this could also help scientists to develop new drugs that improve insulin sensitivity in people with Type 2 diabetes.