The secret life of insulin-producing cells
The insulin-producing cells in the pancreas play a crucial role in the management of our blood sugar levels. If they don’t work properly, the body can no longer cope with glucose.
According to the World Health Organization (WHO), 347 million people worldwide are living with diabetes, and this figure is growing fast. Unless it is treated effectively, this chronic disease can cause complications that severely impair patients’ quality of life.
It also affects their life expectancy. By 2030, the WHO expects diabetes to be the world’s seventh leading cause of death.
There are two main types of diabetes. Type 2 diabetes is frequently preventable, and it is usually possible to avoid or delay the appearance of symptoms. Type 1 diabetes is an autoimmune disease whose origins remain puzzling. New insights that would help to refine prevention and management, applicable to any type of diabetes, could further improve the prospects, enabling more of us to stay healthier longer.
The EU-funded project BetaImage set out in 2008 to take diabetes research and treatment a step further. The project’s team has developed new imaging techniques that allow researchers to find out more about beta cells, the pancreatic cells that produce insulin.
The many faces of diabetes
Insulin enables the body to absorb glucose from the bloodstream. If the body does not produce enough of it, blood sugar can rise to harmful levels. This lack or loss of beta cell function is a main cause of diabetes. Other cases are due to a physiological inability to process insulin, although in fact both factors often combine.
Beta cells are located in parts of the pancreas referred to as the ‘islets of Langerhans’. They are destroyed as the disease progresses. How this correlates with the disease’s progression is currently unclear.
“Losing beta cells is something that happens in every patient in the long run,” says Prof. Martin Gotthardt of Radboud University Medical Centre in the Netherlands, BetaImage’s project coordinator. “But the patients may be at completely different stages of the disease when they are diagnosed. This may have implications for the treatment, and right now, we don’t adapt our treatment to that.”
A clearer image of pancreatic function
A safe, non-invasive way to check the state of patients’ beta cells could help to make treatments more effective, and the BetaImage team was determined to provide it. As one of several promising outcomes, the team has identified targets specific to these beta cells and developed radioactive tracer molecules that bind to them, making the cells visible for imaging equipment that detects this radiation.
Prof. Gotthardt is quick to point out that this technique has only just entered clinical trials and will not be widely available for several years. He adds that the initial results are encouraging and that the possibilities extend well beyond establishing beta cell mass.
Different tracers can potentially be used to assess different aspects – for example, if the beta cells are active, or if they are under attack from the immune system.
Another technology developed by the project will allow scientists to keep tabs on actual living islets. It takes existing optical coherence tomography to new heights by achieving near-cellular resolution.
The enhanced technique is known as optical coherence microscopy. It cannot be used to examine the pancreases of diabetes patients as it cannot ‘look’ far enough into the body (it is based on light, which cannot penetrate far beyond the surface of biological tissue). It does, however, offer unprecedented possibilities for diabetes research, where it can for example be used to observe the isolated pancreases of test animals.
“You can actually see differences between islets in a three-dimensional manner in a living pancreas, which until now in a living animal was not possible,” says Prof. Gotthardt.
The project ended in March 2013. Its results are feeding into a new project, BetaTrain, which is cross-validating new imaging technologies for use in diabetes imaging centres across Europe.