Recent Findings Suggest Alternative Cause for Type 1 Diabetes
Tools to manage Type 1 diabetes: syringe with insulin, and blood glucose meter and test strips (Photo: stevepb at Pixabay)
Scientific research is all about discovering what is happening in the world around us, and within our own bodies. This means sometimes, new information is found that challenges our prior knowledge. Earlier this year, a study suggested that researchers and clinicians may have to change the way they think about type 1 diabetes (T1D) and which cells in the body are “at fault” in diabetics.
What is T1D?
T1D is a dangerous disease that is difficult to manage, and we do not yet have a cure for it. People diagnosed with T1D must keep up with multiple needles and finger pricks throughout the day and ensure that they are monitoring their diet and daily physical activity in order to be healthy. Even when type 1 diabetics are very careful, their disease can still pose many health risks.
In type 1 diabetics, the beta cells in the pancreas which produce and secrete insulin are being destroyed by immune system cells called T cells. Since people with T1D cannot produce their own insulin, they must take insulin injections.
What is insulin, and why is it so important?
Insulin is an important protein hormone that helps to manage blood-sugar levels. After eating, insulin is released from beta cells and communicates to cells throughout the body that they should take up the sugar glucose from the bloodstream since blood-sugar levels are high. Without this signal from the insulin hormone, cells cannot take up glucose from the blood.
This means without insulin, the cells in our body are unable to get the energy they need from the food that we consume. It also means that blood-sugar levels stay very high, a condition known as hyperglycemia. Having high blood-sugar regularly can cause various long-term complications such as damage to the nerves, kidneys, and blood vessels.
Insulin injections are an effective treatment for T1D, but learning more about what causes the disease can bring us closer to a cure.
What was previously thought about T1D?
Many studies have established that insulin-secreting beta cells are being destroyed by immune cells called T cells in T1D. Immune cells are trained to protect the body from infection by attacking foreign materials or unhealthy cells.
It was previously thought that T cells were attacking beta cells because they were always mistakenly identifying them as unhealthy. In this case, the T cells would be the ones at fault in this disease. Since T1D involves the immune system attacking the body’s own cells, T1D is classified as an autoimmune disorder.
What has recently been found about T1D?
A study published this year provided evidence that it might be inaccurate to blame T cells for making all of the mistakes in type 1 diabetes. Though T cells are still exhibiting autoimmunity, this study shows that they may have a good reason for doing so in certain cases.
The team working on this study found that a defective form of insulin protein can be found on the surface of beta cells in T1D. This type of protein is a target of the immune system because it is dysfunctional, due to misreading of RNA during protein production. When these dysfunctional insulin proteins are found on the beta cells, there is something wrong with the beta cells, rather than the T cells, in these T1D patients.
The study supports the concept that the autoimmunity against beta cells could be comparable to the immune response against cancer cells. This link makes sense since the immune system is trained to scan the body for dysfunctional and dangerous cells, such as cancer cells. Essentially, these findings suggest that the beta cells can be the ones making the mistakes that result in autoimmunity in T1D, and T cells are actually doing their job properly.
How does this change our approach to treating T1D?
When previous knowledge about diseases are challenged by new findings in scientific research, it is important to consider how ongoing research should be redirected. Since this recent study found that beta cells can give T cells a reason to target them in T1D, researchers should focus on identifying potential causes for the beta cell dysfunction.
Discovering new information in science can sometimes feel like taking one step forward and a few steps back. However, each novel finding brings medical experts closer to developing better treatments and potential cures for diseases such as T1D.
Emily Miraglia is an undergraduate student in biomedical science at Ryerson University. Connect with her on LinkedIn.