New research part-funded by JDRF has found that insulin production rapidly declines after diagnosis but then stabilises after seven years. These findings open new doors to develop methods to preserve and regenerate remaining beta cells in the pancreas years after diagnosis.
Historically, researchers thought that all beta cells are destroyed in type 1 diabetes (T1D). In recent years, research has found that some people continue to produce tiny amounts of insulin years after diagnosis due to a small pool of remaining beta cells, some of which may retain their function. There is little knowledge on the long-term changes (beyond 5 years) in beta cell function after diagnosis.
The research team, based at the University of Exeter Medical School, wanted to get an understanding of long-term insulin production and beta cell function. To track insulin production, they measured a molecule called C-peptide in the urine of 1,549 people with T1D from the UK, up to 40 years after diagnosis. C-peptide is released from beta cells at the same time as insulin is released, so it can be used as a marker of insulin production in the body.
They found that there were two clear phases of insulin production. After diagnosis, insulin production decreased on average by 47% a year for seven years. This is followed by a stable period where insulin levels declined much more slowly or plateaued.
This finding is a step forward in understanding T1D and contradicts older beliefs that beta cells lose all insulin-producing ability after diagnosis. It indicates the process of beta cell destruction may not be as complete as we once believed and may change over time. Understanding the differences between the two phases will give crucial insights into understanding beta cell survival, and will open doors for new strategies to regenerate the remaining beta cells and restore insulin independence.
What’s happening in this area in Australia
Associate Professor Shane Grey at the Garvan Institute is investigating regeneration of beta cells in zebra fish, with the hopes that this will give us the insight to take regeneration into humans and even restore the body’s ability to produce insulin. This research is funded by a T1DCRN Innovation Award – it is the first time anyone has investigated this angle for T1D.
Associate Professor Helen Thomas at St Vincent’s Institute in VIC is investigating whether a new drug could protect beta cells from immune attack. She is undergoing final steps in the lab with the aim to take this approach to clinical trials in the next few years. It is hoped that the drug will stop or slow the immune processes leading to T1D.
Associate Professor Anandwardhan Hardikar, funded by the T1DCRN and the Leona M. and Harry B. Helmsley Charitable Trust, is designing a simple detection kit to detect beta cell loss before T1D diagnosis. If successful, this test to measure beta cell loss could significantly accelerate development of therapies to prevent or delay T1D, and if T1D is picked up early, reduce the risk of life-threatening complications such as diabetic ketoacidosis at diagnosis, and give families more time to adjust.