Cystic fibrosis (CF) is caused by abnormalities in a gene called CFTR. This abnormality can affect many organs including the structure and function of the pancreatic ducts. These pancreatic ducts are tube-like structures that carry digestive enzymes produced in the pancreas to the intestines. When the gene is not working properly it causes the ducts to get clogged, inflamed, and sometimes degrade. In up to 50% of adults living with CF, this process affects the surrounding insulin-producing “beta cells”, causing CF-related diabetes (CFRD) leading to reduced insulin levels.
Over time CF changes the entire pancreas structure. A healthy pancreas is mostly made up of acinar cells (that secrete enzymes for digestion) and ducts (that carry the enzymes to the gut), with some beta cell clusters scattered throughout. In CF, the pancreas is filled with scar tissue and fat cells. Interestingly it retains many beta cells. This suggests that the cause of diabetes in CF may be due to more than just a decrease in the number of cells producing insulin, including the following possibilities.
- The inflamed ducts may be releasing molecules that stress beta cells and reduce their ability to
- The duct “injury” in CF attracts many immune cells and inflammatory cells to try to heal the pancreas. These efforts can mistakenly harm the beta cells.
- The altered pancreas structure in CF may damage blood vessels that are important for beta cells to function. For example, beta cells need blood vessels to measure blood sugar levels and to release the appropriate amount of insulin into the bloodstream to travel through the rest of the body.
As researchers increase their efforts to find out how genetic abnormalities in CF are damaging the pancreas, they are getting closer to developing specialized treatments for patients with CFRD.
About the author
Victoria Johnston
Victoria is an MSc student specializing in cystic fibrosis disease of the pancreas. Her research focuses on understanding the pancreatic microenvironment changes that occur in cystic fibrosis and how they may be causing diabetes.
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