Canadian researchers have identified how vitamin K helps prevent diabetes, a finding that could lead to new therapeutic applications for a disease that affects one in 11 people worldwide and has no cure.
Several studies have previously suggested a link between a reduced intake of vitamin K and an increased risk of diabetes. However, the biological mechanisms by which vitamin K protects against diabetes remained a mystery until now.
The team from the Universite de Montreal (UdeM) found a potentially protective role of vitamin K and gamma-carboxylation in beta cells.
Vitamin K is a micronutrient known for its role in blood clotting, in particular in gamma-carboxylation -- an enzymatic reaction essential to the process.
The study, published in the journal Cell Reports, determined that the enzymes involved in gamma-carboxylation and therefore in the use of vitamin K were present in large quantities in pancreatic beta cells, the very cells that produce the precious insulin that controls blood sugar levels.
"Diabetes is known to be caused by a reduction in the number of beta cells or by their inability to produce enough insulin, hence our keen interest in this novel finding," said Mathieu Ferron, associate research professor of medicine at UdeM.
"We were able to identify a new gamma-carboxylated protein called ERGP," added Julie Lacombe, who conducted the work in Ferron's laboratory.
"Our study shows that this protein plays an important role in maintaining physiological levels of calcium in beta cells in order to prevent a disturbance of insulin secretion. Finally, we showed that vitamin K through gamma-carboxylation is essential for ERGP to perform its role."
This is the first time in 15 years that a novel vitamin K-dependent protein has been identified, opening a new field of research in this area.
