London – A team of researchers suggested that vitamin A plays a major role in improving the insulin producing β-cell´s function, despite that former studies didn’t show any link between this vitamin and diabetes.
Researchers from the Lund University, University of Gothenburg, Oxford Centre for Diabetes, and King’s College (London) discovered that insulin-producing cells contain cell surface receptor for vitamin A.
Albert Salehi, senior researcher at the Lund University Diabetes Centre in Sweden said there are no unnecessary surface receptors in human cells. They all serve a purpose but which, in many cases, is still unknown and because of that they are called “orphan” receptors.
Salehi added that vitamin A plays an important role in the development of beta-cells in the early stages of life, and during Pathophysiological conditions, like inflammatory ones.
Researchers have mapped 220 different receptors on the surface of the beta cell. In order to study the role of the vitamin in cases of diabetes, the researchers worked on insulin cells from mice and non-diabetic and type 2 diabetic donors. By partially blocking the vitamin A receptor and challenging the cells with sugar, they could see that the cells’ ability to secrete insulin deteriorated.
Salehi said: “We saw close to a 30% reduction. Impaired cell survival and insulin secretion are key causes of type 2 diabetes.”
The same tendency could be seen when comparing insulin cells from type 2 diabetic donors. Cells from patients with type 2 diabetes were less capable of insulin secretion compared with cells from diabetes-free people.
The researchers also saw that the beta-cells’ resistance to inflammation decreases in the absence of vitamin A.
“In animal experiments it is known that newborn mice need vitamin A to develop their beta-cells in a normal way.
Most likely, the same applies to human beings. Children must absorb a sufficient amount of vitamin A through their diet,” says Albert Salehi.
Vitamin A is found mainly in milk, eggs, liver, carrots, melon, sweet potatoes, and spinach.