The Conversion of Pancreatic α-cells to β-cells

In a normal patient, the pancreatic α-cells and β-cells are kept at a stable level, where α-cells divide to form more α-cells and β-cells divide to form more β-cells. This study demonstrates the effect of α-cells being converted to β-cells. But various damages to the pancreas and other internal organs can cause an unforeseen difference in the cell types. In rats, a toxic diet can cause liver cells to form in the pancreas and intestinal cells to form in the liver. Because of this 'transdifferentiation' phenomena, Thorel and colleagues develop an idea where certain cells in the body are being converted into a different, but necessary cell.

To study the effects of diabetes, first, Thorel et al. chemically destroyed almost all the β-cells within adult mice. These pancreatic β-cells are responsible for secreting insulin, which is essential for the control of the blood glucose under physiological levels. For type 1 diabetes, the β-cells are destroyed and in type 2 diabetes, there are insufficient or nonfunctional β-cells to compensate for insulin resistance. In either case of diabetes, the abnormally high blood glucose levels can cause kidney, eye and nerve damage, and cardiovascular disease.

After the destruction of the β-cells , the mice were then kept alive with insulin treatment, and the regeneration of the cells was studied. It was observed that it was not the rarely survival of the remainder β-cells that kept the rats in sufficient, regenerated β-cell count. When Thorel et al. searched for the answers to the replenished β-cells, it was noted that the new cells arose from the reprogramming of the pancreatic α-cells. Also, once the new β-cells were replicated from the conversion, it seems that the β-cells do not take over the replication process; therefore, α-cell counts become diminished. It might be important to note that α-cells may become necessary to be replenished to maintain a correct glucagon/insulin ratio.

This work has a potential to be the starting point for an alternative therapy for diabetes treatment. Because the α-cell count is usually healthy and abundant, this interconversion between the two types of cells can be a pivotal approach to curing diabetes.

Shu Ho

http://www.nature.com/nature/journal/v464/n7292/full/4641132a.html