Stable insulin secreting ducts formed by reprogramming of cells in the liver using a three gene cocktail and a PPAR agonist

With the long term aim of developing a new type of therapy for diabetes, we have investigated the reprogramming of liver cells in normal mice towards a pancreatic phenotype using the gene combination Pdx1, Ngn3, MafA. CD1 mice were rendered diabetic with streptozotocin and given a single dose of Ad-PNM, an adenoviral vector containing all three genes. Ad-PNM induced hepatocytes of the liver to produce insulin and the blood glucose became normalized. But over several weeks the insulin-positive cells were lost and the blood glucose rose back to diabetic levels. Simultaneous administration of a PPAR agonist, WY14643, caused remission of diabetes at a lower dose of Ad-PNM, and also caused the appearance of a population of insulin-secreting ductal structures in the liver. The insulin-positive ducts were stable and were able to relieve diabetes long term. We show that the effect of WY14643 is associated with the promotion of cell division of the ductal cells, which may increase their susceptibility for reprogramming towards a beta cell fate.