Islet Cell Biology and Physiology

Cells contained within the islets of Langerhans region of the pancreas – islet cells - play a major role in metabolism and health.  Even though these specialized cells make up only a small portion of the pancreas, their function is of profound importance.  The β-type islet cells produce insulin, the hormone needed to assimilate blood glucose into cells throughout the body.  Other types of islet cells in the pancreas perform other functions related to glucose balance, and a large portion of the pancreas is related to entirely different functions altogether.  But islet cells, particularly β-cells, have a major influence on nutrient metabolism and well-being.

The viability of β-cells is central to many forms of diabetes.  Type 1 diabetes (T1D) is a consequence of an outright loss of β-cell functionality resulting from autoimmune disease, and a subsequent loss of insulin production.  The first treatment for T1D was insulin replacement, made possible by Banting and Best’s discovery of insulin, and by the first clinical application of insulin therapy made by the University of Alberta’s Dr. James Collip.  But even with exogenous insulin replacement, Type 1 diabetes patients are still in a constant struggle to maintain glucose balance, suffering numerous secondary health complications as a result.  In recent years islet cell replacement therapy has offered new hope for Type 1 diabetes patients.  The Edmonton Protocol, the islet cell transplant procedure developed by ADI scientists and adopted around the world, can eliminate or alleviate the need for exogenous insulin injections and improve gylcemic control.  Type 2 diabetes (T2D) is an increasingly prevalent form of the disease that is often related to insufficient insulin production or secretion by β-cells, which in turn can be the result of numerous risk factors that include weight, genetics, lifestyle, and nutrition.  In either T1D or T2D then, islet cell function is central to the disease.             

Islet studies at ADI help guide the prevention and treatment of diabetes.  By examining islet cells at the microscopic level, ADI scientists learn the structures and processes that govern the production and secretion of insulin.  This includes the processes associated with polarization/deploarization, receptor-ligand interactions, membrane channel variations, genetics and intracellular signalling and secretory pathways.   In addition, researchers are establishing the influence of neurological and extracellular signalling on islet function, as well as the interplay between nutrition and islets.   As ADI scientists compare these processes in normal and dysfunctional cells using advanced equipment and techniques, it is becoming clearer what specific aspects are related to diabetes.  This presents exciting opportunities to protect or treat afflicted cells with therapeutic measures – possible because the cellular targets for intervention are known.  Research is also being conducted to improve the Edmonton Protocol by improving the stability of transplanted cells while reducing the complications associated with surgery.   Research at ADI is also developing ways to increase the supply of islets that exist for both research and transplantation. 

If you are interested in pursuing research in the area of Islet Studies at the ADI, please contact Dr. Peter Light at peter.light@ualberta.ca or Dr. Patrick MacDonald at patrick.macdonald@ualberta.ca