Dr. Schaffer's laboratory has been studying the effects of diabetes on heart function. Many of the molecular consequences of diabetes, such as altered osmotic balance, reduced protein synthesis, impaired energy metabolism and abnormal ion transport, are duplicated by incubation of isolated myocytes with high concentrations of glucose. Although glycosylation may play a role in the development of these abnormalities, osmotic imbalance also appears to be a contributing factor. The aim of more recent studies has been to clarify the basis of another property of the diabetic heart, the resistance to ischemic or hypoxic injury. This property is also duplicated by either chronically exposing myocytes to hyperosmotic medium or depleting the cell of an important organic osmolyte, taurine. Of particular interest are the effects of high glucose and osmotic stress on hypoxic-induced apoptosis. The information obtained will provide important insights into the regulation of programmed cell death in the heart.
