The incidence of diabetes is rising worldwide. Using genetic engineering techniques in pigs, scientists at Ludwig-Maximilians-Universität (LMU) in Munich have created a new model of this metabolic disorder, which recapitulates many features of the disease, and promises to contribute significantly to improvements in diagnosis and therapy.
The increasing prevalence of type 2 diabetes places a huge burden on its victims and poses a tremendous challenge to healthcare systems. Half of all heart attacks and stroke cases, but also many other deleterious conditions, can be ascribed to the effects of this metabolic syndrome.
In Germany alone, some seven million people currently suffer from the disease, and the number of cases worldwide is projected to reach 370 million by the year 2030. Type 2 diabetes results from a combination of genetic and environmental factors which cause the organism to become resistant to the action of insulin. This hormone controls the level of glucose in the blood, so insulin resistance leads to a chronic rise in glucose concentrations. A team of LMU researchers led by Professor Eckhard Wolf and Professor Rüdiger Wanke has now introduced a new model system for the study of the disease. They have created a genetically modified strain of pigs that consistently develop the essential symptoms of type 2 diabetes.
"The physiology of the pig is actually very similar to that of humans", says Wolf. "Our model therefore provides a unique tool for the development and testing of new approaches to the diagnosis and therapy of diabetes." After a meal, the concentration of glucose in the blood rises, causing the beta-cells of the pancreas to secrete a correlated amount of insulin. The hormone in turn stimulates uptake of glucose by several tissues, including the skeletal muscles.
In cases of type 2 diabetes, this regulatory circuit is disturbed. Cells exposed to insulin fail to respond, and the consequent failure to remove the glucose causes its level to remain high. This state of chronic hyperglycemia has deleterious effects on many organ systems, leading to cardiovascular disease, kidney failure and blindness, for example. Up until a few decades ago, the disease, which remains incurable, was largely confined to the elderly, but it has since become more and more prevalent among young adults, adolescents and even children. The younger the age of onset, the greater the chance that increasingly severe conditions will develop as time passes.