John J. R. MacLeod (1876–1936), Frederick G. Banting (1891–1941), James B. Collip (1892–1965), Charles H. Best (1899–1978), Frederick Sanger (b. 1918)
The basic details surrounding the discovery of insulin and its impact on the treatment of diabetes are widely accepted. To whom credit should be bestowed remains a subject of controversy.
Descriptions of patients experiencing extreme thirst and copious urination date back thousands of years, and in the first century, this condition was termed diabetes (Greek for siphon). In the 1670s, the diabetic’s urine was found to contain sugar, and in 1889, the pancreas’s role in the disease was identified.
Canadian surgeon Frederick Banting persuaded University of Toronto professor of physiology John J. R. MacLeod to let him use McLeod’s laboratory and ten dogs in 1921, while the professor was vacationing. Banting enlisted the assistance of Charles Best, who was waiting to enter medical school. They extracted the sugar-lowering principle from one dog’s pancreas and then administered it to and successfully treated another severely diabetic dog. After returning, MacLeod offered Banting some helpful advice, extended his time in the lab, and paid him a modest salary.
Within months, in early 1922, injections of this same extract saved the life of fourteen-year-old diabetic Leonard Thompson. Chemist James Collip helped to improve extraction and purification techniques, and several dozen children were successfully treated shortly thereafter. In record time, the 1923 Nobel Prize in Physiology or Medicine was awarded to Banting and MacLeod, but Best was conspicuously overlooked. Banting rightly viewed this oversight as a travesty and split half his prize money with Best. McLeod, in turn, shared his award with Collip. That year, Eli Lilly began the commercial production of insulin. To control the blood-sugar levels of diabetics, there are four basic types of insulin, which differ based on how rapidly they start and stop working.
Less controversial was the granting of the 1958 Nobel Prize in Chemistry to Frederick Sanger for determining the amino acid sequence of the insulin molecule. Insulin’s importance transcends diabetes. This use of estrogen to alleviate the symptoms of menopause is called hormone replacement therapy, a concept developed with the use of insulin to replace a deficient hormone in diabetics.
SEE ALSO Insulin Shock Therapy (1927), Premarin (1941), Human Insulin (1982).
A high-power microscopic view of an islet of Langerhans. These islets, which number about one million in a healthy adult pancreas, are responsible for the production of insulin. In type 1 diabetes, an autoimmune process selectively destroys the islets.