Despite the pandemic, 2021 is a year to celebrate, as it marks the centenary of one of the most important breakthroughs in the history of medicine — the discovery of insulin in 1921 at the University of Toronto, Canada.
The discovery is so dramatic that several movies have been made of it. The principal actor in the drama is Fredrick G. Banting, whose name is synonymous with it. His birthday, November 14, is celebrated as World Diabetes Day.
Banting completed his medical studies at the University of Toronto in December 1916, but as the First World War was on, he was soon drafted into the Army. He was wounded in the Battle of Cambrai in 1918, but he continued to attend to other wounded soldiers, and for this, he was awarded the Military Cross. This shows his stoicism, a trait which would help him later in life. He returned to Canada and went on to do surgical training and studied orthopaedics. As his private practice was not successful, he started teaching medical students at the University of Western Ontario.
A startling dream
One night, tired, he went to sleep after reading an article on pancreas by Moses Barron. At 2 a.m., he was awakened by a dream which led him to understand that tying the pancreatic duct by a ligature would cause degeneration of the cells of the pancreas concerned with digestion, but leave the islets of Langerhans intact. Banting had a sudden realisation that if there was a hormone in these islets which reduces sugar, it could be extracted and used to treat diabetes, and this became an obsession with him.
He approached J.J.R. Macleod, Professor of Physiology at the University of Toronto, with a request to allow him to carry out experiments to isolate this hormone. Initially, Macleod was reluctant because many famous scientists like Naunyn, Minkowski and Mering, Opie, Sharpey-Schafer and Nicholas Paulesco had failed.
Macleod finally provided Banting the laboratory facilities, a few dogs to experiment with and also a student, Charles Best, as his assistant. Macleod gave them a few weeks to complete their experiments, while he went on a holiday to Scotland.
Summer triumph
The story of how Banting and Best struggled through the summer of May 1921 (one of the hottest summers at that time) with no air conditioning and with crude equipment makes very interesting reading. Experiment after experiment failed and dog after dog died. Banting had to surreptitiously procure dogs from the streets of Toronto. Being a surgeon, he carried out the surgeries, while Best measured the blood glucose levels of the dogs. When the pancreas was removed, it made the dogs severely diabetic.
From the pancreas, Banting and Best tried to extract the mysterious internal secretion and then injected it into diabetic dogs to see whether their blood glucose levels would decrease. After a series of failures, one day in July 1921, history was made when they found that the blood glucose of a dog started coming down.
Macleod came back from his holiday, and though initially did not believe the results, he soon got convinced that there was indeed a hormone in the islets of Langerhans that reduced the glucose levels. Banting suggested the name isletin, but Macleod convinced him that the name insulin was better because it comes from the Latin word Insula meaning island, a name suggested years earlier by Sharpey-Shafer.
Human clinical trials started in January 1922 and Leonard Thompson, a 14-year-old boy who was dying from uncontrolled diabetes, was one of the first recipients. He responded dramatically. The initial clinical trials were, however, not very successful, because of the crude nature of the extracts prepared by Banting and Best.
A biochemist from Edmonton, James Collip, who had been brought on board, helped to purify the insulin. This helped prevent adverse reactions such as fever and abscess formation at the injection site. Soon, the lives of dozens of children who were dying of diabetes were saved after the insulin injections were administered. One of the greatest breakthroughs of modern medicine had been achieved!
The University of Toronto licensed the production of insulin to Eli Lilly & Co. in the U.S. which, within a year, were able to mass-produce insulin.
Till 1921, the lifespan of a child affected with Type 1 diabetes varied from three months to a maximum of two or three years. The latter was only possible if extreme starvation diets were given which barely kept the children alive until they died of diabetic coma. With the discovery of insulin, all that changed forever, and children with Type 1 diabetes were saved from death.
Indeed, the discovery of insulin led to the Nobel Prize for Medicine being awarded in 1923, barely a year after the first clinical trials of insulin were done. This is a record of sorts in the annals of the Nobel Prize. However, the prize itself was steeped in controversy. The Nobel committee awarded the prize to Banting and Macleod. Banting alleged that Macleod had nothing to do with the discovery, and insisted that it was Charles Best who deserved it and he therefore shared his part of the prize money with Best. Not to be outdone, Macleod stated that it was Collip’s purification of insulin which led to the large-scale use of insulin and hence he shared his prize money with Collip. So finally, there was glory enough for all the four co-discoverers of insulins: Banting, Best, Macleod and Collip.
Insulin soon became commercially available in most countries. Canada, the U.S., the U.K. and Europe were the early users. India, being under British rule at the time, also soon got insulin. The big question was whether insulin being a protein, would work in a hot tropical country. Several papers were published from India in the 1920s which showed that if insulin was kept in the refrigerator, it would not lose its potency.
Today, a hundred years after the discovery of insulin, there are recorded instances of children with Type 1 diabetes who have lived for 80 to 90 years. I know of several people with Type 1 diabetes in India who are alive 60 years after they first started taking insulin injections. For children with Type 1 diabetes, there is, indeed, no other treatment other than insulin injections.
Still out of reach
If the discoverers of insulin were alive today, they will, probably, be unhappy. It is a sad fact that even 100 years after its discovery, lives of children with Type 1 diabetes are still being lost due to several factors. First, despite enough global supplies of insulin, its accessibility still remains an issue in many developing countries. Second, it is still unaffordable not only to people in developing countries but even in some developed countries, even the U.S.
As we celebrate the centenary of insulin’s discovery, it is my dream that not a single one of the 1.5 lakh children with Type 1 diabetes in our country dies because of lack of affordability, or accessibility, to insulin.
I was privileged to be part of the World Health Organization’s “Global Diabetes Compaq”, a white paper produced in connection with the insulin centenary, which was sent to all its member countries. One of the fundamental aspirations spelt out to governments in this report, is that every person with Type 1 diabetes in the world should have access to insulin.
Indeed, insulin should be made a fundamental right of all human beings just like food, water or clothing. If this happens (and I do hope it does, and soon), that would be the best way for us to celebrate the epoch-making discovery made by Banting and colleagues in the summer of 1921.
( The author is the chairman of Dr. Mohan’s Diabetes Specialities Centre, Chennai )
drmohans@diabetes.ind.in
