Diabetes, a chronic disease that affects millions of people around the world and occurs when the body cannot produce enough insulin or use it effectively, was definitively fatal before the discovery of the insulin drug.
People with diabetes had to follow strict diets that often led to hunger and malnutrition. Because there was no effective treatment, many people with diabetes died within a few years of being diagnosed. However, everything changed after a group of researchers worked 100 years ago.
How did scientists discover insulin?
Insulin is a hormone that helps cells absorb glucose from the bloodstream and use it for energy. Without insulin, glucose builds up in the blood, causing high blood sugar levels and various complications.
The link between diabetes and the pancreas was first established in the late 19th century by German researchers Oskar Minkowski and Joseph von Mering. They found that removing the pancreas from dogs caused diabetes, suggesting that the organ produces something that regulates blood sugar levels.
But isolating this substance turned out to be very difficult. Many scientists have tried to extract pancreatic juices or tissue and inject them into diabetic animals or humans, but none have been successful. The pancreatic extracts were too toxic, too impure, or too unstable to have any effect.
In fact, we owe insulin medicine to our dear friends, dogs.
The invention came about in 1921 when a young surgeon named Frederick Banting proposed an idea to John Macleod, professor of physiology at the University of Toronto. Banting suggested connecting dogs’ pancreatic ducts to stop the flow of digestive enzymes that destroy insulin-producing cells. He hoped this would allow him to get a stronger output from the degenerated pancreas.
Macleod was skeptical, but agreed to give Banting a small lab space and a few dogs to test his hypothesis. He also appointed him a medical student named Charles Best as his assistant.
Banting and Best conducted several experiments on dogs together in the summer of 1921. They were able to produce a crude extract from blunted pancreas and inject it into diabetic dogs, lowering blood sugar levels and prolonging their survival.
The first human injection was not as successful as expected.
Encouraged by these results, Banting and Best developed a method of extracting insulin from the pancreas, producing a purer output, which they called “isletin,” and then tested it on a human patient for the first time.
The patient was Leonard Thompson, a 14-year-old boy who was dying of diabetes at Toronto General Hospital. He made the first islet injection on January 11, 1922. The injection caused an allergic reaction and had little effect on blood sugar levels.
But Banting and Best did not give up. They collaborated with James Collip, a biochemist who improved their purification process and produced a more potent extract, which they renamed “insulin.” On January 23, 1922, Leonard Thompson received his second injection of insulin. This time her blood sugar levels dropped significantly and her symptoms improved significantly. He was the first to be successfully treated with insulin.
A sweet anecdote: the hospital full of children awaiting death turns into a nest of joy filled with hope.
In 1922, after the discovery of insulin was fully completed and its application on patients, a group of scientists went to Toronto Hospital. More than 50 children with diabetes were receiving ‘treatment’ in this hospital.
But many were in coma and dying from diabetic keto-acidosis. Those who were not in a coma were placed on a strict diet, which inevitably resulted in death. It was hoped this would cure them.
These dying children were saved by a group of scientists who came to the hospital with an insulin vaccine. Scientists have begun injecting this freshly discovered purified insulin extract into children.
Of course, the treatment process was not short-lived, it was a period of 4 months. However, while the last child was given insulin, the first children who were vaccinated began to wake up slowly. Then the children who were in a coma woke up. Those who were not in a coma fully recovered. This hospital, shrouded in death and gloom, suddenly turned into a house overflowing with joy and hope.
However, this success brought with it great ethical debates.
News of the discovery of insulin spread rapidly around the world, and Banting and his colleagues were hailed as heroes. They were awarded the Nobel Prize in Physiology/Medicine in 1923, just two years after their initial discovery. However, their success came with some controversies and challenges.
One of the biggest controversies was the use of animals in insulin research. Banting and Best conducted their experiments on dogs, and many other scientists continued to use animals for insulin production and testing. Animal rights activists have criticized these practices, arguing that they cause unnecessary suffering and that alternatives such as cell culture or synthetic insulin should be explored.
Another controversy was the patent rights on insulin. Banting and his team sold the insulin’s patent to the University of Toronto for just $1, believing the insulin would be widely available and affordable. But the university later sold its rights to pharmaceutical companies, which monopolized the insulin market and set high prices, making it difficult for many patients to access insulin.
Despite these challenges, insulin has continued to save countless lives and inspire further research. Scientists have discovered different types of insulin, such as rapid-acting, long-acting, and combination insulin, to suit different patient needs. They’ve also developed insulin pumps, continuous glucose monitors, and other devices to help people with diabetes manage their condition more effectively.
Although controversial, insulin is one of the greatest discoveries in the history of medicine.
Today, insulin remains a critical treatment for people with diabetes, along with diet, exercise, and other medications. According to the International Diabetes Federation, approximately 463 million adults aged 20-79 years worldwide have diabetes, and this number is expected to reach 700 million by 2045. Insulin research and innovation continues, with the ultimate goal of finding a cure for diabetes.
The discovery of insulin marked a turning point in the history of medicine and marked the first time that a chronic and deadly disease could be treated with a drug. This was the result of the curiosity, creativity, and collaboration of various groups of researchers, who overcame many obstacles and challenges to make insulin a reality.
Insulin not only changed the lives of people with diabetes, but also opened up new avenues of research and innovation in the fields of endocrinology, biochemistry, pharmacology and biotechnology. Let’s end our article with the words of Frederick Banting:
“Insulin belongs to the world, not me.”