Large Molecules - Biotechnology and Your Health: Pharmaceutical Applications - page 40

they have too little growth hormone . Growth hormone is a protein
produced by the pituitary gland, located at the base of the brain
(Figure 3.2). Growth hormone influences the development of
The Discovery of Insulin: A Lifesaver
Imagine your doctor tasting your urine to find out what was making you constantly thirsty
and hungry and wasting away to skin and bones! For hundreds of years, this was a fairly
common practice. Diabetes had been known for centuries, and one advance came when
physicians realized that patients with diabetic symptoms often had high levels of sugar
in their urine. In the 11 th century, someone took a sip of the urine and the condition was
named diabetes mellitus (from the Latin word for “honey” or “sweet”).
Until the 1920s, other than ordering a very restricted diet with little carbohydrates
or sugar and lots of fat and protein, the physician could do little or nothing to prevent
the death of a diabetic patient within a few months or years. In 1920, Frederick Banting,
a young physician on the staff of Western University in London, Ontario, Canada, read
about a recent study that had shown that diabetes develops only when distinctive cells
in the pancreas, called the islets of Langerhans , were damaged. Banting became
determined to isolate or purify the substance found in the islets of Langerhans and
test it to see whether diabetes could be reversed. In the spring of 1921, he was given
some laboratory space and hired an assistant named Charles Best. Working over a hot
summer and without salaries, Banting and Best removed the pancreas of dogs to cause
diabetes, then reversed the condition by giving the newly diabetic dogs fluid from the
islets of Langerhans of healthy dogs. With this initial success, they won the support of
J.J.R. MacLeod of the University of Toronto and a biochemist named J. B. Collip. They
switched to using islets of Langerhans from slaughterhouse calves, and had further
success in dog experiments with the extracts and subsequently with concentrated mate-
rial they called iseltin, because it was obtained from islet cells. Other researchers
had worked to purify the active material from calf pancreas, and the name “insulin”
had been proposed as early as 1906. In 1922, a teenager in a diabetic coma became
the first human to receive an injection of insulin. His condition improved with the
injections. When reports of his treatment spread, the challenge became to produce
enough insulin to treat all the diabetics who wanted it. By 1923, insulin was widely
available. In February of that year, Banting and MacLeod were awarded the Nobel Prize
in Physiology or Medicine.