The History Of Insulin From 1920 To 2008
For thousands of years becoming a diabetic was a death sentence and
this may still have been the case today if Dr. Frederick Banting had
not discovered the usefulness of Insulin;
before this the only way to control diabetes was through a diet that
was extremely low in carbohydrates and sugar and high in fat and protein;
most diabetics on this type of diet lived for about a year, if they
didn't starve to death first.
Back in 1889 scientists Oskar Minkowski and Josef von Mering discovered
by chance, whilst studying the metabolism of fat, that removing a dog's
pancreas caused diabetes in the animal; further research suggested that
the pancreas had at least two functions, to produce digestive juices
and to secrete a substance that regulated blood sugar.
In 1869 Paul Langerhans discovered that within the pancreatic tissue
that produced digestive juices, there were clusters of cells whos function
was unknown and in 1893 Gustav Laguess suggested that these cells, which
he named the Islets of Langerhans, produce the glucose regulating substance
later known as Insulin.
Then back in October 1920 the Canadian Surgeon Frederick Banting started
work on a idea that could possibly explain why people die from diabetes;
he thought that in diabetics the pancreatic juices were destroying one
of the substances that were being produced by the islets of Langerhans.
Banting wanted to stop the pancreas from working but keep the islets
of Langerhans working in order to locate the elusive substance and in
1921, with the help of Charles Best and 10 dogs, they surgically stopped
the flow of nourishment to each of the dog's pancreas by tying up the
pancreatic ducts, to stop them creating digestive juices; they left
them this way for several weeks, this act destroyed the digestive cells
and left thousands of pancreatic islets; this approach, which would
now be considered barbaric, was successful because even though the pancreatic
islets produce other hormones like glucagon and somatostatin, they are
not produced in the same quantities as Insulin.
They later removed the pancreas from each dog, chopped them up and froze
them in a saline mixture; when they were half frozen the pancreas pieces
were ground up and filtered; they named this pancreatic extract isletin;
they then injected some isletin into one of the dogs, which now had
diabetes, due to having had its pancreas removed and the dog's blood
glucose level dropped and it became healthier and stronger; the dog
was given several injections a day and remained free of diabetic symptoms;
this experiment was carried out on the other dogs and all of the results
were the same apart from problems caused by the purity of the mixture;
they had discovered and successfully administered Insulin.
Shortly after this success, several researchers, including James Collip,
from the same lab worked on the purification and production of isletin
for human diabetics and they renamed it Insulin from the latin word
'insula' meaning island;
First Human Test
By late 1921, the team had conclusively proved that diabetes was a condition
brought on by insulin deficiency and it was time to test the new substance,
that they had derived from a cow’s pancreas, on humans, and so in 1922
the first Insulin tests were carried out on Leonard Thompson, a 14 year
old diagnosed with Type 1 diabetes in 1919.
The health of the test subject a Mr. Leonard Thompson improved on a
daily basis meaning the tests were successful and the Insulin extract
worked; however, the discovery and use of Insulin is not a cure for
diabetes; though, it did give immediate hope to many seriously ill diabetics
and still does, enabling those with diabetes to lead fairly normal lives
instead of dying shortly after being diagnosed.
In 1923, Banting and Macleod were jointly awarded the Nobel prize for
Medicine; Banting, however, felt that the prize should have been shared
between himself and Best, so he gave credit to his assistant by sharing
his cash reward with him; Macleod did the same with Collip; Banting
and his team patented their insulin extract, but gave away all rights
to the University of Toronto, which later used the income to fund further
research into insulin; soon after, medical firm Eli Lilly began large
scale production of the extract.
While Best continued to have a successful career, Banting’s life was
cut tragically short when he died in a plane crash at the age of 41;
but his legacy lives on, and millions of people with diabetes worldwide
continue to live long and healthy lives as a result of his team’s discovery.
In 1963, researchers managed to produce insulin chemically in a laboratory,
but they could not make enough of it, for it to be viable; at that time,
insulin was still extracted from pigs and cattle and though animal insulin
worked well, it was not an exact match with the human hormone and sometimes
caused adverse reactions, such as skin rashes.
In 1977, researchers succeeded in manufacturing human insulin, by inserting
the genes that code for human insulin into bacteria and yeast cells;
this allowed its production on a much bigger scale; the resulting commercial
product, brand named Humulin, revolutionised the treatment of diabetes
as it caused fewer side effects.
Since then the production and supply of Insulin has been greatly improved
and high quality Insulin is now available to all diabetics in civilised
countries; the first Insulin preparations, known as bovine and porcine
Insulin, came from the pancreases of slaughtered cows and pigs, which
was purified, bottled and sold and works very well for the majority
of diabetics; today human and synthetic Insulins, which are genetically
engineered and structurally identical to that made by a functioning
human pancreas are also used.
Diabetes Related Information Leaflets
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