In this article, we will know everything there is to know about how insulin came about – its history on how it was first used to treat diabetes, types and the evolution of insulin to where we stand currently in the insulin market.
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How was diabetes treated before insulin was discovered?
Insulin was discovered in the year 1921, before which people with diabetes were treated only by recommending a low-carbohydrate or a low-caloric diet so much so that patients also died of starving themselves by following the prescribed diets.
A series of events that led to the discovery of insulin
1889 – Oskar Minkowski and Joseph Von Mering were German researchers who removed the pancreas in dogs and observed that they developed diabetes and died soon after. This led to the understanding and discovery of the link between diabetes and “pancreatic substances” (later known to be insulin) that cause diabetes with their deficiency.
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1910 – Sir Edward Albert Sharpey-Shafer suggested that a single chemical in pancreas was absent in people with diabetes. He named this chemical ‘insulin’ derived from the Latin word ‘insula’ meaning island.
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1921 – Frederick Banting, a surgeon along with his assistant Charles Best, figured out how insulin can be extracted from the pancreas of a dog and called it ‘thick brown muck’ unaware that this substance would later be used to save people’s lives by treating diabetes. With the help of their colleagues J.B Collip and John Macleod developed a cleaner and pure form of insulin.
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1922 – The first patient to be administered with insulin was Leonard Thompson, who was a 14 year old boy on the deathbed from suffering with diabetes in Toronto. Leonard was the first person to be injected with insulin after which his fatally high blood glucose levels dropped to close to normal blood glucose levels.
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1923 – Frederick Banting and John Macleod became recipients of the Nobel prize in medicine, which was shared with Charles Best and J.B. Collip for the discovery of insulin.
Evolution of insulin treatment
Isolation – Insulin was isolated and discovered from the pancreas of a dog and the correlation between the cause of diabetes as insulin deficiency was identified.
Insulin from animals – Insulin was extracted from cows which was first used to treat diabetes type 1.This form of insulin was later found to be impure and rejected by the human body due to the alien proteins associated from cows and pigs.
Emergence of NPH insulin – NPH or Neutral Protamine Hagedron which comprises a mixture of insulin, zinc and protamine. Protamine was a protein extracted from fish sperm which reduced the solubility of insulin and made it more lasting.
Insulin is a synthetic form – Post the prevalent use of insulin as an animal protein, humulin or human insulin became the first ever form of insulin to ever be synthesized.
Analogs of Insulin – These are structurally very similar to the human insulin but don’t completely match the insulin function within the human body due to their altered human structure.
Analogs of insulin with fast action – For getting a faster reaction, the analogs of insulin are substituted by certain specific amino acids that regulate the binding of insulin to the receptors in the cells.
Insulin Analogs with long action – In these analogs along with protein substitutions for faster binding, chemical groups are also added to reduce or slow down the absorption of insulin thus, resulting in a slower or long-lasting reaction. Known examples of Long – acting insulin analogs include – Levemir, Lantus and Tresiba.
Insulin that is non-injectable – Since, insulin is a form of a protein, it can’t be administered orally since it will get digested. Although research on developing a type of insulin which sustains the effect of acid in our stomach and saving itself from digestion is being done. A type of insulin which can be inhaled through an aerosol inhaler for being a powdered form of insulin is being developed. One such non-injectables in the market is Afrezza.
Now that we have understood the evolution of insulin, let us look at the types of insulin existing in the market currently:
Based on the action or peak-time:
- Rapid action insulin: Administered at the time of meal time and the types of rapid action insulin classified based on their peak time include:
- Aspart – peaks at 10 – 20 minutes of consumption
- Lispro – peaks at 15 – 30 minutes of consumption
- Glulisine – peaks at 20 – 30 minutes of consumption
- Short – acting insulin: The oldest type of insulin which lasts up to 4 – 12 hours.
- Regular insulin (Trade name – Humulin, Novolin) – 30 – 60 minutes.
- Intermediate acting insulin (last for 12 hours): NPF peaks at 1-2 hours
- Long – acting insulin (last for the longest at 24 hours): Newest type of insulin
- Levemir type peaks at 60 – 90 minutes
- Lantus has no peak time
Novel insulins – Latest type of insulins or inventions in the insulin market.
- Ultra long acting insulin – Glargine modified insulin lasts for up to 36 hours.
- Inhalational insulins – These were not successful and did not stay in the market.
Although over-time insulin has undergone modifications through innovation to suit the fast-paced modern world and cater to the increasing demographic of people who fall prey to diabetes. Insulin continues to be the saviour in regulating and improving the quality of life of patients suffering with diabetes. Consult a diabetes specialist today to know more on the type of insulins in the market and the one best suited for your needs and treatment.