60 Fun Facts About Insulin

Which islet cell type produces insulin?

Their neighbours, the alpha cells, secrete the opposing hormone glucagon.

From which Latin word does the name 'insulin' derive?

The name refers to the islets of tissue that make it.

What effect does insulin have on blood glucose?

It promotes glucose uptake into liver, fat and muscle cells, where it becomes glycogen or fat.

Which hormone from the alpha cells raises blood glucose, the opposite of insulin?

It triggers the liver to break down glycogen and make new glucose.

How many amino acids make up the human insulin protein?

They form an A-chain and a B-chain linked by disulfide bonds.

What destroys the insulin-producing cells in type 1 diabetes?

In type 2 the beta cells decline for other reasons and tissues become insulin resistant.

Which animal's insulin is closest to human insulin and long treated diabetics?

Cattle insulin was also widely used before biosynthetic human insulin arrived.

Which Berlin medical student identified the pancreas's 'little heaps of cells' in 1869?

The islets that bear his name make insulin; their function was unknown to him.

What did Minkowski and von Mering find in 1889 after removing a healthy dog's pancreas?

It was the first proof of a link between the pancreas and diabetes.

Who coined the word 'insulin' in 1916 for a then-hypothetical islet hormone?

Jean de Meyer had proposed the near-identical 'insuline' in 1909.

Which Romanian physiologist normalised a diabetic dog's blood sugar with an extract in 1916?

Many argue he deserved a share of the 1923 Nobel Prize.

What structure do most insulins form that delays their entry into the blood?

Rapid-acting analogues are engineered not to, so they act within minutes.

How was Charles Best chosen over Clark Noble as Banting's assistant in 1921?

Banting kept him all summer and later shared his Nobel money with him.

What did Banting propose tying off in dogs so the pancreas would atrophy, sparing the islets?

He jotted the idea down in October 1920 after reading about duct blockages.

By how much did the first extract, 'isletin', cut a diabetic dog's blood sugar in an hour?

Macleod insisted the experiment be repeated with more dogs and better equipment.

From which animals did Banting take pancreases to skip the weeks of duct-tying?

Their pancreases had not yet developed digestive glands; adult cow pancreas followed.

Which biochemist purified the extract enough for human use in January 1922?

Banting and Best regarded him as an interloper and he soon left the project.

Who received the first insulin injection, at Toronto General Hospital on 11 January 1922?

The impure first dose caused an allergic reaction; a refined dose 12 days later worked.

Elizabeth Hughes, an early American insulin patient, was the daughter of which official?

Charles Evans Hughes later became Chief Justice.

Which drug company began mass-producing insulin with the Toronto team in 1922?

Its chemist George Walden used isoelectric precipitation to refine it.

For how much was the insulin patent assigned to the University of Toronto in 1923?

The aim was to stop anyone else securing a profitable monopoly.

Which public health lab brokered the 1922 non-patent agreement among the discoverers?

Its director John FitzGerald acted as peacemaker.

Which two men were awarded the 1923 Nobel Prize in Physiology or Medicine for insulin?

Banting, furious that Best was left out, split his money with him; Macleod split his with Collip.

Which American physician pinned diabetes on damage to the pancreatic islets in 1901?

Zuelzer, Scott and Kleiner all then tried and failed to isolate the islets' secretion.

Who first produced insulin in crystallised form, in 1926?

Its protein nature was fully proven when amino acids were isolated from it in 1935.

Which British biochemist sequenced insulin's amino acids, winning the 1958 chemistry Nobel?

He later won a second chemistry Nobel for DNA sequencing.

In whose laboratory was insulin's complete 3-D structure solved in 1969?

She had won the 1964 chemistry Nobel for crystallography.

Who won the 1977 Nobel Prize for developing the radioimmunoassay for insulin?

She was only the second woman to win the medicine prize.

Researchers from which country achieved synthetic crystalline bovine insulin in 1965?

Labs in Pittsburgh and Aachen made the first synthetic insulin around the same time.

In which bacterium was the first recombinant human insulin produced in 1978?

Riggs and Itakura at City of Hope worked with Herbert Boyer of Genentech.

Under what brand name was the first biosynthetic human insulin sold in 1982?

Genentech developed it and Eli Lilly marketed it.

Besides E. coli, which organism is commonly used to make recombinant insulin?

Novo Nordisk developed a yeast process independently.

Which plant have Canadian researchers used to make cheaper recombinant insulin?

Almost all insulin used worldwide is recombinant human insulin or its analogues.

Which three insulin analogues are rapid-acting, working within 5 to 15 minutes?

Long-acting glargine and detemir last about 24 hours without major peaks.

How was a unit of insulin first defined in 1922?

It depended on the size and diet of the rabbits.

What is the most common serious side effect of insulin treatment?

Allergic reactions are usually to preservatives such as zinc or meta-cresol.

Since January 2006, what kind of insulin has been distributed in the US?

Animal insulin now needs a special FDA import process.

How is insulin usually administered?

Syringes, pens and pumps all deliver it subcutaneously.

Which Austrian psychiatrist introduced insulin coma therapy in 1927?

Patients, mostly diagnosed with schizophrenia, were put into daily comas for weeks.

How was Arnold Kadish's 1960s prototype insulin pump worn?

It worked but was too bulky and complicated to sell.

Frederick Banting's birthday, 14 November, is marked each year as what?

The IDF and WHO created it in 1991.

How did Frederick Banting die in 1941?

Both engines of the Lockheed Hudson failed after take-off from Gander.

Apart from medicine, what was Banting known for in Canada?

His works are seen as part of the Group of Seven's Jackson circle.

Near which Ontario town was Banting born on a farm in 1891?

The local high school is now named after him.

Which diabetic Nobel laureate lived, thanks to insulin, to find a pernicious anaemia cure?

William Castle noted that insulin was thus indirectly responsible for that cure too.

What is unusual about the two Nobel Prizes won by the man who sequenced insulin?

John Bardeen in physics and Barry Sharpless in chemistry are the others.

Insulin's two chains, A and B, are held together by what kind of chemical bond?

The mature hormone has a molecular mass of 5,808 daltons and was the first peptide hormone discovered.

Bovine insulin differs from human insulin in how many amino acid residues?

Porcine insulin differs by only one, and even some fish insulins work clinically in humans.

How many amino acids long is preproinsulin, the inactive precursor from which insulin is made?

Its signal peptide is snipped off in the rough endoplasmic reticulum to leave proinsulin.

Which metal ions sit at the centre of the stable insulin hexamer stored in beta cells?

The hexamer, about 36,000 daltons, is inactive; the working form of the hormone is the monomer.

Which glucose transporter does insulin insert into the membranes of muscle and fat cells?

This is how the hormone drives glucose out of the blood and into tissues.

Who discovered preproinsulin in 1974 while a research fellow at UCLA?

He had spent the previous year learning to isolate and translate messenger RNA, using pancreases from a Los Angeles slaughterhouse.

In which year did the WHO add insulin to its model list of essential medicines?

Insulin is usually injected under the skin, by syringe, pen or pump, and an inhaled form is sold in the US.

Which hormone released under stress strongly inhibits insulin release, raising blood glucose?

Cortisol, glucagon and growth hormone also oppose insulin's actions in stressful times.

Which two Pittsburgh and Aachen chemists first synthesised insulin in the mid-1960s?

Chinese researchers achieved synthetic crystalline bovine insulin around the same time, in 1965.

Which two organs are the main sites where insulin is cleared from the body?

The liver removes most insulin on its first pass, so most endogenous insulin never gets past it.

Roughly how long does the rapid first phase of insulin release from beta cells last?

A slower second phase then peaks at two to three hours as newly formed vesicles are released.

Insulin release from the pancreas after a meal oscillates with roughly what period?

The pulsing is thought to stop insulin receptors on target cells from being down-regulated.

Reduced levels of insulin-related proteins made inside the brain are linked to which condition?

Once in the brain, insulin also enhances learning and memory, particularly verbal memory.

Which Genentech co-founder collaborated on the first recombinant human insulin in 1978?

Arthur Riggs and Keiichi Itakura did the work at the City of Hope's Beckman Research Institute.