Technology and Evolution of GLP-1
The Surprising History of GLP-1 Drugs
Written by Dr. Ajay V. Kaduskar, Diabetologist, Nagpur
MD (Medicine), PGDHSc (Diabetology), FEACD (The Netherlands)
Published · 5 min read
Quick answer
GLP-1 stands for glucagon-like peptide-1, a hormone made in the gut after eating. Scientists discovered it in the 1980s and found it helps the pancreas release insulin. Because the natural hormone breaks down in minutes, researchers created longer-acting versions, including one inspired by a hormone in the saliva of the Gila monster lizard. This led to modern medicines such as semaglutide and tirzepatide.
GLP-1 medicines are now in the headlines for diabetes and weight loss. But they did not appear overnight. Their story spans several decades and began with curious scientists studying how the gut talks to the pancreas.
How was the gut-pancreas link found?
In the 1960s, researchers noticed that sugar taken by mouth caused a larger insulin release than the same sugar given through a vein. This difference was called the incretin effect. It suggested that hormones from the gut signal the pancreas to release insulin when food arrives.
How was GLP-1 discovered?
In the 1980s, scientists studying the gene for glucagon found a related fragment, which they named glucagon-like peptide-1. They showed that this hormone, made by gut cells, strongly stimulates insulin release when blood sugar is high. It also reduces glucagon, slows stomach emptying and lowers appetite.
What was the problem with the natural hormone?
Natural GLP-1 is broken down by an enzyme in the blood within a couple of minutes. A medicine based on it could not work for long. This led researchers to look for ways to make a stable version.
Where did the gila monster come in?
In the early 1990s, researchers studying the saliva of the Gila monster, a venomous lizard from North America, found a hormone called exendin-4. It was similar to human GLP-1 but resisted breakdown. This led to the first GLP-1 medicine for diabetes, exenatide, approved in the mid-2000s. It was taken as an injection twice a day.
How did the medicines improve?
Longer-acting versions
Scientists redesigned the molecule so that it lasted longer in the body. This allowed once-daily injections, and later once-weekly injections.
Semaglutide
Semaglutide was designed with a fatty-acid side chain that binds to proteins in the blood, protecting it from breakdown and extending its action. It is available as a weekly injection and as a daily tablet.
Weight-loss discovery
Doctors noticed that people on GLP-1 medicines lost weight, which led to trials in people with obesity. Higher doses were studied specifically for weight management and showed significant results.
Dual agonists
Tirzepatide acts on two gut hormones, GLP-1 and GIP, and showed even greater effects in some trials.
What did researchers learn along the way?
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GLP-1 medicines lower blood sugar with a low risk of hypoglycaemia on their own.
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Some reduce the risk of heart attack and stroke in people with diabetes and heart disease.
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They can protect the kidneys in certain patients.
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They affect appetite centres in the brain.
Why does this history matter?
Knowing the story shows that these medicines are the result of decades of careful research and not a passing fad. It also explains why they are used under medical supervision and why newer versions keep appearing.
When should you see a doctor?
If you are considering a GLP-1 medicine for diabetes or weight, speak to a diabetologist first to check whether it is suitable and safe for you.
A quick recap
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GLP-1 is a gut hormone that helps control blood sugar and appetite.
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Scientists found it in the 1980s, and its short life in the body was a problem.
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A hormone in Gila monster saliva inspired the first long-acting version.
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Semaglutide and tirzepatide are the result of decades of improvement.
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These medicines should be started only with medical guidance.
The path from a lizard's saliva to modern medicine shows how patient science can change lives. To learn whether this class of medicines is right for you, consult Dr. Ajay V. Kaduskar, a diabetologist at Niramay Clinics in Nagpur.
Sources and further reading
Frequently asked questions
Several scientists contributed. In the 1980s, researchers studying the glucagon gene identified GLP-1 and showed that it stimulates insulin release. Later work turned this knowledge into medicines.
A hormone in the saliva of the Gila monster, called exendin-4, resembles GLP-1 but lasts longer. It led to the first GLP-1 medicine for diabetes, exenatide.
The first GLP-1 medicine for type 2 diabetes was approved in the mid-2000s. Longer-acting and weekly versions followed, and weight-management doses came later.
Semaglutide is modified to resist breakdown and stay in the body for about a week, while natural GLP-1 lasts only minutes. This allows weekly dosing.
Because they lower blood sugar by increasing insulin release when sugar is high. Their effect on appetite and weight was noticed later, leading to trials for obesity.
Both are gut hormones that help release insulin after eating. Tirzepatide acts on both, which may explain its stronger effect on weight and blood sugar in studies.
Related reading
- Full guide: GLP-1 drugs
- How GLP-1 Injection Pens Work: The Technology
- Oral GLP-1 Tablets: Are Pills Replacing Injections?
- Dual and Triple Agonists: What Comes After Semaglutide?
- Why Did GLP-1 Medicines Become a Global Trend?
If you would like advice suited to your own reports and medicines, you can book an appointment or visit Niramay Clinics in Dhantoli, Nagpur.
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