Quote · The Peter Attia Drive
#401 ‒ How curiosity transforms medicine: extraordinary discoveries that changed modern healthcare
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The discovery of GLP-1 receptor agonists: from Gila monster venom to a new era in metabolic medicine
At 54:10 · chapter starts 47:30
In the late 1980s, clinical endocrinologist John Eng was seeing veterans with diabetes at the Bronx VA Medical Center and moonlighting in Rosalind Yalow's lab, which had developed uniquely sensitive peptide hormone assays using radioimmunoassay technology. Eng had read that Gila monster bites caused dramatic pancreatic inflammation in bitten animals, and he was struck by an additional fact: the Gila monster eats only 3 or 4 meals a year yet maintains stable blood glucose throughout long fasts — suggesting its pancreatic biology was doing something unusual. He ordered dried Gila monster venom and ran it through Yalow's assays. [1] — Peter Attia "Exendin-4 has 53% similarity to human GLP-1: Exendin-4, a peptide in Gila monster venom discovered by John Eng, showed 53% amino acid seque…" 48:58 Working with colleague Jean-Pierre Rothman, he systematically separated the peptide components, identified two peptides, and named the new one Exendin-4. When he sequenced it, the result was remarkable: 53% amino acid similarity to human GLP-1, the gut hormone that stimulates insulin secretion after meals. More importantly, while native GLP-1 has a half-life of only about 2 minutes — degraded almost instantly by the enzyme DPP-4 — Exendin-4 is resistant to DPP-4 and has a half-life measured in hours. Eng had discovered a long-acting GLP-1 receptor agonist hiding in lizard saliva. [2] — Peter Attia "Native GLP-1 half-life: ~2 minutes: Native human GLP-1 has a bloodstream half-life of only about 2 minutes due to rapid degradation by the …" 49:50 The VA declined to patent the discovery; Eng patented it himself and licensed it, eventually to Eli Lilly and Amylin. In 2005, the FDA approved synthetic Exendin-4 as Byetta (exenatide), the first GLP-1 receptor agonist. Subsequent drugs — liraglutide, semaglutide, tirzepatide — built on the biology, reducing immunogenicity and extending duration. The class is now reshaping the treatment of type 2 diabetes, obesity, and cardiovascular disease, with ongoing trials in heart failure, kidney disease, sleep apnea, addiction, and Alzheimer's disease.
The Gila monster eats only 3 or 4 meals per year yet maintains remarkably stable blood glucose levels throughout prolonged fasting, which drew John Eng's scientific attention.
Exendin-4, a peptide in Gila monster venom discovered by John Eng, showed 53% amino acid sequence similarity to human GLP-1, explaining its potent pancreatic effects.
Native human GLP-1 has a bloodstream half-life of only about 2 minutes due to rapid degradation by the DPP-4 enzyme, making it useless as a standalone drug.
