Every time bread develops a golden crust or meat gets a delicious browned surface, the Maillard reaction occurs. It is this reaction that creates the familiar aroma and taste of freshly cooked food. But few people know that this same chemical reaction slowly proceeds inside our bodies throughout our lives.
Gradually, sugars interact with proteins and fats, forming advanced glycation end products—AGEs. These compounds accumulate in collagen and other long-lived proteins, making tissues stiffer and less elastic. Over time, they promote chronic inflammation and are linked to the development of diabetes, cardiovascular diseases, kidney damage, eye problems, and many other age-related pathologies. For a long time, it was believed that once these chemical changes occurred, they remained in the tissues forever.
It is this notion that is now beginning to be revised.
Scientists from Revel Pharmaceuticals, in collaboration with Calico Life Sciences and the University of Colorado Anschutz, have developed an enzyme capable of removing already accumulated AGE modifications of proteins. The study was published in July 2026 in the journal Nature Communications.
Aaron K. Craven, the project leader and CEO of Revel Pharmaceuticals, explained that the enzyme CMLase was developed through a combination of computational screening, artificial intelligence, and directed evolution. The initial basis came from enzymes of soil microorganisms that naturally break down organic matter. The researchers analyzed over 500 million protein variants and, after several cycles of engineering optimization, obtained an enzyme capable of effectively removing Nε-carboxymethyllysine (CML)—one of the most common and stable AGE modifications.
The special feature of CMLase is not only that it removes CML. The enzyme restores the original lysine amino acid residue, as if erasing a chemical 'tag' that appeared on the protein during the aging process.
The results were impressive. In skin samples from a 75-year-old donor, the CML content decreased to levels characteristic of much younger tissues. In artery samples, the amount of this modification decreased by more than 70%. Simultaneously, the tissues became less stiff, and their mechanical properties partially recovered. This is one of the first studies to show that age-related chemical damage to proteins, long considered irreversible, can be eliminated enzymatically.
Renowned biochemist John Baynes, who has dedicated decades to studying advanced glycation end products, called the work a "true triumph of modern methods." According to him, AGEs accumulate particularly actively in collagen—a protein that renews extremely slowly and can remain in tissues for about fifteen years. Until now, there was virtually no way to selectively remove such molecules.
The next stage will be clinical trials. The developers plan to initially test CMLase for eye diseases associated with diabetes and age-related changes in the retina and lens. If the technology proves safe and effective in patients, it could form the basis of a new class of drugs targeting not the symptoms of aging, but one of its molecular causes.
Michael Jewett, a professor of bioengineering at Stanford University, noted that the work opens up an entirely new direction in medicine. Instead of only influencing processes within cells, it becomes possible to clean the extracellular matrix—the protein scaffold that supports all body tissues and gradually changes with age.
The study does not promise an "elixir of youth" nor does it negate natural aging. However, it demonstrates a fundamentally new possibility: chemical damage to proteins, long considered irreversible for decades, can be repaired with the help of enzymes. If the results are confirmed in clinical trials, medicine will take an important step from simply slowing down age-related changes to their partial molecular restoration.
Sometimes the greatest discoveries begin with a simple observation of nature. This time, soil microorganisms, which have perfected the art of breaking down the old to make way for the new over millions of years, have provided a clue to humanity.
