Scientists Just Reversed a Hallmark of Aging
In this YouTube monologue, Nick Norwitz explains a newly published Nature Communications study that engineered an enzyme, dubbed CMLase, to erase the advanced glycation end‑product N‑carboxymethyl‑lysine (CML) from the extracellular matrix. CML accumulates as a result of sugar‑protein cross‑linking, a form of molecular “rust” that has been considered permanent and contributes to tissue stiffening and age‑related decline. Using directed evolution—a rapid, laboratory‑based evolution technique—the researchers transformed a naturally occurring protein into CMLase, which specifically removes CML residues. The enzyme was applied to human skin, eye, and arterial samples from older donors, achieving over 70% reduction of CML in aged arteries and restoring molecular signatures to resemble those of a 31‑year‑old. Norwitz emphasizes that while this does not constitute full reversal of aging, it demonstrates that a previously irreversible hallmark can be chemically reversed, opening avenues for developing similar tools to target other age‑related molecular damages. He concludes by posing the question of what future targets this technology might address.
