💊 A simple amino acid may slow Alzheimer’s — and it’s already widely available

Researchers in Japan report that arginine, a common and inexpensive amino acid, can significantly reduce toxic protein buildup in the brain and suppress inflammation — two core drivers of Alzheimer’s disease.

🔹 Arginine inhibits the aggregation of Aβ42, the most toxic form of amyloid-beta, with stronger effects at higher concentrations.

🔹 The study used two animal models: fruit flies engineered with the Arctic Aβ42 mutation, and mice carrying three familial Alzheimer’s mutations (App NL-G-F line).

🔹 In mice, oral arginine reduced amyloid plaque levels, lowered insoluble Aβ42 in the brain, and improved performance in behavioral tests.

🔹 It also suppressed genes linked to pro-inflammatory cytokines — targeting not just protein aggregation, but neuroinflammation as well.

🔹 The work was led by Yoshitaka Nagai at Kindai University (Osaka) and published in Neurochemistry International.

🧠 Mechanistically, arginine acts as a chemical chaperone, helping proteins maintain their proper 3D structure and preventing them from clumping into toxic aggregates.

Unlike most experimental Alzheimer’s therapies, arginine is already widely used in medicine and can cross the blood–brain barrier — meaning it could potentially move to clinical testing much faster.

This doesn’t mean a cure is around the corner. But it’s a rare case where a low-cost, well-known molecule shows multi-target effects against one of the most complex brain diseases.

https://www.sciencedaily.com/releases/2026/05/260504075512.htm