Restoring a protein called Menin in the brains of mice improved several markers of aging at once, according to a study published March 16, 2023 in the open access journal PLOS Biology. A separate treatment with the amino acid D-serine improved cognition in the animals. The work was led by Lige Leng of Xiamen University in Xiamen, China, and colleagues.
The target of the research was the hypothalamus, a small structure that helps coordinate metabolism and other basic bodily functions. It also appears to shape how the body ages more broadly. When inflammatory signaling rises in this region, the effects are not confined to the brain - tissues elsewhere in the body change too. That is the thread the researchers were pulling on, since memory decline, thinning skin, and falling bone mass are usually treated as unrelated problems of getting older.
Leng's group had previously shown that Menin acts as a brake on inflammation in the hypothalamus. The obvious follow-up question was whether losing that brake helps set age-related decline in motion. The 2023 experiments pointed toward a link between brain inflammation, metabolism, and aging across the body, suggesting a single upstream mechanism might be influencing outcomes that look separate from the outside.
This remains animal work, and the study's authors themselves connect the supplement side of the findings to a picture that later research has complicated. Subsequent studies have both added to the inflammation-aging model and shown why the D-serine results in particular need cautious interpretation rather than direct translation to people.