Is Gpld1 legal in the United Kingdom?

A liver enzyme released into blood during exercise that transferred the cognitive benefits of running to sedentary aged mice. Higher in active older people; never administered to anyone.

In 2020 a Science paper reported that plasma from exercised aged mice, transfused into sedentary aged mice, transferred the effects of exercise on adult neurogenesis and cognition. Screening the plasma identified Gpld1, a liver-derived enzyme that cleaves glycosylphosphatidylinositol anchors, as rising after exercise and correlating with improved cognitive function in aged mice.

Mechanism: In mice, Gpld1 is a liver-derived enzyme released into plasma after exercise that cleaves glycosylphosphatidylinositol anchors, releasing GPI-anchored proteins from cell surfaces. The 2026 Cell work identifies GPI-anchored tissue-nonspecific alkaline phosphatase on brain endothelium as the substrate that carries the cognitive effect: cerebrovascular levels of that enzyme rise with age, mimicking that rise impaired blood-brain transport and cognition in young mice, and inhibiting it restored youthful hippocampal transcriptional signatures and rescued cognition in old mice.

Regulatory history: Not approved and never administered to a human. No interventional trial of Gpld1 is registered for any indication. The only registered human study using it is observational.

Licenses medicines for the UK market. A compound without a marketing authorisation is an unlicensed medicine, which can only lawfully be supplied for human use through a prescriber under the specials scheme, not sold as a research product.

The classification above is the The Longevity Archive reading of Medicines and Healthcare products Regulatory Agency listings for Gpld1 at the reviewed date, not a legal opinion. Rules change, and importing, prescribing and possessing a compound can each be treated differently. Check the regulator directly before acting on anything here.