The (amide-)N-methylnicotinamide is a microbe-derived NAD(+) precursor that drives gut stem cell renewal.

Systemic (amide-)N-methylnicotinamide supplementation promotes intestinal stem cell regeneration and gut epithelial repair in Drosophila and mice, linked to SIRT1-dependent NAD redox activity.

• Why it matters: NAD decline is associated with chronic and inflammatory disease, but restoring NAD in the gut and supporting epithelial renewal remains a key therapeutic gap.
• What they did: Commensal bacteria and probiotic species produce N-MNA; stool N-MNA is reduced in patients with gut dysbiosis and inflammation, and stable isotope tracing shows rapid uptake and incorporation into NAD redox reactions.
• The result: Genetic and pharmacological tests indicate N-MNA is converted to NAD+ via the Preiss-Handler pathway, and manipulating SIRT1 in Drosophila plus ISC lineage tracing in mice shows N-MNA drives regeneration.

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