Muramyl dipeptide-d3 (MDP-d3) is the deuterium labeled Muramyl dipeptide. Muramyl dipeptide (MDP) is a synthetic immunoreactive peptide, consisting of N-acetyl muramic acid attached to a short amino acid chain of L-Ala-D-isoGln. Muramyl dipeptide is an inducer of bone formation through induction of Runx2. Muramyl dipeptide directly enhances osteoblast differentiation by up-regulating Runx2 gene expression through MAPK pathways. Muramyl dipeptide is a NLRP1 agonist .