D-Methionine

D-Methionine is the D-enantiomer of methionine, a sulfur-containing essential amino acid. Unlike the naturally occurring L-form, D-methionine is not incorporated into proteins but has demonstrated significant antioxidant properties and protective effects in various preclinical and clinical settings. It acts as an inhibitor of methionine aminopeptidase 2, an enzyme involved in protein processing[1]. D-Methionine has been studied for its ability to protect against cisplatin-induced anorexia, renal injury, radiation-induced cell death and mucosal injury, as well as hearing loss caused by cisplatin, carboplatin, aminoglycosides or noise exposure[8]. Its mechanisms include antioxidant activity—scavenging free radicals—and modulation of inflammatory pathways such as inhibition of nuclear factor-kappa B (NF-κB) signaling[6][8]. While it is used in dietary supplements for liver support and detoxification[5], its pharmaceutical development status remains limited; a phase 3 trial for prevention of hearing loss was terminated without results reported[8].

Other names

(R)-methionine