L-Homocysteine

L-Homocysteine (CAS No.: 6027-13-0) is a thiol-containing, proteinogenic amino acid with L-configuration that serves as a key intermediate in mammalian methionine metabolism, arising from the demethylation of methionine and functioning as a precursor for the biosynthesis of both methionine and cysteine. As a central metabolite in one-carbon metabolism and transsulfuration pathways, L-homocysteine plays an important role in regulating cellular redox balance and methylation reactions. Elevated levels of L-homocysteine are implicated in hyperhomocysteinemia, a pathological condition associated with vascular dysfunction, cardiovascular disease, and stroke, partly through the induction of endothelial inflammation. Mechanistically, L-homocysteine has been shown to upregulate Cathepsin V expression, contributing to vascular endothelial injury and inflammatory signaling cascades, making it a relevant tool for studying oxidative stress, endothelial dysfunction, and inflammation-related pathways. In vitro, L-homocysteine is commonly used in the micromolar to millimolar concentration range to model disease-associated metabolic stress and endothelial impairment, while in vivo applications support investigations into cardiovascular and neurodegenerative disorders. Its utility in biomedical research extends to drug discovery efforts targeting metabolic regulation, redox homeostasis, and vascular inflammation, with experimental concentrations or dosing regimens varying depending on specific study designs and biological systems.