Hyperhomocysteinemia, endoplasmic reticulum stress, and alcoholic liver injury

Figure 1 Homocysteine metabolism. Homocysteine has three main metabolic fates: to be remethylated to methionine, to en-ter the cysteine biosynthetic pathway, and to be released into the extracellular medium. CBS, cystathionine -synthase; MS, methionine synthase; THF, tetrahydrofolate; MTHFR, 5, 10-methylenetetrahydrofolate reductase; BHMT, betaine-ho-mocysteine methyltransferase; DMG, dimethylglycine; MAT, methionine adenosyltransferase; SAM, S-adenosylmethionine; SAH, S-adenosylhomocysteine.